Polyurethanes. IX. New Types of Highly Elastic Products: Vulcollans. Part 2

Abstract In the 6th Communication on the general subject of urethanes, it was shown that, in the presence of an excess of a diisocyanate, in particular naphthalene 1,5-diisocyanate, linear polyesters of adipic acid and simple glycols simultaneously lengthen and become converted into so-called polyester isocyanates, with the isocyanate groups as terminal groups of the chains. While this earlier work was concerned with the problem of cross-linking to form the synthetic elastomer, Vulcollan, with water as the agent, the work described in the present paper deals with other cross-linking agents, including glycols, aminoalcohols, diamines, and other bifunctional compounds. The mechanism of cross-linking is discussed for each of these cases, and it is shown that the chemical nature of the cross-linking agent has a decisive influence on the properties of the resulting Vulcollan product. The methods of preparation which are described point the way to new manufacturing processes, particularly the possibility of mol...