摘要:
Improved sealants and adhesives derived from polyisocyanates having aromatically linked -NCO groups are cured at ambient temperatures when combined with a curing agent comprising an imino- and enamino-functional compound. These two component resin systems may be employed in fabricating multi-substrate laminates, especially those comprising lignocellulosic and cellulosic materials, such as wood and paper.
摘要:
Improved sealants and adhesives derived from polyisocyanates having aromatically linked -NCO groups are cured at ambient temperatures when combined with a curing agent comprising an imino- and enamino-functional compound. These two component resin systems may be employed in fabricating multi-substrate laminates, especially those comprising lignocellulosic and cellulosic materials, such as wood and paper.
摘要:
A method for the preparation of cellular polymeric products which comprises reacting an organic polyisocyanate with an isocyanate-reactive composition, characterised in that the isocyanate-reactive composition comprises a blowing promoter which is a cyclic urea compound having at least one isocyanate-reactive substituent.
摘要:
A reaction system for use in making a reaction injection moulded elastomer, said system comprising the following components : (A) a polyisocyanate composition comprising a reaction product of a stoichiometric excess of an organic polyisocyanate and : (i) a polymeric polyol having an average nominal hydroxyl functionality greater than 2 and an average hydroxyl equivalent weight of from about 500 to about 5000, and (ii) a polymeric polyamine having an average nominal primary and/or secondary amino functionality of from about 2 to about 3 and an average amine equivalent weight of from about 500 to about 5000, the polyol and the polyamine having glass transition temperatures below room temperature. (B) an isocyanate-reactive composition comprising at least one imino-functional compound.
摘要:
A method for the preparation of rigid foams by reacting an organic polyisocyanate with an isocyanate-reactive material in the presence of a blowing promoter characterised in that the isocyanate-reactive material comprises at least one isocyanate-reactive cyclic carbonate or isocyanate-reactive cyclic urea, the reaction being performed in the presence of an inert insoluble organic liquid which is present as the disperse phase of an emulsion or a microemulsion, and in the presence of a metal salt catalyst.
摘要:
An internal mould release composition, suitable for use in the production of moulded articles by the RIM process, comprising : a) a metal salt of an organic acid, said metal salt having mould release properties, and b) a compatibilising amount of a guanidine or isourea compound of molecular weight below 1500.
摘要:
An internal mould release composition, suitable for use in the production of moulded articles by the RIM process comprising : a) a metal salt of an organic acid, said metal salt having mould release properties, and b) a polymer having a molecular weight of at least 1500 containing at least two guanidine or isourea groups of the formula : wherein A represents and wherein each of Q¹ and Q², independently, represents hydrogen, alkyl or cycloalkyl and each of Q³ and Q⁴, independently, represents hydrogen, alkyl, cycloalkyl, arakyl or aryl.
摘要:
An internal mould release composition, suitable for use in the production of moulded articles by the RIM process, comprising : a) a metal salt of an organic acid, said metal salt having mould release properties, and b) a compatibilising amount of an amidine or imidate compound.
摘要:
A polyisocyanate composition, suitable for use in the production of elastomers by the RIM process, said composition being the product of reacting an alcohol and/or thiol having an average hydroxyl and/or thiol functionality of from about 1.5 to about 4 and an average hydroxyl and/or thiol equivalent weight of at least 500 with at least 2 equivalents, per hydroxyl and/or thiol equivalent, of an organic polyisocyanate under such conditions that at least about 20 % of the initially formed urethane and/or thiourethane groups are converted to allophanate and/or thioallophanate groups.