THE ADHESIVE PROPERTIES OF CHLORINATED ULTRA-HIGH-MOLECULAR-WEIGHT POLYETHYLENE

Ultra-high molecular weight polyethylene (UHMW-PE) is well known for i ts abrasion and chemical resistance. Recently we developed a new appli cation for UHMW-PE as a liner in elastomeric hoses. It was found that the adhesion between UHMW-PE and elastomers such as ethylene-proplened iene monomer (EPDM) and styrene-butadiene rubber (SBR) is sufficient f or practical applications, but the adhesion to nitrile rubber (NBR) is poor. In order to improve the adhesion between NBR and the UHMW-PE li ner, (nascent) powder chlorinated polyethylenes were used as interlaye rs between UHMW-PE and NBR. These powder chlorinated polyethylenes are polymers with a dual nature and are composed of highly chlorinated po lyethylene segments compatible with NBR and polyethylene segments comp atible with UHMW-PE. In order to achieve sufficient adhesion, the chlo rine content of the chlorinated blocks should be at least 15 wt%. If t hese powder chlorinated UHMW-PEs have a chlorine content of greater th an or equal to 15 wt% in the chlorinated blocks, dilution with polyeth ylene hardly affects the adhesive properties, which is an advantage in the practical use of these materials as interlayers.