Effects of nano ZnO on strength and stability of unsaturated polyester composites

Abstract

ZnO--glass fiber--unsaturated polyester composites have been prepared. On exposure to the metal halide lamp, their resistance to ultraviolet (UV) degradation is evaluated. Experimental results show that ZnO can reduce the UV degradation of the unsaturated polyester matrix. ZnO can significantly retard the UV degradation process of the matrix resin, and can also increase the impact strength of the composites under the experimental conditions. Differential scanning calorimetry (DSC) analyses also indicate that the addition of ZnO to unsaturated polyester may retard the crosslink process and catalyze the decomposition of the resin. However, after more than 40 hr of UV irradiation, it was crosslinked. SEM fracture morphology shows that nano ZnO could hinder crack growth and induce more cracks, and when the content of ZnO reaches 6 wt%, the impact fracture mechanism changes abruptly and plastic deformation appears, which indicates that 6 wt% for ZnO in unsaturated polyester could be considered as the critical content. Around the critical content, the particles are near enough to interact with each other and this results in the change of fracture mechanism. The results also indicate that the proper content of ZnO added into an unsaturated polyester could prolong the durability and lessen the reject rate of transparent glass fiber--polyester composites.

Degradation of nano ZnO‐glass fiber‐unsaturated polyester composites

“…Thus series investigations on the effects of nano ZnO on unsaturated polyester are carried on. Previous paper, 27 showed that under exposure to the metal halide lamp, nano ZnO can significantly delay the UV degradation process of the matrix resin and can also increase the impact strength of the composites under the experimental conditions and can hinder crack growth and induce more cracks; when the content of ZnO reaches 6 wt %, the impact fracture mechanism changes abruptly and plastic deformation appears. The results indicate that the proper content of ZnO added into unsaturated polyester could prolong the durability and lessen the rejected rate of transparent glass fiber-polyester composites.…”

Surface and interface study of ZnO nanoparticles modified by octadecanol phosphate

“…The value of n is obtained from TG and the value of C is 1.85 × 10 19 . The number of the nanoparticles was estimated by TEM and XRD.…”

Influence of Aluminum Hydroxide Particles on the Properties of Modified Unsaturated Polyester

“…不饱和聚酯因价格低廉、加工容易和应用灵活 [1][2][3] ，而备受关注的一类工业化热固性树脂，它可应用 于片材、建筑材料、粘胶剂、涂料，且在建筑行业和 电子工业也发挥着重要作用 [4][5][6] 。 通常不饱和聚酯是由 二元醇、马来酸酐和其它二元酸缩聚反应制备而成， 合成方法灵活，原料来源广 [7][8][9] 。尽管不饱和聚酯拥有 众多优点，可室温储存、室温固化、低密度、材料透 明和绝缘 [10] ；但传统不饱和聚酯也存在某些缺点，相 应材料通常强度不高、韧性差、耐酸碱老化性差、易 燃 [11] 。大量文献报道，通过两种方法可改善传统不饱 和聚酯材料的性能。方法一：通过化学合成方法，在 不饱和聚酯分子链引入特殊基团，提高相应材料力学 性能或耐酸、碱老化性。在不饱和聚酯分子链结构上， 通过化学共价键引入丙烯酸酯基团 [12] 或双环戊二烯 结构 [13] 氢氧化铝颗粒对改性不饱和聚酯性能的影响 填充无机填料或化学助剂。适量的纳米二氧化硅、蒙 脱土和短丝纤维提高了不饱和聚酯的力学及热稳定 性 [14][15][16][17][18] …”