pp, polypropylene English name: Polypropylene, abbreviation: PP, commonly known as: folding glue. Polypropylene is a representative of polyalphaolefin, a thermoplastic resin produced by the polymerization of propylene, the monomer is propylene CH2=CH-CH3. According to the different initiator and polymerization process, polypropylene can be divided into isotropic polypropylene and atactic polypropylene and intergeneric polypropylene three configurations. Isotropic polypropylene is easy to form a crystalline state, the degree of crystallinity is as high as 95% or more, molecular weight between 8-15 million, giving it a good resistance to heat and solvent resistance; random polypropylene at room temperature is an amorphous, slightly viscous white waxy, low molecular weight of 3,000-1,00000, the structure of the irregularity of the lack of cohesion, the application of the lesser.
PVC is polyvinyl chloride, the English abbreviation for PVC (Polyvinyl chloride), is vinyl chloride monomer (vinyl chloride monomer, referred to as VCM) in the peroxide, azo compounds, such as initiator; or under the action of light, heat, according to the free radical polymerization reaction mechanism of polymerization. Vinyl chloride homopolymer and vinyl chloride **** polymer collectively referred to as vinyl chloride resin. The material is a non-crystalline material.PVC material is often used with stabilizers, lubricants, auxiliary processing agents, colorants, anti-impact agents and other additives. It has non-flammability, high strength, resistance to weather changes and excellent geometric stability. PVC is highly resistant to oxidizing agents, reducing agents and strong acids. However, it can be corroded by concentrated oxidizing acids such as concentrated sulfuric acid and concentrated nitric acid and is not suitable for contact with aromatic hydrocarbons and chlorinated hydrocarbons.