Numerous overseas purchasers inquire about selection differences among five vinyl acetate polymers. Liwei Chemical R&D Center releases a professional selection guide, distinguishing the five products from four dimensions including molecular monomer composition, physical properties, environmental resistance and applicable industries, helping overseas clients avoid product waste caused by incorrect material selection.
- PVAc (Polyvinyl Acetate Homopolymer): Composed of 100% vinyl acetate monomers, mainly water-based emulsion with strong adhesion and low cost. Limitations: poor water & low-temperature resistance, only suitable for indoor wood glue, paper coating and interior wall paint, not allowed for outdoor or high-humidity environments.
- VAE (Vinyl Acetate-Ethylene Copolymer Emulsion): PVAc modified with ethylene monomers, retaining eco-friendly water-based features while greatly improving water resistance, low-temperature tolerance and flexibility. Limitation: no barrier performance, mainly applied in construction waterproofing, cement modification, outdoor nonwoven adhesion and exterior waterborne coatings.
- EVA (Ethylene-Vinyl Acetate Thermoplastic Resin): Higher ethylene content, solid pellets processed by hot melting with excellent weatherability and impact resistance. Limitation: extremely poor oxygen barrier capacity, divided into three grades for PV encapsulation, foaming and wire cables, not applicable for barrier packaging.
- EVOH (Ethylene-Vinyl Alcohol Copolymer): High hydroxyl structure delivering top-tier oxygen & gas barrier performance in the industry. Limitation: weak hydrolysis resistance and brittleness when processed alone, must be co-extruded with EVA or PE, exclusively for food/chemical barrier packaging and automobile fuel tanks.
- PVB (Polyvinyl Butyral): High light transmittance, strong glass adhesion and outstanding impact resistance. Limitation: no self-adhesion and cannot form films independently, only used as interlayer raw material restricted to automotive & architectural safety glass. The guide also clarifies matching rules: EVOH + VAE composite for high-humidity packaging; VAE as primary material for outdoor construction; independent EVA for photovoltaic new energy; exclusive PVB for glass processing; PVAc for low-cost indoor adhesion. Multilingual versions of the full guide are uploaded to the technical library of official website for global clients to download.
