PDF(Pubmed)
Abstract：
Degradation of polymer composites is a significant problem in many engineering aspects. Due to the interaction of various degradation factors during the exploitation of composites, a synergistic effect of destruction is observed. The article describes the phenomena occurring in glass fiber reinforced polyester laminates under the influence of ultraviolet radiation (UV) in an aquatic environment. The laminates were exposed to UV-A, UV-B and UV-C radiation for 1000 h in free-air and underwater conditions. During the test, the materials were immersed at stable depth of 1 mm and 10 mm, respectively. The three-point bending tests performed on the samples after being exposed to UV showed an increase in the flexural strength of the composites. Simultaneously, degradation of the outer surface layer was observed. The degradation removed the thin resin film from the surface which resulted in a direct exposure of the reinforcing fibers to the environment. The transformations taking place in the deeper layers of the composite increased the mechanical strength due to the additional cross-linking reactions excited by the energy arising from the radiation. Moreover, the formation of polymer structures from free styrene remaining after the technological process and the occurrence of free radical reactions as a result of the cage effect was also observed.
摘要：
聚合物复合材料的降解是许多工程方面的重要问题。由于复合材料开发过程中各种降解因素的相互作用,观察到破坏的协同效应。本文介绍了在水生环境中，在紫外线辐射（UV）的影响下，玻璃纤维增强聚酯层压板中发生的现象。将层压板暴露于UV-A，UV-B和UV-C辐射1000小时在自由空气和水下条件。在测试过程中,材料浸入1毫米和10毫米的稳定深度，分别。在暴露于紫外线后对样品进行的三点弯曲测试显示复合材料的挠曲强度增加。同时,观察到外表面层的降解。降解将树脂薄膜从表面上除去,这导致增强纤维直接暴露于环境中。由于由辐射产生的能量激发的附加交联反应，在复合材料的较深层中发生的转变增加了机械强度。此外，还观察到工艺过程后残留的游离苯乙烯形成聚合物结构，以及由于笼状效应而发生的自由基反应。
