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对不同种类和数量的填料,比如炭黑N220和白炭黑,对SBR分子结构和力学特性的影响,以及硫化过程对填充SBR体系的影响,通常是以“Hahn回波”技术和NMR(核磁共振)技术的旋转结构纵向松弛T1ρ作为力学测试方法,对宏观和微观结果在数量上对比分析来研究的。基于弹性网络横向松弛的理论模型得到的计算结果显示填料整体或者填料聚集体表现得像其它交联点一样,因此导致交联点分子量Mc的降低,相互交联网络的增加,或者看成是悬挂自由链的降低,最终导致交联网络模量Gc的增大,这种程度取决于填料的类型,尤其是数量的影响。与填充硅烷偶联剂的丁苯胶相比,填充炭黑N220的SBR由于它更强的结合能力或者是吸附力显示有更多的交联网络链,但却因不均质的程度较高使得交联密度下降。部分和全部链的活动能力与填料的相关性,在交联和未交联的两个SBR体系中明显不同,这主要归因于在SBR基体中填料对发生化学交联反应的束缚。最近,通过填料聚集体补强以及应力诱导的聚集体破坏被认为与一种关于橡胶弹性的管状模型有关,这种模型是针对填充橡胶在单轴应力应变测量时的典型的应力松弛效应而建立的。用于评价的材料参数可以表征交联密度以及填料特有的聚合物-填料联接。交联网络结点的计算密度在实验误差内完全与NMR测得的值一致;不同的值可以被用作评估不同类型交联和链缠结的含量。最后,一些相关的观测结果可以用不同的物理模型图解。
The effect of various types and quantities of fillers, such as carbon black N220 and silica, on the molecular structure and mechanical properties of SBRs and the effect of vulcanization on the SBR loading system are usually based on the “Hahn Echo” technique and NMR (Nuclear magnetic resonance) technology of the longitudinal structure of the relaxation T1ρ as a mechanical test method, the macroscopic and microscopic results of quantitative analysis to study. The calculation results based on the theoretical model of elastic web transverse relaxation show that the whole filler or filler aggregate behaves like other crosslinking points, thus resulting in a decrease of the molecular weight Mc at the crosslinking point, an increase of mutual cross-linking networks, or as a suspension The reduction of the free chain eventually leads to an increase of the crosslinked network modulus Gc, which depends on the type of filler, in particular the quantity. Compared with SBR filled with silane coupling agent, SBR filled with carbon black N220 shows more cross-linked network chains because of its stronger binding ability or adsorption force, but due to the higher degree of heterogeneity So that the crosslinking density decreased. Part and total chain activity and filler correlation, in the two cross-linked and non-cross-linked SBR system significantly different, mainly due to SBR matrix filler chemical cross-linking reaction bound. Recently, the reinforcement by the filler aggregates and the stress-induced aggregate destruction are considered to be related to a tubular model of rubber elasticity that is established for the typical stress relaxation effect of filled rubber upon uniaxial stress-strain measurement of. The material parameters used for the evaluation can characterize the crosslinking density and the filler-specific polymer-filler coupling. The calculated density of crosslinked network nodes is exactly the same as that measured by NMR within experimental error; different values can be used to evaluate the content of different types of crosslinks and chain entanglements. Finally, some related observations can be illustrated by different physical models.