Polyolefins polyallomer

The polyolefins are high-molecular-weight hydrocarbons. They include low-density, linear low-density, and high-density polyethylene, polyallomer, polypropylene, and polymethylpentene. All are break-resistant, nontoxic, and... 

PP/PA (polypropylene/polyallomer). These plastics are similar to polyethylene, but each unit of their chains has a methyl group attached. They are translucent, autoclavable, and have no known solvents at room temperature. They are slightly more susceptible than polyethylene to strong oxidizing agents. They offer the best stress-cracking resistance of the polyolefins. Products made of polypropylene are brittle at ambient temperature and may crack or break if dropped from benchtop height. 

Olefin copolymers are a group of polyolefin thermoplastics made by copolymerization of olefiiuc polymers. This family includes polyallomers, ionomers, ethylene vinyl acetate (EVA), ethylene ethyl acrylate (EEA), ethylene n-butyl acrylate, ethylene hexane (EH), and ethylene butene (EB). 

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