How to reveal latent degradation of coatings provoked by UV-light

被引：49

作者：

Larche, J-F. ^{[1
,2
,4
]}

Bussiere, P-O ^{[2
,3
]}

Gardette, J-L. ^{[1
,2
]}

机构：

[1] Univ Clermont Ferrand, Clermont Univ, Photochim Mol & Macromol Lab, F-63000 Clermont Ferrand, France

[2] CNRS, LPMM, UMR 6505, F-63173 Aubiere, France

[3] Clermont Univ, Ecole Natl Super Chim, Photochim Mol & Macromol Lab, F-63000 Clermont Ferrand, France

[4] PSA Peugeot Citroen, Direct Tech & Ind, F-78140 Velizy Villacoublay, France

来源：

POLYMER DEGRADATION AND STABILITY | 2010年 / 95卷 / 09期

关键词：

Photo-ageing; Water; Clearcoat; Cracking; Acrylic; Urethane; Melamine; ACRYLIC-MELAMINE COATINGS; AUTOMOTIVE PAINT SYSTEMS; PHYSICAL-PROPERTIES; FRACTURE ENERGY; CLEARCOATS; PHOTOOXIDATION; PHOTOLYSIS; POLYMERS; BEHAVIOR; NETWORK;

D O I：

10.1016/j.polymdegradstab.2010.05.005

中图分类号：

O63 [高分子化学（高聚物）];

学科分类号：

070305 ; 080501 ; 081704 ;

摘要：

This paper deals with predictions of the service life of the two main technologies used for automotive clearcoats: acrylic-melamine and acrylic-urethane. This work demonstrates that the UV-light irradiation leads to chain scissions and crosslinking for the unstabilised and stabilised formulations. Mechanisms are proposed to explain the dramatic increase in the values of the mechanical properties for the two technologies as a function of the ageing time. For a determined critical value of the mechanical properties, water acts to reveal the latent damage by leading to the formation of cracks. Moreover, when the polymer reaches a certain level of network densification due to UV-light irradiation, the system cannot accept the stress induced by the water inflation/deflation and cracks will occur. Other solvents were also tested to understand the effects of polarity on the formation of the cracks. (C) 2010 Elsevier Ltd. All rights reserved.

引用

页码：1810 / 1817

页数：8

共 24 条

[11] Relating laboratory and outdoor exposure of coatings III. Effect of relative humidity on moisture-enhanced photolysis of acrylic-melamine coatings [J].