Entec Polymers offers an array of both branded prime and generic prime Polypropylene (PP) options in our commodity polymer portfolio. Polypropylene has the lowest density among commodity plastics and is one of the most used polymers today due to its versatility in rigid and flexible applications. Our HYPRO® branded Polypropylene is an excellent option for customers seeking cost-effective, top-quality solutions for rigid and flexible applications.
Homopolymer PP has the highest level of crystallinity of the three types and is therefore the stiffest and strongest. It is translucent and has good contact clarity with liquids. It has poorer impact resistance compared to the other two polypropylene types, especially below 35 °F.
ADVANTAGES OF HOMOPOLYMER PP:
Random copolymers introduce a small amount of ethylene into the homopolymer PP backbone which disrupts the crystallinity. This results in the random copolymer being the clearest and most flexible of the three polypropylene types. Increased ethylene content improves clarity. Random polypropylene will have better room temperature impact than the homopolymer, but same relatively poor impact resistance at low temperatures.
ADVANTAGES OF RANDOM COPOLYMER:
Impact copolymers disperse ethylene propylene (EPR) rubber nodules into the homopolymer PP matrix providing good impact resistance at room and cold temperatures. These polymers provide an intermediate stiffness and appear opaque. The more ethylene monomer added, the higher the impact resistance and conversely the lower the stiffness of the resulting polymer.
ADVANTAGES OF IMPACT COPOLYMER: