期刊
JOURNAL OF MACROMOLECULAR SCIENCE PART B-PHYSICS
卷 50, 期 7, 页码 1460-1469出版社
TAYLOR & FRANCIS INC
DOI: 10.1080/00222348.2010.507453
关键词
crosslink density; mechanical property; natural rubber; NMR
资金
- Key Laboratory of Rubber-plastics, Ministry of Education, Qingdao University of Science and Technology
Crosslink density is an important structural parameter for cured rubber. Natural rubber (NR) vulcanizates with different crosslink densities were obtained through using different sulfur and accelerator amounts and different accelerator types. The crosslink density was characterized by an H-1-NMR technique and its influence on mechanical properties, such as Shore A hardness, 300% modulus, tensile strength, and elongation at break, of NR vulcanizates was investigated. The results showed that both the sulfur amount and the accelerator type and amount had an influence on the crosslink density of the NR networks. The relationship between total crosslink density and mechanical properties was also studied. The results, by changing either the sulfur or the accelerator amount, showed that tensile strength of NR vulcanizates reached maximum value when the total crosslink density was around 13.5 x 10(-5) mol/cm(3), equivalently the average molecular weight of the intercrosslink chains (Mc) was around 7000 g/mol. The maximum value of tensile strength came from the balance between contributions of crosslink joints and stretch-induced orientation and/or crystallization of intercrosslink chains. The study on influence of total crosslink density on Shore A hardness and 300% modulus of NR vulcanizates showed that they both increased linearly with the crosslink density, the slopes were 2.7 similar to 3.0 cm(3)/10(-5) mol and 0.27 similar to 0.31 MPa cm(3)/10(-5) mol for Shore A hardness and 300% modulus, respectively, whether the crosslink density was varied by sulfur or accelerator.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据