Ha acidity function

A good correlation has been found between pKa values for a series of pyridine 1-oxides and the corresponding pyridines. Weakly basic pyridine 1-oxides that protonate in the H0 region have been shown to follow the HA acidity function. Some of these have been used to extend the HA scale and to determine its variation with temperature. 

A polymer alloy was prepared by Lavengood, PateL and Padwa [6]. This alloy is comprised of ABS with polybutadiene rubber, a polyamide such as nylon-6 or nylon-11, and a compatibilizer. The polyamide and ABS are immiscible. The compatibilizer is selected in a fashion that it is either partially or completely miscible with the graft copolymer, and has acid functional groups that can be made to react with the end groups of polyamides. This can be a terpolymer of styrene, acrylonitrile, and maleic acid. The resulting polymer alloy has been a successful product in the commercial arena under the name of Triax 1000. The performance properties were a step change improvement. 

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