Ethylene Vinyl Acetate

Polyvinyl alcohol (PVA) is a fundamental raw material for vinylon production and is also used in the production of adhesives, emulsifiers, and other products. In the PVA production process, solution polymerization is used to ensure a narrow degree of polymerization distribution, low branching, and good crystallinity. The VAM polymerization rate is strictly controlled at approximately 60%. Due to the control of the polymerization rate during the VAM polymerization process, approximately 40% of the Vinyl Acetate Monomer (VAM) remains unpolymerized and requires separation, recovery, and reuse. Therefore, research on VAM recovery process is a crucial component of the PVA production process. There is a polymer-monomer relationship between Ethylene Vinyl Acetate (EVA) and vinyl acetate monomer (VAM). Vinyl acetate monomer is one of the basic raw materials for making ethylene vinyl acetate polymer.   This paper uses the chemical simulation software Aspen Plus to simulate and optimize the VAM recovery process. We studied how process settings in the first, second, and third polymerization towers affect the production unit. We found the best settings to save water used for extraction and lower energy consumption. These parameters provide an important theoretical basis for the design and operation of VAM recovery.   1 Vinyl Acetate Monomer Recovery Process 1.1 Simulation Process This process includes the first, second, and third polymerization towers in the vinyl acetate monomer recovery process. The detailed flow diagram is shown in Figure 1.   1.2 Thermodynamic Model and Module Selection The vinyl acetate monomer recovery unit of the polyvinyl alcohol plant primarily processes a polar system consisting of vinyl acetate, methanol, water, methyl acetate, acetone, and acetaldehyde, with liquid-liquid separation between vinyl acetate and water. The main equipment in the vinyl acetate monomer recovery unit of the polyvinyl alcohol plant was simulated using Aspen Plus software. The RadFrac module was employed for the distillation tower, and the Decanter module for the phase separator.   2 Simulation Results We ran a process simulation on the vinyl acetate monomer recovery unit in the polyvinyl alcohol plant. Table 3 shows a comparison of the simulation results and actual values for the main logistics. As shown in Table 3, the simulation results are in good agreement with the actual values, so this model can be used to further optimize the process parameters and process flow.     3 Process Parameter Optimization 3.1 Determination of the Amount of Stripping Methanol Polymerization Tower 1 takes out vinyl acetate monomer (VAM) from the stream that remains after polymerization. It uses methanol vapor at the bottom for heat. The right amount of methanol is important for how well the tower works. This study looks at how different amounts of methanol affect the mass fraction of PVA at the tower's bottom and the mass fraction of VAM at the top, assuming the feed stays the same and the tower's design is constant.   As shown in Figure 2, when the heat capacity needed for separation in Polymerization Tower 1 is satisfied, raising the stripping methanol amount lowers the PVA mass fraction at the bottom and the VAM mass fraction at the top. The stripping methanol amount has a linear relationship with the PVA mass fraction at the bottom and the VAM mass fraction at the top.   3.2 Optimization of the Feed Position in Polymerization Tower 2 In Polymerization Tower 2, an extractive distillation tower, the locations where the solvent and feed enter greatly affect how well the separation works. This column uses extractive distillation. Based on the physical properties of the extractant and the mixed feed, the extractant should be added from the top of the column. Figure 3 shows how the mixture feed position affects the methanol mass fraction at the top and the reboiler load at the bottom, keeping other simulation settings the same.   3.3 Optimizing the Extraction Water Amount in Polymerization Column 2 In Polymerization Column 2, extractive distillation is used to separate vinyl acetate and methanol azeotrope. By adding water to the top of the column, the azeotrope is disrupted, allowing for the separation of the two substances. The extract water flow rate has a big impact on how well Polymerization Column 2 separates these materials. With consistent simulation settings, I looked at how the amount of extract water affected the methanol mass fraction at the top and the reboiler load at the bottom of the column. The results are shown in Figure 4.   3.4 Optimizing the Reflux Ratio in Polymerization Column 3 In Polymerization Column 3, the reflux ratio is important for separating vinyl acetate from lighter substances like methyl acetate and trace water. This boosts the quality of vinyl acetate obtained from the side stream. We kept the simulation settings constant and studied how the reflux ratio affects both the mass fraction of vinyl acetate from the side stream and the reboiler load. The calculation results are shown in Figure 6. Maintaining the polymerization tower's reflux ratio around 4 helps ensure the vinyl acetate from the side line meets quality standards and keeps the reboiler load low.     4. Conclusion (1) Using AspenPlus software, a suitable thermodynamic model is selected to simulate the entire process of vinyl acetate monomer recovery of the polyvinyl alcohol plant. The simulation results are in good agreement with the actual values and can be used to guide the process design and production optimization of the plant. (2) Based on the establishment of a correct process simulation, the influence of the process parameters of the polymerization tower 1, polymerization tower 2, and polymerization tower 3 on the plant is investigated, and the optimal process parameters are determined. When vinyl acetate meets the needed separation standards, we can save on extraction water and lower energy use.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

🔬 At a molar fraction of 5% vinyl acetate, the mechanical properties of EVA (ethylene vinyl acetate copolymers) become very similar to those of soft PVC.EVA is flexible in its own right, which gives it a number of advantages, such as the disadvantage of avoiding the migration of plasticizers, which is the main reason for the gradual replacement of PVC.     💪 These copolymers have a higher modulus and better processing properties than typical elastomers and do not require vulcanization considerations. Polyvinyl alcohol (PVA 088-50 & PVA 2488) can be obtained by hydrolysis of polyvinyl acetate. Poly(vinyl alcohol) is an atactic cubic polymer but does not disrupt the lattice structure due to the small hydroxyl groups. Therefore, ester bases that are not sufficiently hydrolyzed reduce crystallinity and the number of intermolecular hydrogen bonds.   💧 Highly hydrolyzed poly(vinyl acetate) (containing fewer unhydrolyzed ester groups) has a higher crystallinity. As the degree of hydrolysis increases, the molecules become easily crystallized. If these molecules are not sufficiently dispersed before dissolution, hydrogen bonding will cause them to associate with each other. In order to achieve hydrolysis levels above 98%, manufacturers need to operate at a low temperature of 96°C to ensure that the larger molecules have sufficient thermal energy to dissolve.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

EVA( Ethylene Vinyl Acetate) resin is short for ethylene acetate-ethylene resin, which is a polymer made of ethylene acetate and ethylene monomer. According to the different contents of ethylene acetate, the copolymers of ethylene and ethylene acetate were divided into EVA resin, EVA rubber and VAE emulsion. .Products containing less than 40% vinyl acetate are EVA resins.    EVA resin has good softness and shock-absorbing properties. It is one of the materials widely used in the footwear manufacturing industry and can be used to make soles, insoles, uppers and other components. It is also often used as a cushioning material, such as knee pads, wrist pads, and ankle pads in sporting goods, as well as car seat pads, motorcycle seat pads, etc.   EVA resin can be molded through various processing methods, such as extrusion, injection, calendering, etc., and it also has shock-absorbing properties. It is an excellent packaging material such as protective film, liner, protective cover, etc. to protect items during transportation and storage. No damage is caused during the process.   The chemical resistance of EVA resin can resist the erosion of many chemical substances. In medicine, EVA resin is often used to make medical instruments and equipment, such as surgical instruments, medical tapes, gloves, etc. It has good chemical resistance and transparency, and meets hygiene and health requirements. It is also an insulating material for electronic products, such as cable insulation tubes, insulating gaskets, etc. It can also be used as a protective material for batteries, with excellent chemical resistance and heat insulation properties.   In terms of building materials, EVA resin can be used as building materials, such as sound insulation panels, heat insulation panels, etc. It has good sound absorption, heat insulation and weather resistance properties, and can improve the comfort of buildings.   Agricultural use EVA resin can be used as agricultural covering film. It has good weather resistance and light transmittance, and can protect crops from bad weather.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

Ethylene Vinyl Acetate (EVA) film is a thermosetting and sticky film, mainly used in the middle of laminated glass. It has the characteristics of high transparency, high adhesion, good durability and easy storage. ‌ ‌High transparency allows light to penetrate better, reducing light energy loss and improving photoelectric conversion efficiency.   ‌High adhesion, able to firmly bond various materials, effectively ensuring the stability between components.   ‌Good durability, able to resist high temperature, moisture, ultraviolet rays and other environmental factors, ensuring long-term use.   ‌Easy to store, it can be stored at room temperature and is not affected by humidity and water absorption.   ‌Low melting point, easy to flow, suitable for lamination process of various glass, such as patterned glass, tempered glass, curved glass, etc.   Strong sound insulation effect. Compared with PVB film, EVA film has stronger sound insulation effect, especially for high-frequency sound.   Due to various excellent properties, EVA film is widely used in current components and various optical products, especially playing an important role in the packaging of solar photovoltaic modules.‌Solar photovoltaic module packaging, EVA film is used to fix solar cells and provide insulation protection, optical coupling, and provide moderate mechanical strength and heat conduction paths.   In recent years, with the rise and development of the global photovoltaic industry, the market demand for EVA(V6110S) has increased year by year, which has broad market prospects. There is also great room for improvement in the domestic EVA film market.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

Ethylene Vinyl Acetate (EVA) is a lightweight material. Compared with other shoe materials such as rubber and leather, it is lighter in texture and has excellent softness, which can better fit the shape of the foot and make the foot feel more comfortable. Very beneficial to children's foot development. Many children's shoes are made of EVA material to provide comfort and support.   EVA shoe materials have good shock-resistant properties, which can reduce the impact on the feet during walking and running. Effectively reduce foot fatigue and protect feet from injury. It also has excellent abrasion resistance and can withstand the wear and tear of daily use. Many well-known sports shoe brands use EVA to make midsoles and insoles. Its lightweight and shock-resistant properties make sneakers more suitable for sports and workouts. EVA material also has good breathability and is also very suitable for making summer sandals.   EVA material has good waterproof properties and has good adaptability to wet and beach environments. Therefore, many beach shoes are made of EVA material, which can provide comfort and anti-slip effect in wet and sandy environments.   Manufacturing EVA shoe materials usually includes the following steps: EVA particles are usually white or transparent, and colors can be added as needed; Heat it to a molten state, and then the melted EVA is injected into the mold through an injection molding machine; The injected EVA material is further pressed and molded to obtain the final shoe material shape; The pressed shoe material needs to go through a cooling process to solidify and maintain the desired shape; Then trim to remove excess material so that it achieves the final look.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

No, Ethylene Vinyl Acetate (EVA) is not the same as Vinyl Acetate-Ethylene (VAE,DA-310). While both EVA and VAE are copolymers of ethylene and vinyl acetate, they have different structures and properties.   EVA is a copolymer of ethylene and vinyl acetate, where the vinyl acetate content typically ranges from 5% to 50% by weight. It is a flexible, rubbery material commonly used in various applications such as footwear, packaging, and solar cell encapsulation due to its excellent flexibility, low-temperature toughness, and UV resistance. VAE, on the other hand, refers to a different type of copolymer formed by the polymerization of vinyl acetate and ethylene. In VAE, the vinyl acetate content is generally higher than in EVA, typically ranging from 10% to 60% by weight. VAE is often used as a binder or adhesive in construction materials such as paints, coatings, adhesives, and textiles.   So, while both EVA and VAE are copolymers of ethylene and vinyl acetate, they have different compositions and applications.