Detailed Explanation of EVASIN EVOH EV4405F Resin

2026-04-13

EVASIN EVOH resin is an ethylene-vinyl alcohol copolymer, used to manufacture films, sheets, and packaging containers with high oxygen barrier properties. The EVASIN series offers various grades of composition and rheological properties suitable for various processing techniques, such as multilayer co-extrusion, casting, blow molding, sheet molding, blow molding, biaxial stretching, injection molding, and extrusion molding. The ethylene content of EVASIN EVOH resin is related to its barrier properties; lower ethylene content results in higher oxygen barrier properties, and higher barrier properties lead to higher resin hardness. EVASIN EVOH (EVOH EW-3201) has excellent gas barrier properties, blocking various odors from seasonings, spices, cosmetics, etc., making it suitable for food packaging. It also exhibits excellent oil resistance and barrier properties against oils and chemical solvents, thus finding applications in automotive fuel tanks, pesticide bottles, and underfloor heating pipes.

Characteristics:

Excellent gas barrier properties, affected by humidity

Good printability

Oil resistance

Solvent resistance

Weather resistance

High transparency

High rigidity

Excellent flexibility

Good antistatic properties

Moisture retention

Good surface gloss

EVASINT EVOH Naming Principles:

The letters E and V represent EVOH.

The third and fourth digits represent the ethylene content: for example, 32 represents 32% ethylene content; 38 represents 38% ethylene content; 44 represents 44% ethylene content.

The fifth and sixth digits are related to fat melting: 01 represents fat melting of 1-2 G/min, 51 represents a new specification with unchanged fat melting (190℃, 2160 G).

The letter V represents: no processing aids added.

The letter F represents: compounding processing aids added.

EVOH has excellent barrier properties against gases such as oxygen, nitrogen, and carbon dioxide, but due to its hydrophilic groups, it has poor barrier properties against water vapor. Therefore, when considering barrier properties against all gases, EVOH is generally used as an intermediate layer in co-extrusion molding with traditional hydrophobic thermoplastics.

EVASIN EV-4405F is mainly used in the following fields:

Packaging:

Food Packaging: It is used as an intermediate barrier layer in composite films for aseptic packaging, hot cans, and retort pouches, packaging dairy products, meat, canned juice, and condiments. It effectively prevents oxygen and moisture from entering the packaging, extending the shelf life of food and maintaining its flavor and quality. For example, in milk powder packaging, it prevents the milk powder from getting damp and oxidizing, ensuring that the nutritional components of the milk powder are not destroyed.

Non-food packaging: Used for packaging solvents, chemicals, air conditioning structural components, gasoline drum liners, electronic components, etc. Due to its excellent barrier properties, it can prevent solvent evaporation, chemical leakage, and protect electronic components from external environmental influences.

Automotive industry:

Due to its good oil resistance and barrier properties, it can be used as a barrier layer material for automobile fuel tanks, effectively preventing fuel evaporation and leakage, reducing environmental pollution, and improving vehicle safety and fuel efficiency.

Other fields:

It can be used to produce packaging materials for household goods, underfloor heating pipes, wallpaper, etc. In household goods packaging, it provides good protection and barrier properties; in underfloor heating pipes, it helps improve the pipes' corrosion resistance and oxygen barrier properties, extending the pipes' service life; in wallpaper, it can enhance the wallpaper's performance, such as waterproofing, moisture resistance, and odor blocking.

Website: www.elephchem.com

whatsapp: (+)86 13851435272

E-mail: admin@elephchem.com

#EVOH EW-3201 #EVASIN EV-4405F #ethylene-vinyl alcohol copolymer

Which is better, PVC or EVA?

2026-04-13

PVC and Ethylene Vinyl Acetate (EVA) are two widely used polymer materials with different performance characteristics and application areas. This article will comprehensively analyze the performance characteristics of PVC and EVA from multiple perspectives to discuss which material is better.

1. Performance Characteristics of PVC

PVC, or polyvinyl chloride, is a polymer compound with excellent electrical properties, mechanical properties, chemical stability, and abrasion resistance.

Main advantages include:

Good Electrical Insulation: PVC has good electrical insulation properties, with low dielectric constant and dielectric loss, and also high arc resistance. These excellent electrical properties make PVC widely used in the electronics field, such as in the manufacture of wires and cables, and capacitor casings.

Excellent Mechanical Properties: PVC has high tensile strength, flexural strength, and impact strength, as well as good abrasion resistance and weather resistance. These excellent mechanical properties make PVC widely used in various fields, such as in the manufacture of pipes, doors and windows, and flooring.

Good Chemical Stability: PVC has good resistance to most organic solvents and acids and alkalis. This chemical stability makes PVC widely used in the chemical field, such as in the manufacture of laboratory equipment and chemical piping.

Good abrasion resistance: PVC products have high surface hardness, thus exhibiting good abrasion resistance. This allows PVC products to be used for extended periods in harsh environments, such as factories and mines.

However, the environmental friendliness of PVC products has been controversial. This is because the production and use of PVC generate some harmful substances, such as dioxins and vinyl chloride monomer. These substances pose potential hazards to human health and the environment.

2. Performance Characteristics of EVA

EVA, or ethylene-vinyl acetate copolymer, is a polymer material with excellent flexibility, abrasion resistance, water resistance, and antibacterial properties.

Main advantages include:

Good flexibility: EVA (such as EVA 5110J) has excellent flexibility, allowing it to be bent without easily breaking. This makes EVA widely used in applications requiring frequent bending, such as in the manufacture of athletic shoe soles and sealing strips.

Good abrasion resistance: EVA (such as EVA V6110S) products have moderate surface hardness, thus exhibiting good abrasion resistance. This allows EVA products to be used for extended periods in harsh environments, such as factories and mines.

Good Water Resistance: EVA possesses excellent water resistance, effectively preventing moisture penetration. This makes EVA widely used in applications requiring waterproofing, such as raincoats and waterproof shoes.

Good Antibacterial Properties: EVA has certain antibacterial properties, effectively inhibiting bacterial growth and reproduction. This makes EVA widely used in applications requiring antibacterial properties, such as medical devices and food packaging.

However, EVA has poor high-temperature resistance, easily deforming and decomposing at high temperatures. This limits its application in some high-temperature fields.

3. Application Areas of PVC and EVA

Because PVC and EVA have different performance characteristics, their application areas also differ. PVC is mainly used to make wires and cables, pipes, doors and windows, flooring, etc., while EVA is mainly used to make sports shoe soles, sealing strips, raincoats, waterproof shoes, etc. In applications requiring multiple properties, such as medical devices and food packaging, PVC and EVA are sometimes blended or compounded to improve product performance.

In conclusion, PVC and EVA each have their advantages and disadvantages, and which material is better depends on the specific application and requirements. When choosing between PVC and EVA, it is necessary to comprehensively consider factors such as product performance and environmental friendliness to select the most suitable material to meet the application requirements.

Website: www.elephchem.com

whatsapp: (+)86 13851435272

E-mail: admin@elephchem.com

#Ethylene Vinyl Acetate #EVA V6110S #EVA 5110J

Ethyleneamines The Versatile Building Blocks of Modern Industry

2026-03-11

#Cosmetics chemical industry

In the world of fine chemicals, few product families offer the versatility of Ethyleneamines. These reactive compounds are the unsung heroes behind many high-performance materials we use daily. From the durable coating on a wind turbine blade to the additives keeping a car engine clean, Ethyleneamines act as essential "linkers" and modifiers.

For industrial purchasers and R&D engineers, understanding the specific applications of each homolog—such as EDA, DETA, TETA, and Piperazine—is key to optimizing production efficiency.

1. The Backbone of Epoxy Curing Agents

The most significant application for Ethyleneamines lies in the coatings and adhesives industry. Ethylenediamine (EDA), Diethylenetriamine (DETA), and Triethylenetetramine (TETA) are the primary raw materials for manufacturing epoxy curing agents.

Through cross-linking reactions, they transform liquid epoxy resins into tough, solid plastics. This process is crucial for creating:

Heavy-duty anti-corrosion paints for marine and industrial use.
Floor coatings that withstand heavy forklift traffic.
Composite materials used in aerospace and automotive parts.

2. Enhancing Agrochemical Formulations

Modern agriculture relies on Ethyleneamines for stability and efficacy. They are widely used to synthesize fungicides and insecticides. Furthermore, Ethyleneamines are the precursors to chelating agents (like EDTA). In pesticide formulations, these chelating agents effectively manage water hardness, ensuring that the active ingredients remain stable and effective regardless of local water quality.

3. High-Performance Lube Oil and Fuel Additives

To keep engines running smoothly, manufacturers use "ashless dispersants" derived from Polyethylene Polyamines. These additives prevent the formation of sludge and varnish deposits on engine parts. Additionally, Piperazine and its derivatives play a vital role in fluid modification, ensuring lubricants perform under extreme temperatures.

4. Paper, Pharma, and Beyond

The versatility continues. In the paper industry, DETA is used to produce wet-strength resins (PAE), ensuring tissues and packaging maintain their integrity when wet. In the pharmaceutical sector, Piperazine is a critical intermediate for synthesizing various active pharmaceutical ingredients (APIs).

Partner with a Specialist

Whether you are formulating a new epoxy hardener or a fuel additive package, the quality of your raw materials matters. At Nanjing Bewell Chemical, we go beyond standard supply. bewellchem offers customization and modification services, ensuring our Ethyleneamines meet the precise purity and viscosity requirements of your unique application.

How to distinguish between coupling agents, crosslinking agents, and dispersants

2025-10-29

In the fields of material processing and chemical production, coupling agents, crosslinking agents, and dispersants are three commonly used additives with different functions, but they all have a critical impact on material properties. The following provides a detailed explanation from the aspects of definition, main characteristics, typical types, and core differences.

Coupling agent
Coupling agents are a type of chemical substance that can act as a "bridge" at the interface between two materials with different properties, like a "diplomat" connecting the inorganic and organic worlds. Their core function is to improve the interfacial bonding between inorganic and organic materials, thereby enhancing the comprehensive performance of composite materials.
Parent structure: Molecules usually contain two different functional groups with one end being a hydrophilic inorganic group (such as silicon oxygen bond, titanium oxygen bond, etc.), which can undergo chemical reactions or physical adsorption with hydroxyl and carboxyl groups on the surface of inorganic materials (such as glass, ceramics, metals, fillers, etc.); The other end is a hydrophilic organic group (such as amino, epoxy, vinyl, etc.), which can undergo chemical reactions or be physically compatible with organic materials (such as plastics, rubber, resins, etc.).
Enhanced interface bonding: By forming chemical bonds or strong physical interactions at the interface, the interface "gap" caused by polarity differences between inorganic and organic materials is eliminated, interface defects are reduced, and stress can be effectively transmitted at the interface.
Improving material performance: It can significantly enhance the mechanical properties of composite materials, such as tensile strength, impact strength, bending strength, etc; At the same time, it can improve the water resistance, corrosion resistance, heat resistance, and processing flowability of the material.

Low dosage but significant effect: usually only 0.1% -5% (relative to the amount of inorganic filler) needs to be added in composite materials to significantly improve interfacial performance.

Silane coupling agent: such as KH550 (γ - aminopropyltriethoxysilane), commonly used in glass fiber reinforced plastics, coatings, adhesives. The inorganic end is siloxane, which can react with hydroxyl groups on the surface of inorganic materials. The organic end amino group can react with epoxy resins, polyurethanes, etc.

Titanium ester coupling agent: such as isopropyl tristearoyl titanium ester, suitable for the composite of fillers such as calcium carbonate and talc powder with polyolefins, can reduce the viscosity of the system and increase the filling amount.

Crosslinking agent
Crosslinking agent is a substance that can connect linear polymer chains through chemical bonds to form a three-dimensional network structure, like an "architect" that builds material strength. Its function is to change the molecular structure of polymer materials, thereby optimizing their physical and chemical properties.
Multi functional group structure: The molecule contains at least two reactive functional groups (such as double bonds, epoxy groups, isocyanate groups, peroxide groups, etc.) that can react chemically with active functional groups (such as hydroxyl groups, amino groups, double bonds, etc.) on the polymer chain.
Change molecular morphology: Convert linear or branched polymers into a network structure, transforming the material from thermoplastic to thermosetting (some with lower cross-linking still remain thermoplastic, but their properties have changed).
Optimize material properties: significantly improve the material's heat resistance (such as increasing glass transition temperature), solvent resistance (insoluble in solvents), mechanical strength (such as increasing hardness and elastic modulus), while reducing the material's creep and shrinkage rate.
Specific reaction conditions: Different crosslinking agents need to initiate crosslinking reactions under specific conditions (such as temperature, pressure, light, catalyst, etc.). For example, peroxide crosslinking agents need to be heated and decomposed to produce free radicals, while sulfur crosslinking needs to be carried out in the presence of a promoter.

Sulfur and sulfur-containing compounds: mainly used for rubber cross-linking (vulcanization), connecting rubber molecular chains through the formation of sulfur bridges, endowing rubber with elasticity and wear resistance.
Peroxides, such as diisopropylbenzene peroxide (DCP), are suitable for crosslinking polyethylene, ethylene propylene rubber, etc. They crosslink polymer chains through free radicals generated by decomposition.

Isocyanates, such as toluene diisocyanate (TDI), are commonly used for crosslinking polyurethane. They react with hydroxyl groups to form urea bonds, curing polyurethane from a prepolymer to an elastomer or rigid foam.

Dispersant
Dispersant is a chemical substance that can promote the uniform dispersion of solid particles in liquid media and prevent their re aggregation. It is equivalent to a "moderator" who reconciles particles and fights, and its core function is to maintain the stability of the dispersion system.
Surface activity: The molecule contains hydrophilic groups (compatible with the dispersion medium) and hydrophilic groups (adsorbed on the surface of solid particles), which can reduce the interfacial tension between solid particles and the dispersion medium.
Stable dispersion system: Dispersion stability is achieved through two mechanisms: one is the adsorption of hydrophilic groups on the surface of particles, and the extension of hydrophilic groups towards the dispersion medium to form a charge layer (ionic dispersant), which uses charge repulsion to prevent particle aggregation; The second is the formation of a steric hindrance layer (non-ionic dispersant) by hydrophilic groups, which hinders particles from approaching each other.
Improving processing performance: It can reduce the viscosity of the dispersed system, improve fluidity, and facilitate processing operations such as stirring, conveying, and coating; At the same time, it makes the particle distribution more uniform and avoids performance defects caused by excessive local concentration.
Widely applicable: It can be used for dispersing pigments, fillers, nanoparticles, etc. in media such as water, organic solvents, resins, etc., such as coatings, inks, ceramic slurries, cosmetics, and other fields.

Ionic dispersants, such as sodium dodecyl sulfate (anionic), are commonly used for dispersing pigments in aqueous systems by generating negative charges that cause particles to repel each other.
Non ionic dispersants: such as polyoxyethylene ethers, suitable for non-aqueous systems or ion sensitive systems, stable dispersion through steric hindrance.
Polymer dispersants, such as polycarboxylate esters, have high molecular weight, strong adsorption capacity, significant steric hindrance effect, and are suitable for dispersing high concentrations and fine particles.

SAT NANO is a best suppleir of nano powder and dispersion in China, we can offer different kind of dispersion, we disperse well the nanopartilce with dispersant, if you have any enquiry of dispersion, please feel free to contact us at admin@satnano.com

#antimony oxide dispersion #titanium ester coupling agent #nano ATO antimony oxide dispersion

Other factors affecting the resistance of silver paste besides the shape of silver powder

2025-10-29

Silver paste

resistance is influenced by multiple factors, and in addition to the shape of silver powder, the following key factors also significantly affect its conductivity:

1、 Characteristics of silver powder itself

The particle size and distribution of silver powder directly affect the resistance. When the particle size of silver powder decreases from 5 μ m to 1 μ m, the specific surface area increases, the number of indirect contacts between particles increases, and the resistance can be reduced by 30% -40%. However, if the particle size is too small (<0.5 μ m), it is prone to agglomeration, which in turn leads to an increase in resistance. The purity of silver powder is also crucial. If it contains impurities such as copper and iron exceeding 0.1%, it will form electron scattering centers, increasing the resistance by more than 15%.

2、 Composition ratio of silver paste

Silver content is the core factor. When the proportion of silver powder increases from 70% to 90%, the conductive path becomes denser and the resistance can decrease by 50% -60%. However, excessive silver content will reduce the fluidity of the slurry. The proportion of glass powder needs to be precisely controlled. If it exceeds 5%, an insulation barrier layer will form, leading to a sudden increase in resistance; If it is less than 2%, it cannot guarantee good bonding between silver powder and substrate, and the contact resistance increases.

3、 Preparation and sintering process

The sintering temperature and time have a significant impact. In the range of 500-600 ℃, for every 50 ℃ increase in temperature, the silver particles fuse more fully, and the resistance can be reduced by 10% -15%. However, exceeding 650 ℃ may cause oxidation of the silver layer or damage to the substrate. The dispersion process determines the uniformity of silver powder. When the ultrasonic dispersion power is insufficient, the silver powder agglomeration rate exceeds 20%, and the local resistance will fluctuate by 2-3 times.

4、 Application environment and aging

An increase in temperature will cause a linear increase in the resistance of silver paste. Within the range of -40 ℃ to 85 ℃, the resistance increases by 2% -3% for every 10 ℃ increase in temperature. When the humidity exceeds 60%, the migration of silver ions accelerates, and the resistance can increase by 10% -20% after long-term use. Mechanical stress such as bending and vibration can damage the conductive network, causing a sudden increase in resistance, with an amplitude of up to 5% -15%.

SAT NANO is a best supplier of silver powder in China, we can offer nano particle and micron particle, if you have any enquiry, please feel free to contact us at admin@satnano.com

#silver paste #silver powder #silver powder for paste

Polyvinyl Alcohol (PVA) Fully Hydrolyzed 99 Series

2025-10-27

Polyvinyl alcohol (PVA) is one of the most important and widely used water-soluble polymers in industrial applications. Its preparation process involves first polymerizing vinyl acetate (VAc) to form polyvinyl acetate (PVAc). The vinyl acetate groups (-OAc) on the PVAc are then converted to hydroxyl groups (-OH) through an alcoholysis (hydrolysis) reaction. Based on the degree of alcoholysis, PVA is divided into two major series: fully hydrolyzed and partially hydrolyzed.

PVA

Fully hydrolyzed 99 series PVA (such as ElephChem pva 2699, 2499, 2099, and 1799) refers to grades with a degree of hydrolysis of 99.0 mol% or higher. This extremely high degree of hydrolysis is the core prerequisite for these PVA grades to achieve high performance, strength, and water resistance. This blog will analyze, from four perspectives: molecular structure, grade differentiation, performance advantages, and key application areas, how fully hydrolyzed 99 Series PVA has become the cornerstone of "hardcore" materials such as high-performance fibers, specialty films, and durable adhesives.

1.Molecular Structure Determine Performance: The Mechanism and Effect of Complete Hydrolysis

1.1 Hydroxyl Density and Hydrogen Bonding Network Construction

In the fully hydrolyzed 99 Series, nearly all hydrophobic vinyl acetate groups on the molecular chain are replaced by hydrophilic hydroxyl groups. Hydroxyl groups (-OH) are extremely polar functional groups that form strong intramolecular and intermolecular hydrogen bonds, building a highly dense and stable three-dimensional network.

This dense hydrogen-bonding network contributes to two crucial molecular effects:

High crystallinity: Strong hydrogen bonding forces enable PVA molecular chains to stack neatly and tightly, forming highly ordered crystalline regions. This increased crystallinity is the fundamental reason for the high tensile strength and high modulus of 99 Series PVA.
Water Resistance: The dense hydrogen bond network makes it difficult for external water molecules to penetrate the crystals at room temperature and disrupt the connections between the molecular chains, effectively preventing PVA from dissolving. Therefore, 99 series PVA is essentially insoluble in water at room temperature and typically requires hot water above 90°C to fully dissolve and disperse. This ensures its structural stability in humid environments and aqueous systems.

1.2 Linear Correlation between Degree of Polymerization and Viscosity/Strength

Assuming a constant degree of hydrolysis (HD>99.0%), the differences between fully hydrolyzed 99 series PVA grades are primarily determined by the average degree of polymerization (DP) or average molecular weight (MW). DP is a key parameter that determines the rheological properties of polymer solutions and the mechanical properties of the final product.

The DP ladder of ElephChem 99 series grades (based on the average DP):

Ultra-High DP (Polyvinyl Alcohol 2699): DP = 2600-3000. These grades have the longest molecular chains and the highest degree of chain entanglement. Its highest solution viscosity imparts exceptional cohesive strength and adhesion to the cured material, making it an ideal choice for manufacturing high-strength, high-modulus fibers and specialty high-viscosity adhesives.
Medium-high degree of polymerization (Polyvinyl Alcohol 2499 / Polyvinyl Alcohol 2099): DP = 2,000-2,500. This grade offers a balanced viscosity and mechanical properties. It is the most widely used grade for sizing agents in the textile industry and for general-purpose, high-performance coatings and films.
Medium-low degree of polymerization (Polyvinyl Alcohol 1799): DP = 1,700-1,800. Its relatively low solution viscosity facilitates its use in systems with high solids content or requiring rapid penetration. For example, precursors for polyvinyl butyral (PVB) require precise molecular weight control (e.g., 1799 for PVB, MW = 76,000-82,000) to ensure efficient acetalization and the quality of the resulting interlayer film.

2. Core Performance Advantages of the Fully Hydrolyzed PVA 99 Series

Excellent Mechanical Properties (High Strength, High Modulus): High crystallinity gives PVA high tensile strength and modulus. Wet or dry-wet spinning yields high-strength, high-modulus PVA fibers with properties comparable to those of ultra-high-density polyethylene (UHMWPE). These fibers are a key raw material for replacing asbestos in cement reinforcement and ballistic materials.
Excellent Gas Barrier Properties: PVA films, particularly those produced from the 99 series, offer one of the best barrier properties against gases like oxygen and nitrogen among known polymer materials. The highly hydrogen-bonded network within their molecular structure prevents gas permeation, making them ideal as high-performance barrier layers for oxygen-sensitive food and pharmaceutical packaging.
Chemical and Oil Resistance: The 99 series PVA shows good resistance to solvents, oils, greases, and weak acids and bases because its molecules are very stable and it has few non-crystalline areas. This makes it useful for industrial coatings and special glues.
Thermal stability: High crystallinity gives 99 series PVA a higher glass transition temperature (Tg) and melting temperature (Tm), improving the material's resistance to heat deformation and upper temperature limit.

3. Analysis of Key Industrial Applications of Fully Hydrolyzed 99 Series PVA

The unique properties of 99 Series PVA make it irreplaceable in multiple high-value-added sectors:

3.1 High-Strength High-Modulus PVA Fiber (HTHM PVA Fiber)

This is one of the most valuable end-products of 99 Series PVA. For example, the 1799 grade, with a DP of approximately 1750, achieves a high degree of molecular orientation through specialized spinning, heat treatment, and stretching processes.

Applications: Used to replace asbestos and steel mesh in construction, it reinforces cement, mortar, and concrete, significantly improving the material's impact resistance, freeze-thaw resistance, and fatigue resistance. It is widely used in civil engineering structures such as highways, water conservancy projects, tunnel linings, and cement slabs.

3.2 Textile and Paper Industry

Textile Warp Sizing: High-polymerization grades such as 2499 and 2699 provide an extremely tough and smooth size film, significantly improving the abrasion resistance and breaking strength of warp yarns during weaving. They are the preferred size for high-density, high-count fabrics (such as denim and premium cotton).
Papermaking Surface Sizing Agent: As a surface sizing agent, the 99 series PVA forms a high-strength film on the surface of paper, significantly improving its surface strength, folding resistance, and printability. This is crucial for high-end coated paper and specialty functional papers (such as thermal paper and dust-free paper).

3.3 Polyvinyl Butyral (PVB) Precursor

PVB is a core material for automotive safety glass and architectural laminated glass. As an intermediate in the acetalization reaction, the quality of PVA directly determines the optical clarity, toughness, adhesion, and aging resistance of the final PVB film. Grades: 1799 specialty grades (such as SX-I/II/III) with a DP ≈ 1700-1850 are precisely designed to ensure ideal molecular structure and uniform dispersion during the subsequent acetalization reaction, meeting the stringent optical quality requirements of safety glass.

3.4 High-Performance Building Adhesives and Dry-Mix Mortars

In the construction industry, 99-series PVAs are used as high-performance additives to improve material durability and adhesion.

Applications: As secondary dispersing binders and water-retaining agents in mortars and putty powders, their high bond strength and water resistance ensure the stability and durability of wall putties, tile adhesives, and other materials in humid and temperature-stable environments.

4. Conclusion: Future Outlook for Fully Hydrolyzed 99-Series PVA

99-series PVAs are a classic and promising branch of polymer materials science. By precisely controlling the degree of hydrolysis and polymerization, as demonstrated by ElephChem's grade system, the industry can develop specialized grades tailored to meet the demands of diverse and demanding applications.

From high-strength fibers that reinforce modern infrastructure, to PVB interlayer films that ensure safety, to environmentally friendly, high-performance coatings that enhance quality of life, the 99 series PVA, with its unparalleled strength, stability, and water resistance, continues to play a key role as a driver of high-performance, "hardcore" materials in the upgrading and sustainable development of the global manufacturing industry. As novel uses, like 3D printing and medical hydrogels, ask for better PVA, studies into improving and changing the 99 series PVA will likely increase. This will probably expand its value in industry and its market potential.

Website: www.elephchem.com

Whatsapp: (+)86 13851435272

E-mail: admin@elephchem.com

#Polyvinyl Alcohol 2499 #PVA 1799 #CCP BF 17 #GOHSENOL NH-18 #Carboxylated PVA #shuangxin pva #Polyvinyl Alcohol 2099 #Mowiol 28-99

Polyvinyl Alcohol (PVA) Partially Hydrolyzed 88 Series

2025-10-27

The core of polyvinyl alcohol (PVA) performance lies in its degree of hydrolysis. The 88 Series PVA, which is partially hydrolyzed (usually around 87.0 to 89.0 mol%), differs from the fully hydrolyzed 99 Series in that it provides better flexibility, interfacial activity, and water solubility that can be adjusted.

When PVA is partially hydrolyzed, about 11% to 13% of vinyl acetate groups (-OAc) are kept in the molecular chain. Because of these hydrophobic groups, the 88 Series PVA acts as an amphiphilic substance with high interfacial activity, unlike the 99 Series. Because of this, it works well as a protective colloid in emulsion polymerization and as a flexible base for strong adhesives and coatings with specific functions.

1. Molecular Structure Determines Function: Amphiphilicity and Protective Colloid Mechanism

1.1 Amphiphilicity Due to Hydrophobic-Hydrophilic Balance

Partially hydrolyzed 88 series PVA molecular chains possess two functional groups with vastly different polarities:

Hydrophilic groups: A large number of hydroxyl groups (-OH).
Hydrophobic groups: A small number of evenly distributed vinyl acetate groups (-OAc).

This structure makes PVA a highly effective high-molecular-weight surfactant or protective colloid. When dissolved in water, the molecular chains adsorb at the water-oil (monomer) interface, with the hydrophobic groups tending to embed into the oil phase, while the hydrophilic groups extend toward the water phase. This unique arrangement forms a stable, high-molecular-weight physical barrier (i.e., a protective steric barrier) around the oil phase particles, effectively preventing aggregation of emulsion particles during polymerization, storage, or mechanical shear, and is the core mechanism for ensuring emulsion stability.

1.2 Reduced Crystallinity and Improved Water Solubility

Unlike the highly regular structure of the 99 series, the irregular distribution of vinyl acetate groups on the molecular chain disrupts the regular packing of PVA molecules, resulting in:

Reduced crystallinity: The proportion of crystalline regions decreases, weakening the hydrogen bond network.
Improved cold-water solubility: Lower crystallinity allows water molecules to more easily penetrate and disrupt the amorphous region structure. Therefore, 88 series PVA can dissolve quickly or even completely at lower temperatures (typically 40°C to 60°C), greatly simplifying dissolution operations during formulation and production.

2. Effect of Degree of Polymerization on Rheological Properties and Stability

Given a consistent level of partial hydrolysis, the key differences between different PVA grades are mainly in their average degree of polymerization (DP) or molecular weight (MW). The DP has a direct impact on the viscosity of the PVA solution, the thickness of the steric barrier layer, and how the emulsion ultimately performs.

The refined positioning of ElephChem's 88 series grades:

ElephChem PVA	Average degree of polymerization	Average molecular weight	Core application positioning
2688 / 2488	2400~2650	118000~130000	High molecular weight: Provides the strongest steric protection and is used in emulsion polymerizations requiring the highest stability (such as high-performance VAE emulsions).
2088 / 1788	1700~2100	84000~104000	General purpose: Balances viscosity and protection for general-purpose PVAc and VAE emulsions and adhesives.
1792	1700~1800	54000~60000	Medium-low molecular weight: Suitable for specialty water-soluble fibers and viscosity-sensitive coating systems.
0588 / 0488	420~650	21000~32000	Ultra-low molecular weight: Minimal effect on solution viscosity, suitable for inks, inkjet coatings, or as a co-stabilizer in emulsions.

High degree of polymerization (Polyvinyl Alcohol 2688 / Polyvinyl Alcohol 2488): Long molecular chains provide a stronger steric hindrance. In emulsion polymerization, long chains help distribute and stabilize monomer droplets and polymer particles, which is needed for high-solids, high-viscosity emulsions.
Ultra-low degree of polymerization (Polyvinyl Alcohol 0488 / Polyvinyl Alcohol 0588): These stabilizers function similarly to small-molecule emulsifiers, but provide improved polymer adhesion. Their low viscosity allows them to be used in high-solids coatings and slurry systems without affecting the rheological properties of the final product.

3. Analysis of Key Industrial Applications of Partially Hydrolyzed 88 Series PVA

The interfacial activity and controllable water solubility of the 88 series PVAs give them core competitiveness in the fine chemicals, adhesives, and specialty materials sectors:

3.1 Emulsion Polymerization Industry: Stabilizers and Protective Colloids

This is the core and irreplaceable application of the 88 series PVAs. It is widely used in the polymerization of monomers such as vinyl acetate (VAc), acrylates, and styrene-acrylates, and is a key additive in the manufacture of PVAc, VAE, and acrylate emulsions.

Mechanism: 88 Series PVA acts as a protective colloid, not only stabilizing the emulsion during the initial polymerization phase but, more importantly, determining the freeze-thaw resistance, mechanical shear stability, and rewettability of the final emulsion.
Applications: Architectural coating emulsions (such as interior wall latex paint), wood adhesives (white latex), textile nonwoven adhesives, carpet adhesives, etc.

3.2 Water-Solubility and Functional Films/Fibers

The low crystallinity of partially hydrolyzed PVA makes it easier to dissolve quickly in cold water, making it a preferred environmentally friendly packaging material.

Water-Soluble Packaging Film: Used for quantitative packaging of products such as pesticides, dyes, detergents, and laundry detergent beads. Upon application of water, the film quickly dissolves, releasing the contents, providing both convenience and environmental friendliness.
Water-Soluble Fiber: Used in the textile industry as temporary support yarn or "sacrificial" yarn. After the fabric is finished, the PVA fibers dissolve in warm water, leaving behind a fabric with a special openwork or structural effect.

3.3 Adhesive and Coating Systems

Adhesives: Due to the retention of hydrophobic groups in the molecular chain, 88-series PVA has better affinity and adhesion to certain hydrophobic surfaces and organic materials than 99-series PVA. It is widely used in specialty paper adhesives and rewettable adhesives (such as postage stamp adhesives).
Specialty Coatings: Ultra-low molecular weight grades (such as 0488) can be used as ink-receiving coating additives for inkjet printing paper, providing excellent pigment binding and fast drying properties without significantly increasing coating viscosity.

3.4 Other Fine Chemical Applications

Suspension Polymerization Dispersant: Used in the suspension polymerization of PVC resins, it helps control the size, porosity, and density of PVC particles, which is crucial to the processing properties of PVC resins.
Ceramic Binder: Used as a temporary binder for bonding ceramics before molding and sintering. After sintering, it can be completely burned and vaporized, leaving no residue.

4. Conclusion: Continuous Innovation in Partially Hydrolyzed 88 Series PVA

ElephChem partially hydrolyzed 88 Series PVA takes full advantage of both hydrophilic and hydrophobic elements in its molecular structure. This allows for careful control during emulsion polymerization and affects how well it sticks and dissolves in water. If the 99 Series is the "rebar" of structural materials, then the 88 Series is the "stabilizer" and "flexibility controller" of fine chemical systems. Partially hydrolyzed 88 Series PVA is still critical to the growth of modern fine chemicals and sustainable materials. This is due to the continued expansion of markets, like those for green water-based coatings, good emulsions, and biodegradable packaging, along with PVA's special interfacial chemistry and grade system.

Website: www.elephchem.com

Whatsapp: (+)86 13851435272

E-mail: admin@elephchem.com

#KURARAY POVAL #Polyvinyl Alcohol 0488 #Mowiol 4-88 #Polyvinyl Alcohol 2688 #Mowiol 56-88 #shuangxin pva #CCP BP-05S #CCP BP-24S #Polyvinyl Alcohol 2099 #PVA NH 20

High-Performance Thermally Conductive and Electrically Insulating Ceramic Fillers for Thermal Interface Materials

2025-10-23

As electronic equipment continues to evolve towards miniaturization, high integration, and increased power density, the service life of these devices is receiving growing attention. When the heat generated by electronic components during operation cannot be dissipated promptly, it leads to localized heat accumulation within the components, severely impacting the normal functioning of the electronic equipment. Particularly for high-power electrical devices, lifespan degradation primarily stems from interfacial heat dissipation issues in electronic components. Therefore, Thermal Interface Materials (TIMs) possessing both high thermal conductivity and excellent electrical insulation are crucial for ensuring their efficient operation.

electronic heat-sink

Polymer materials are commonly used as thermal interface materials in electronic components. However, the thermal conductivity of most polymer materials is below 0.5 W·m⁻¹·K⁻¹, which significantly hampers the heat dissipation efficiency of the devices. A prevalent method to enhance the thermal conductivity of polymer materials involves incorporating fillers with higher intrinsic thermal conductivity into the polymer matrix. Ceramic fillers are currently the most widely used thermally conductive fillers in thermally conductive and electrically insulating polymer composites. Commonly used inorganic thermally conductive fillers mainly include：

Oxides: Al₂O₃, ZnO, MgO, SiO₂, BeO

Nitrides: AlN, BN, Si₃N₄

Carbides: SiC

Incorporating these inorganic ceramic fillers into a rubber matrix enables the production of thermally conductive and electrically insulating materials with good overall performance. These materials show broad application prospects in fields such as electronic packaging, thermal management, energy storage, cables, and heat sinks.

AlN filler SEM

About Xiamen Juci Technology Co., Ltd.

Xiamen Juci Technology Co., Ltd. is dedicated to the R&D, production, and sales of high-performance Aluminum Nitride (AlN) ceramic fillers. We offer a comprehensive range of particle sizes, from 1 to 120 microns, to meet diverse application needs. Our AlN fillers are characterized by excellent thermal conductivity and high sphericity, ensuring superior performance in thermal management solutions. It is your ideal partner for high-performance, insulating thermal interface materials.

Contact us:
Xiamen Juci Technology Co., Ltd.

Phone: +86 592 7080230
Email: miki_huang@chinajuci.com

Website: www.jucialnglobal.com

#Aluminum Nitride (AlN) ceramic fillers #Ceramic Fillers for Thermal Interface Materials #fillers in polymer composites

A Detailed Explanation of PVA Particle Fineness Selection and Application of Different Mesh Sizes

2025-10-17

Polyvinyl alcohol (PVA), an indispensable water-soluble polymer material, is used in a wide range of fields, including construction, textiles, papermaking, and chemicals. Among the many PVA specifications, mesh size, or particle fineness, is a key factor in determining processing efficiency and final product quality.

1. Mesh Size Basics: A Measurement of Particle Size

Mesh size is a unit of measurement for powder particle fineness. It refers to the number of holes in a sieve per inch. The smaller the mesh size, the larger (coarser) the particles.

Mesh size and dissolution rate: The dissolution process of a powder begins with the wetting and penetration of the particle surface by water molecules. The finer the particle size (the larger the mesh size), the greater its specific surface area. A larger specific surface area means that water molecules can contact more PVA molecular chains, significantly accelerating wetting, swelling, and disentanglement, ultimately increasing dissolution rate.
Mesh size and dispersion uniformity: Fine particles are more easily dispersed in liquid or solid mixtures. When coarse particles (such as 20 mesh) are added to water, they are more likely to settle or clump due to density differences, forming "fish eyes" that are difficult to dissolve.
Mesh Size and Dust Density: The finer the particle size, the lower the critical velocity at which it becomes suspended in air, resulting in higher dust levels. 20 mesh PVA produces low dust, while 200 mesh PVA requires strict dust control measures.

2. Introduction and Application of PVA Specifications of Different Mesh Sizes

Mesh Size	20 mesh(Polyvinyl Alcohol 0588)	120 mesh (PVA 088-05S)	200 mesh (POVAL 22-88 S2)
Photo
Bulk Density	Relatively high	Medium	Relatively low (fluffy powder)
Key Features	The largest particles have the lowest surface area. This dissolution process is the slowest, but dust generation during operation is minimal; it is also known as a "low-dust" or "dust-free" grade.	This medium-sized particle size is the most commonly used grade in industry. It strikes a good balance between dissolution efficiency, ease of operation, and cost.	The extremely fine particles and maximum surface area ensure the fastest dissolution and the best dispersibility.
Applications	Dry-mix mortar for construction: Coarse-grained PVA, as a binder, is less likely to form high-viscosity clumps during initial mixing, allowing for better dispersion in other components (such as cement and sand). It also produces minimal dust, improving the on-site construction environment. Specialized slow-release adhesives: In certain specialized construction mortars or adhesives, PVA needs to dissolve slowly to provide lasting adhesion. Preventing rapid thickening: Suitable for formulations that require prolonged mixing and where rapid thickening of the solution is undesirable.	Conventional adhesives: Used in the manufacture of common water-based adhesives such as wood glue and paper glue. Textile sizing agents: Prepare sizings at standard temperatures and times to meet the sizing requirements of most textiles. Emulsion polymerization protective colloids: Serves as stabilizers and protective colloids in the polymerization of emulsions (such as VAE and acrylic emulsions). They provide a sufficiently rapid dissolution rate without excessively increasing system viscosity, ensuring stability and particle size distribution during emulsion polymerization.	High-end water-based coatings: Suitable for high-end paints and putty powders that require extremely high dispersibility and a minimum of residual particles. Fast Preparation/Low-Temperature Dissolution: Fine powder ensures rapid and thorough dissolution of PVA at low temperatures or under limited stirring capacity. Water-Soluble Film: Used in the production of water-soluble packaging films requiring high transparency and good solubility, such as laundry bags and pesticide packaging. Pharmaceutical/Cosmetic Excipients: Used in certain fine chemical applications requiring high precision.

3. How to Make the Best Choice?

Choosing the right mesh size for PVA is essentially a trade-off between production efficiency, environmental safety, and product performance:

For those seeking dissolution speed and product fineness (e.g., coatings and films): 200 mesh is preferred.

For those seeking versatility, balanced performance, and moderate cost (e.g., conventional adhesives): 120 mesh is preferred(PVA 088-50S).

For those emphasizing operational safety, low dust generation (e.g., large-volume batching), or specific sustained-release requirements: 20 mesh is preferred(Poval 217).

Website: www.elephchem.com

Whatsapp: (+)86 13851435272

E-mail: admin@elephchem.com

#Polyvinyl Alcohol 0588 #Mowiol 5-88 #Polyvinyl alcohol (PVA) #PVA 205S #PVA 088-05S #CCP BP-05S #CCP BP-24S #POVAL 22-88 S2 #sinopec NJ-I #Sundy NJ-I

A Guide to Differentiated Dust Content for PVA 20, 120, and 200 Mesh

2025-10-17

Polyvinyl alcohol (PVA) is an essential polymer material in numerous applications, including dry-mix mortar, adhesives, and textile sizing. When selecting PVA products, users often focus on their degree of polymerization, alcoholysis degree, and mesh size to ensure core properties such as solubility, viscosity, and bond strength. However, dust content is a crucial, often overlooked indicator that directly impacts production safety, operator health, and material loss. The mesh size of PVA (e.g., 20, 120, 200 mesh) determines its particle size, and particle size is the primary factor determining dust content.

1.Why does PVA generate dust?

The dust content of PVA powder is primarily affected by its particle fineness (mesh size) and morphology:

Finer particles generate higher dust content. Products with larger mesh sizes (e.g., 200 mesh) have a higher proportion of fine particles and a greater ability to remain suspended in air, resulting in greater dust generation. Static electricity: Dry PVA powder is prone to static electricity during friction and conveying, which can exacerbate the suspension and dispersion of fine particles.

2. Definition and Significance of Dust Content

"Dust content" refers to the degree of fine dust suspended in the air during the handling of powder products due to their extremely fine particles. These fine particles (typically less than 10 μm or even 5 μm) not only cause material loss but, more importantly, impact operational safety, environmental cleanliness, and worker health.

Dust analysis of PVA products with different mesh sizes:

Mesh Size	20 mesh (PVA 088-05)	120 mesh (PVA 088-50S)	200 mesh (PVA-217S)
Particle Size Range	Approximately 800-900 μm	Approximately 100-150 μm	Approximately 50-80 μm
Particle Surface Area	Very Low Moderate	Moderate	Very High
Dust Level (Relative)	Low	Medium-Low	High
Photo
Aerodynamic Characteristics	Heavy particles with high inertia settle easily and are difficult to suspend.	120 mesh (CCP BP-24S) settle quickly, but will still fly at the moment of feeding.	Light particles are easily carried by air currents and remain suspended for a long time, forming a dust cloud.
Occupational Health Risks	Lowest risk. Dust is mostly non-inhalable and has minimal respiratory irritation.	Risk is manageable. General local exhaust ventilation and protective equipment are required.	Highest risk. Fine dust poses a high risk of lung entry and requires strict protection.
Dust Explosion Risk	Large particle size makes dust cloud formation difficult, resulting in a low risk.	Possesses some potential for dust cloud formation, resulting in a medium risk.	Dust cloud density easily reaches the lower explosion limit, resulting in the highest risk.
Production and feeding requirements	General ventilation is sufficient.	Local exhaust or dust hoods are required.	Efficient, enclosed feeding and specialized dust collection systems are essential.
Cost Factors	No additional dust suppression treatment is required.	Anti-caking agents (or granulation) may be required to reduce dust.	High costs must be invested in crushing, fine grading, and safety protection systems.
Properly controlling PVA dust levels is not only a safety requirement but also directly impacts production efficiency and product quality: Excessive dust concentrations can cause material loss and metering errors; Suspended particles entering the reaction system can lead to unstable emulsion polymerization or uneven film thickness; Dust deposition can accelerate equipment wear and affect long-term operational reliability.

Regardless of mesh size, all PVA powder handling practices should adhere to the following basic principles:

Avoid vigorous handling: Pour the material into the container slowly and steadily, avoiding pouring from a height to minimize interparticle friction and air turbulence. This is the simplest and most effective way to reduce dust generation.

Maintain ventilation in the work area: Local exhaust or exhaust systems must be installed near all feed ports and mixing equipment to capture generated dust at the source.

Adhere to chemical management practices: Although PVA has low toxicity, the storage, handling, and emergency response instructions in the Material Safety Data Sheet (SDS) should still be reviewed and followed.

Environmental cleanliness: Regularly clean accumulated dust from equipment and floors with an industrial vacuum cleaner. Never use compressed air to blow dust, as this will re-inflate accumulated dust, increasing the risk of explosion and inhalation.

3. Conclusion

In the production and use of PVA powder, dust management is the intersection of process control and safety assurance. Different mesh sizes require appropriate feeding methods and protective measures. Especially for fine powders above 120 mesh (CCP BP-20S), engineering approaches to dust control should be prioritized, rather than relying solely on personal protection. Through scientific particle size selection, process design, and environmental control, PVA product performance and production stability can be maximized while ensuring safety.

Website: www.elephchem.com

Whatsapp: (+)86 13851435272

E-mail: admin@elephchem.com

#Polyvinyl Alcohol 1788 #PVA 088-20 #Mowiol 23-88 #POVAL JP-18 #PVA 088-05S #CCP BP-05S #CCP BP-24S #PVA-217S #CCP BP-20S #PVA 088-50S

« Prev
1
2
3
4
...
50
Next »