硫化剂TCY对丙烯酸酯橡胶的硫化特性

研究了硫化剂ＴＣＹ对丙烯酸酯橡胶（ＡＣＭ）的硫化特性。通过改变硫化温度,分析了硫化反应活化能,并研究了硫化剂及助硫化剂在不同用量下的硫化特性和硫化胶性能。试验结果表明,硫化剂ＴＣＹ对活性氯型ＡＣＭ具有低温快速硫化能力,其硫化反应活化能为６０５２ｋＪ·ｍｏｌ－１;添加少量硫黄作为ＡＣＭ的助硫化剂,可有效提高胶料的硫化速度和交联度,硫化胶的综合性能良好     

硫化促进剂CBS合成新工艺

研究了一种用未经精制的粗Ｍ与环己胺反应硫化促进剂ＣＢＳ的新工艺。新工艺具有原料消耗低，经济效益好的特点，同时还避免了因精制原料，Ｍ而带来的大量废水，对该工艺最佳条件进行了讨论。     

MVQ/ACM并用胶料硫化特性的研究

研究硫化剂DCP、硫化剂双2 5和两者并用硫化体系对甲基乙烯基硅橡胶(MVQ)/ACM并用胶料硫化特性的影响。结果表明,硫化剂DCP和硫化剂双2 5硫化的胶料最大转矩(MH)均随硫化剂用量的增大先增大后减小,硫化效果均较好。采用硫化剂双2 5/硫化剂DCP并用体系硫化的胶料能获得更快的硫化速度,且MH较大;当硫化剂双25/硫化剂DCP并用比为0.15/0.5时,MH高达20 dN.m,比硫化剂双25或硫化剂DCP单用时提高约30%。进行二段硫化有利于提高MVQ/ACM并用胶的物理性能,二段硫化温度为200℃时,硫化时间以3~4h为宜。     

硫化仪

硫化仪（curometer或vulcameter）也被称为流变仪（rheometer），是全程测定胶料硫化过程的仪器，在橡胶工业中被广泛采用。以前，为了得到胶料的全套硫化数据（包括焦烧时间、正硫化时间、硫化平坦期、过硫点等），往往需要冗长的时间，进行测定、记录、计算和绘图，付出大量劳动。单测一个正硫化点就需要对至少5～6个试样进行逐项测试，最后根据点绘的曲线才能找出正硫化点。而有了硫化仪，只要借助于1个试样，仅通过一次试验就能完成上述各项测试，获得代表硫化轨迹的硫化曲线，并提供各项硫化性能数据，让配方人员一目了然。所以，硫化仪的优点可以用“多、快、好、省”四个字来归纳。     

应用变温分析方法探讨轮胎的硫化特性

以９．００－２０轮胎为例,根据在实际硫化过程中所测的轮胎各部位胶料的不等温度－时间曲线,在实验室内用ＲＰＡ－２０００型橡胶加工分析仪对轮胎相应部位胶料进行不等温硫化的特性分析,通过所测数据计算出所用胶料的过硫化程度,并提出相关部位胶料西方及生产工艺的改进意见。     

集成橡胶硫化特性的研究

对集成橡胶(SIBR)硫化特性进行研究,并与异戊橡胶(IR)、丁苯橡胶(SBR)和顺丁橡胶(BR)进行对比。结果表明:与IR,SBR和BR相比,未补强SIBR胶料焦烧时间较长,硫化速率较慢;炭黑补强SIBR胶料焦烧时间明显缩短,硫化速率增大,硫化平坦性较好。SIBR在硫化温度超过170℃时存在明显的硫化返原现象,并导致相应硫化胶的压缩疲劳温升和动态损耗增大,其最适宜的硫化温度为150℃。     

仿真分析技术在橡胶弹簧硫化时间设计中的应用

阐述传统计算法和仿真分析法计算橡胶制品正硫化时间的原理,以某橡胶辅助弹簧为研究对象,分别用两种方法计算其正硫化时间,并用溶胀指数和垂向刚度试验进行对比验证。结果表明,仿真分析法能较好地预测胶料硫化程度,可减少产品试模次数,降低研发成本。     

有转子硫化仪滞后现象的分析

分析了有转子硫化仪测试胶料硫化特性时出现的第1次试验时间滞后现象。实验分析和传热分析计算得出,硫化仪模胶充满空气时的转子表面温度比充满胶料时低,从而导致硫化仪第1次试验胶料的硫化速度慢,表面为胶料硫化特征时间(ts1,t10,t50和t90等）滞后。在试验前延长硫化仪模腔保温时间可缩短第1次试验的滞后时间。     

硫化体系对天然橡胶性能的影响

采用常规硫化体系(CV)、半有效硫化体系(SEV)和有效硫化体系(EV)制备了不同的NR(天然橡胶)硫化胶。着重探讨了不同硫化胶的微观形貌、200%定伸强度、撕裂强度、拉伸强度、断裂伸长率和交联密度。研究结果表明:SEV硫化胶的微观形貌相对较好,填料能均匀分散在基体中;在其他条件保持不变的前提下,当w(NOBS)=w(硫)=2.0%(相对于NR质量而言)时,相应的未老化SEV硫化胶的撕裂强度(78 kN/m)相对最大;SEV硫化胶的交联密度大于CV硫化胶和EV硫化胶,并且适当增加交联密度能有效提高其综合性能,从而为开发新一代轮胎等复合材料奠定了基础。     

Effect of vulcanization temperature and vulcanization systems on the structure and properties of natural rubber vulcanizates

The effect of vulcanization temperature (150°–180°C) on the structure and technical properties of gum natural rubber vulcanizates with four different 2-(morpholinodithio)-benzothiazole: sulphur ratios (A, 0.6:2.4; B, 1.5:1.5; C, 2.4:0.6; D, 3.0:0.0) at the respective optimum cure times has been determined. The influence of cure temperature on (a) the chemical crosslink density; (b) the distribution of crosslink types; (c) the extent of sulphidic main chain modifications and (d) the zinc sulphide formation was investigated. Results show that elevated cure temperatures produce a network with lower crosslink density, in particular a lower polysulphidic crosslink density. The formation of intramolecular sulphidic groups and zinc sulphide increase with increasing cure temperatures. The possibility of chain scission during vulcanization, as examined by a quantitative analysis of the sol—gel data, was found to be negligible. The network results have been correlated with the technical properties.     

Creep and recovery of unvulcanized natural rubber

The creep and recovery behaviour of unvulcanized natural rubber, both filled and unfilled, is investigated under low stresses in tension at room temperature. A method based on the Boltzmann superposition principle has been used to predict the creep function from measurements of its recovery after release from a range of constant loads each held for various lengths of time (t₁). For both gum and carbon black-filled rubbers of a given Mooney viscosity, the technique resurrects a master creep curve which is found to be independent of t₁. Although this has the same general shape as the experimental creep curve the two differ significantly, except for the filled rubber at small stresses. The discrepency is ascribed to non-linear effects mainly associated with the tendency of the unvulcanized rubbers (especially the gum rubber) to flow at high applied tensile stresses and long times. Under such conditions the superposition principle is no longer valid. This non-linear effect due to flow can be approximately corrected for by substracting the experimentally measured permanent set from the creep and recovery data before treating the remainder with the Boltzmann superposition principle. This method of correction yields good agreement between the revised experimental creep and the derived creep compliances for gum rubbers up to σ=0.50 kg cm^?2, and for black-filled rubbers up to σ=0.78 kg cm^?2.     

Influence of prolonging vulcanization on the structure and properties of hard rubber

This research on vulcanization illuminates the structure–property relationship of hard rubber with prolonging vulcanization. At the early stage of curing, polysulfur reacts with styrene–butadiene rubber (SBR) macromolecules to form chemical crosslink, as evidenced by the significant increase of modulus during vulcanization. The chemical crosslink is followed by a large amount of interchain attraction, which is due to the modification of SBR macromolecules by combined sulfur. The combined sulfur is formed by the reaction of sulfur atom with SBR backbone, which improves the polarity of SBR macromolecules since sulfur is polar. The influences of chemical crosslink and interchain attraction on the mechanical properties, thermal properties, dynamic mechanical properties, and fracture morphology were analyzed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

超声硫化的实验研究

成功地利用超声波对天然橡胶进行了硫化，所得试件展示了与传统硫化方法制得的试件相同的硫化，所得试件展示了与传统硫化方法制得的试件相同的性能。但该工艺表现出许多传统硫化方法所不具备的优点。用滞后能量损失理论及声化学作用，解释了超声硫化的机理。     

Some factors affecting the electrical properties of carbon-black-loaded butyl rubber during vulcanization

Butyl rubber mixtures loaded with 70 phr general purpose furnace black (GPF) and tetramethyl thiuram disulphide (TMTD)/S as vulcanizing system were prepared. The kinetics of their electrical conductivity development during the vulcanization process were followed by using an especially devised system. It was found that the increase in the electrical conductivity during vulcanization obeys an exponential growth function with time constant τ, which markedly decreases with increasing vulcanization temperature as well as with the efficiency of the vulcanizing system. After completion of the vulcanization process, about 80 min, the samples obtained possess reasonable stability and reproducibility of electrical conductivity.     

橡胶微观结构对NBR硫化加工特性的影响

研究了丁腈橡胶(NBR)微观结构对NBR及NBR/炭黑混炼胶硫化加工性能的影响.研究表明:丙烯腈含量增加,分子极性增加,物理交联密度增加,致使焦烧时间缩短,正硫化时间先增长后缩短,提高了胶料的加工性能,硫化速度先增加后减小.加入炭黑后,对低丙烯腈含量的NBR1846的硫化转矩影响最大,减小了因丙烯腈含量造成的流变性能的变化,缩短了硫化时间,提高了硫化转矩和硫化程度,但炭黑对NBR的硫化速度影响不明显.     

橡胶制品中炭黑含量的测定

炭黑是橡胶工业不可缺少的原料,其用量仅次于生胶,是一种最有效的、被广泛应用的补强剂。炭黑能改进硫化胶的性能,提高胶料的硬度、模量、断裂能量、抗张强度、抗撕裂、耐疲劳和耐磨耗性能。炭黑的另外一大作用是有效降低橡胶制品的成本,特别是用在硅橡胶、氟橡胶和丙烯酸酯橡胶等特种橡胶制品中。对后者来说,炭黑用量越多越好,但过量的炭黑无助于增强、补强效果,反而影响制品的光洁度和拉伸性能,增加制品的加工难度,因此合理的炭黑用量是橡胶工业的研究课题。如何准确测定制品中炭黑的含量呢芽本文主要介绍橡胶制品中炭黑含量的测定方法。…     

Modeling the vulcanization reaction of silicone rubber

Characterization of the vulcanization process of silicone rubber was achieved through the modeling of dynamic DSC tests. The Kissinger equation and the Kamal‐Sourour model were used to determine kinetic parameters that fit the experimental data. The technique allows for the determination of the activation energy through Kissinger's model, which is then used to mathematically determine the other five parameters for the Kamal‐Sourour model. This novel technique finds a physically meaningful activation energy. The method generates a single set of parameters that accurately models all scanning rates tested (1, 2.5, 5, and 10 K/min). Five formulations of liquid silicone rubber as well as one solid silicone rubber were tested and modeled. For each material, the models generated fitting parameters that were in agreement with the dynamic DSC scans. The models were used to compare the processing of the liquid and solid silicone rubber. The characterization of both materials demonstrates the lower processing time, temperatures, and energy consumption when processing liquid silicone rubber, as compared to processing of hard silicone rubber. POLYM. ENG. SCI., 47:675–683, 2007. © 2007 Society of Plastics Engineers.     

新型氟橡胶硫化剂

近年来,氟橡胶以其优异的耐热、耐油、耐溶剂、耐强氧化剂、阻燃等特性,以及良好的加工性能,越来越受到人们的重视,氟橡胶作为一种不可替代的高性能弹性体材料,不仅在需求上有了大幅度增加,而且其应用范围也正在不断扩大。氟橡胶的加工助剂也成为生产发展的一个重要环节,不少人