Mechanism of moisture-cure of isocyanate reactive hot melt adhesives

被引：34

作者：

Comyn, J

Brady, F

Dust, RA

Graham, M

Haward, A

机构：

[1] Loughborough Univ Technol, Inst Polymer Technol & Mat Engn, Loughborough LE11 3TU, Leics, England

[2] Natl Starch & Chem Ltd, Slough SL1 4DF, Berks, England

来源：

INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES | 1998年 / 18卷 / 01期

关键词：

(A) hot melt; (D) cure/hardening;

D O I：

10.1016/S0143-7496(98)80004-3

中图分类号：

TQ [化学工业];

学科分类号：

0817 ;

摘要：

The depth of moisture cure (z) has been measured for lap joints in aluminium with two isocyanate moisture curing hot melt adhesives. With one adhesive, z is proportional to the square root of time, but with the other there is a time-lag before cure commences. Skins form when the adhesives are exposed to moist air, and their thicknesses (sigma) are proportional to root of time of exposure. The depth of cure is given by z = sigma = (2PV pt)(1/2), where P is the permeability coefficient of water in cured sealant, V is the volume of sealant which reacts with 1 mole of water, p the vapour pressure of water and t the time; this is after correction for the time-lag. The final state of cure is independent of relative humidity. One adhesive cures more rapidly than the other, and the main factor responsible for this is its higher water permeability. (C) 1998 Elsevier Science Ltd. All rights reserved.

引用

页码：51 / 60

页数：10