The kinetics of the dibutyltin dilaurate catalyzed bulk polymerization of 4,4'-diphenylmethane diisocyanate (MDI) with poly-ecaprolactone were studied by infared spectroscopy and adiabatic temperature rise. The overall reaction order was found to change from 312 to 2 with increasing temperature. At temperatures above SOT, the order with respect to catalyst was found to decrease with concentration from 1 to 1/2. The results were consistent with a Michaelis Menten type kinetic scheme.

Glucoside derivatives of some UV absorbers have been prepared and investigated as photostabilizers for PVC in absence and in presence of Ca‐Zn stearate. The results indicate a reasonable stabilizing effect of the glucosides compared with the parent UV absorbers. The prepared glucosides were also investigated as thermal stabilizers for PVC and exhibited good thermal stability compared with that of commercial Ca‐Zn stearate heat stabilizer.

Viscosity was measured as a function of time for the polymerization of a reaction injection molding (RIM) type urethane system: 4,4′‐diphenyl methane diisocyanate (MDI) with a polyester triol and dibutyl tin dilaurate catalyst. Viscosity was found to be independent of shear rate. Isothermal viscosity rise was related to extent of reaction and to Mw, by branching theory. Isothermal results at several temperatures were able to predict viscosity rise under adiabatic conditions. The gel point test commonly used to evaluate RIM systems is shown to be essentially an adiabatic test.

Methacrylate‐based copolymers with 2‐hydroxyethyl methacrylate and 2,3‐epoxypropyl methacrylate, respectively, were synthesised and investigated as costabilisers for PVC. It was found that these polymers are capable of improving the induction time of PVC dehydrochlorination. This costabilising effect is dependent on the amount of functional groups which have been introduced into the copolymer. The new costabilisers interact with most used kinds of stabilisers and are capable of partly substituting the metal stabilisers.

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