Method of joining plastic pipe

A method of joining polyethylene pipe sections which comprises:

• 1. heating the internal wall of the end of a high molecular weight polyethylene pipe section at about 470.degree.-530.degree. F. for a period sufficient to soften the wall,
• 2. heating the external wall of the insert portion of a polyethylene polymer fitting having an annular insert portion with an outer diameter substantially the same as the inner diameter of the pipe section to be joined thereto and a shoulder portion with a larger diameter than the insert portion, at about 470.degree.-530.degree. F. for a period sufficient to soften the external wall surface of the insert, said fitting being formed of a reaction product of a polymer or copolymer of ethylene having a density of 0.940-0.950, with from about 5.0 to about 15.0 percent by weight of the polymer or copolymer of ethylene of a butyl rubber and from about 0.30 to about 2.5 percent by weight of the ethylene polymer or copolymer of a bifunctional phenolic composition having ortho functionality and the para position of the phenol ring substituted with an inert hydrocarbon radical selected from the group consisting of alkyl, aryl, alkyl-aryl and arylalkyl radicals of up to 16 carbon atoms,
• 3. removing the pipe end and the fitting from the heat source,
• 4. fitting the insert portion of the coupling into the pipe section so that the edge of the pipe substantially abuts the shoulder portion of the fitting, and
• 5. crimping the pipe to the insert to cause fusion therebetween.