Chlorinated Polyethylene—a Comprehensive Characterization

Chlorinated polyethylene elastomers, a relatively new series of polymers, are derived from a high density polyethylene backbone which has been chlorinated via a free radical aqueous slurry process. Polymers are available which vary in percent chlorine (36-48%), in molecular weight, and in inherent crystallinity. Unfortunately, these basic polymer properties are inadequate to describe the performance of chlorinated polyethylene elastomers on a practical basis. The current study characterizes chlorinated polyethylene elastomers as general purpose oil, heat and ozone resistant elastomers. Reference is made to more familiar rubbers for comparative purposes only. Once the polymer's position within the above frame of reference is established, the technology with which one compounds chlorinated polyethylene for specific properties is investigated. Because of the saturated polymer chain, the necessity of free radical curing systems is outlined. Both black and non-black filler systems are introduced. This flexibility gives the compounder an excellent balance of properties including a realistic service temperature from —60° F to 300° F.