硅酮结构密封胶的拉伸性能与耐久性

通过对7个建筑用硅酮结构密封胶样品的拉伸性能及相关性能的测试,讨论水、热、光-热-水的协同作用及位移能力等因素对其拉伸粘结性及耐久性的影响,各技术指标之间的对应关系,以及确定耐久性评价指标的可能性。结果表明,拉伸应力—应变曲线呈二次多项式函数关系;水的作用使拉伸粘结强度降低,但对伸长率的影响可能还取决于密封胶本身的内聚力和粘结活性之间平衡的结果;硬度、拉伸粘结强度和伸长率之间适当的协调可得到良好的弹性和位移性能。

By testing tensile and related properties of seven samples of structural silicone sealants, the following aspects are discussed that have influence on the tensile property and durability caused by water, heat, the synergistic effect of light-heat-water and displacement ability, the interrelation among technical data, and the possibility to determine an index to evaluate the durability. The result shows that the stress-strain curve of tensile test represents the multinomial function of quadratic equation; although the effect of water reduces tensile cohensional strength of sealant, the influence on the elongation might also lie on the result of the correspondence between cohesion and adhesive ability inherent in sealants themselves, the proper harmony among hardness, tensile strength and elongation can achieve better elastic and displacement ability.