Disclosed is a high heat resistance and low viscosity polyoxytetramethylene glycol (PTMG) having the following characteristics (1) to (4): (1) a number average molecular weight of from 500 to 3000; (2) a molecular weight distribution of 1.8 or less in terms of the Mw/Mn ratio; (3) a content of high molecular weight PTMG molecules of from 2 to 5% by weight, wherein the high molecular weight PTMG molecules are PTMG molecules having molecular weights which are at least six times as large as the number average molecular weight of all PTMG molecules; and (4) a heteropolyacid content of from 10 to 900 ppb by weight.

Показан высокого гликоль polyoxytetramethylene сопротивления жары и низкой выкостности (PTMG) имея following характеристики от (1) до (4): (1) вес среднего номера молекулярный от 500 к 3000; (2) распределение молекулярного веса 1.8 или in terms of коэффициент Mw/Mn; (3) содержание молекул high molecular weight PTMG от 2 к 5% весом, при котором молекулы high molecular weight PTMG будут молекулами PTMG имея молекулярные весы которые по крайней мере 6 времен как больших как вес среднего номера молекулярный всех молекул PTMG; и (4) содержание heteropolyacid от ppb 10 до 900 весом.

 
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