Titanate or Zirconate coupling agents work in the melt via coupling and catalysis to regenerate recycle or regrind polymers. It will be shown that coupling is accomplished via proton coordination to non-silane reactive substrates such as CaCO3 and carbon black without the need of water of condensation as with silanes. Catalysis data will show that the additives provide a means for post reactor, in-situ metallocene-like repolymerization catalysis of a filled or unfilled polymer during the plastication phase resulting in: significantly faster thermoplastic processing at lower temperatures; lower polymer recrystallization time; the copolymerization of dissimilar polymers providing significant increases in elongation and modulus; and the regeneration of regrind or recycled polymers to virgin properties allowing products such as blow molded HDPE to increase regrind levels while being able to down gauge to equivalent strength. The catalysis effect is shown to be permanent and recyclable. For example, the melt index of a LDPE/PP-50/50 alloy without titanate climbs from 17 to 37 when subjected to six heat cycles in a twin screw while the blend with 0.2 wt% titanate rises to only 24. Literature search results show that commingled post-consumer waste plastics melt blended with Pinus Radiata fibre and neoalkoxy titanate form composite materials with higher tensile strengths of the order of 30% to 50%. Coupling agent liquid, powder and pellet forms; dosage; data and applications methodology in compounding, injection and blow molding are discussed.
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