木质素作为偶联剂在橡胶中的作用

对阔叶林木质素粉末与硅烷偶联剂分别等量加入天然橡胶中的性能及用吸收硫后的木质素废液,对丁腈橡胶、丁苯橡胶、三元乙丙橡胶不同添加量的试验进行了研究。结果表明：木质素粉末具有类似硅烷偶联剂KH-590的作用,吸收硫后的木质素废液添加到橡胶中依然是一种良好的且剂。     

超细木质素粉末的制备及其在橡胶中的应用

选择制备超细木质素粉末的工艺条件，制备细粒子木质素作为偶联剂用于橡胶，对NR、NBR有较好的补强作用。与硅烷偶联剂KH－590的比较表明：细粒子木质素在橡胶中性能优于KH－590，同时还具有提高橡胶耐磨性能的作用。     

木质素的改性及其在橡胶中的应用研究进展

介绍木质素的改性及其在橡胶中的应用研究进展。指出常用的胶乳共沉法、湿混工艺、动态热处理、预分散改性和化学改性技术等只能改善木质素在橡胶基体中的分散性,不能明显提高木质素的疏水性,研究简便环保的方法提高木质素的疏水性以提高其与非极性橡胶之间的相容性将是今后研究的重点和难点。木质素在橡胶中还有用作偶联剂、防老剂和阻燃剂的潜质。未来橡胶补强填料的发展方向应是廉价、易得、轻巧和可再生,具有上述优点的木质素作为橡胶填料的产业化前景明朗广阔。     

酶解木质素的研究进展及其在橡胶工业中的应用

酶解木质素是利用酶解生物质原料制备能源酒精的残渣中分离得到的木质素,具有纯度高、化学活性强等特点。介绍了酶解木质素的制备及其研究进展,并着重阐述了酶解木质素及其衍生物在橡胶工业中的应用情况。     

木质素-碳酸钙复合物的制备及其在丁腈橡胶和丁苯橡胶中的应用研究

以木质素和碳酸钙为原料,在球磨机上以一定的转速并按照一定的配比混合湿法球磨制备了木质素-碳酸钙(Lignin-Ca CO3)复合物,并将其分别用于丁腈橡胶(NBR)和丁苯橡胶(SBR)中,共混制备了丁腈橡胶/木质素-碳酸钙(NBR/Lignin-Ca CO3)和丁苯橡胶/木质素-碳酸钙(SBR/Lignin-Ca CO3)复合材料。考察了木质素-碳酸钙(Lignin-Ca CO3)复合物的配比、木质素-碳酸钙(Lignin-Ca CO3)复合材料的硫化剂用量、硫化温度对橡胶复合材料力学性能的影响。在此基础上,选定了一个适宜的复合填料组成比例,研究了不同填料份数对橡胶复合材料的力学性能的影响。研究结果表明:丁腈橡胶/木质素-碳酸钙复合材料中当填料份数为60时,木质素与碳酸钙之间的配比为30/10,硫化剂用量为2.5 phr,硫化温度为170℃其综合性能最好,其中拉伸强度、断裂伸长率、300%定伸应力和硬度分别为18.7 MPa、774%、3.8 MPa和74 HA;丁苯橡胶/木质素-碳酸钙复合材料当填料份数为40时,当木质素与碳酸钙之间的比例为20/20,硫化剂用量为1.5 phr,硫化温度为160℃其综合性能最好,其中拉伸强度、断裂伸长率、300%定伸应力和硬度分别为8.4 MPa、706%、1.1 MPa和48 HA。     

木质素在橡胶胶料中的应用

木质素生物聚合物是木材加工废料的一个主要成分,焚化是最常用的方法。最近,研究了木质素在材料循环利用技术方面的应用,有人研究了某些类型木质素在制备交联树脂方面的应用,在许多论文中还研究了木质素在橡胶并用胶和热塑性塑料改性方面的应用。在并用胶和热塑性塑料中填加木质素对于材料的热稳定性有积极的作用。     

纤维素在橡胶复合材料中的应用进展

纤维素经过处理后得到微米/纳米尺寸结构、高结晶度的纤维素,是可再生橡胶补强填料。本文系统介绍了微米、纳米纤维素晶体的制备方法,综述了微米、纳米纤维素晶体及不同改性材料改性后增强橡胶制备复合材料的进展,最后对纤维素增强橡胶复合材料研究的方向进行了展望。     

断裂力学方法在橡胶复合材料疲劳研究中的应用

综述断裂力学方法在橡胶复合材料中的应用现状,着重介绍了撕裂能理论在预测疲劳裂纹增长速率以及预报疲劳寿命方面的应用。     

Utilization of lignins in rubber compounding

Lignin in the form of lignosulfonate containing about 33% moisture was found to be dispersible in natural rubber by dry mixing. Properties such as tear resistance, abrasion resistance, flex crack resistance, and crack growth resistance improved upon addition of lignin, irrespective of the nature of filler added. This lignin was found to have negative effects on modulus, tensile strenght, resilience, heat buildup, and compression set, which showed, however, remarkable improvement upon aging.     

钢丝帘布中胶料回收方式的运用

钢丝帘布制成的胎体和带束层,作为全钢子午线轮胎的主要固定形状和承受冲击部件,在全钢轮胎生产企业中被制造使用。在其生产过程中会造成大量钢丝帘布报废,钢丝帘布因其是由按要求排列的钢丝和胶料通过压延机复合在一起的制品,无法直接回收利用,往往是直接卖给回收商,造成胶料成本的浪费。本论文主要针对报废钢丝帘布中胶料回收问题,通过胶料剥离装置、报废帘布储运小车、回收胶料储运装置及整体流程进行设计,对钢丝帘布中的胶料进行高效回收,降低生产成本。     

橡胶活性剂FTY在轮胎和内胎配方中的应用

研究橡胶活性剂FTY在内胎胶和斜交轮胎胎侧胶配方中的应用. 结果表明,在胎侧胶和内胎胶配方中使用橡胶活性剂FTY 50%替代间接法氧化锌,对胶料硫化特性、硫化胶物理性能无不利影响,但材料成本却远远低于间接法氧化锌,经济效益明显.     

The methanogenic toxicity of wastewater lignins and lignin related compounds

Lignin derivatives are major components of wastewater streams generated in the chemical processing of wood. The objective of this study was to evaluate the inhibitory effect of various lignins isolated from forest industry wastewaters, and selected lignin model compounds, on methanogenic bacteria. The methanogenic inhibition was determined at 30°C in standard toxicity assays, utilizing anaerobic granular sludge as inoculum. The wastewater lignins differed considerably in their inhibitory activity. Some lignin samples were nontoxic, whereas others caused 50% inhibition at concentrations ranging from 3320 to 5950 mg COD dm^?3. Experiments with ultrafiltered lignins revealed that the toxicity of the inhibitory lignin samples originated from the low molecular weight fraction. In additional studies with low molecular weight lignin model compounds, it was observed that the inhibitory activity of these compounds was related to the functional groups on the aromatic ring. Compounds with aldehyde groups or apolar substituents were highly toxic, whereas those with carboxylic groups only caused significant inhibition at high concentrations. These results indicate that low molecular weight lignin derivatives in forest industry wastewaters are potential inhibitors of anaerobic treatment systems.     

Sustainable EPM rubber compounds

ABSTRACT

Two important aspects that should be considered when designing new, sustainable rubber products are the bio-based character of the rubber compound ingredients and the recyclability of the vulcanized rubber product. In this work, both are addressed by compounding a thermoreversible cross-linked EPM rubber with pyrolysis carbon black and squalane as sustainable filler and plasticizer, respectively. The resulting rubber product is fully reprocessable in the melt and it displays material properties comparable to those of compounds with conventional additives with high retention of the material properties upon reprocessing.     

Thermal diffusivity of rubber compounds

Abstract

During the vulcanisation process, rubber compounds are heated to temperatures of ～200°C and then cooled. An increase in temperature occurs in rubber tyres during use as a result of heat produced by repeated deformation. This temperature increase can be so high that it can cause tyre destruction. From this point of view, knowledge of thermal diffusivity data of rubber compounds and reinforced rubber is very important. Despite thermal diffusivity being a crucial value, which determines the rate of heating or cooling of solid bodies, only limited data of this kind are available in the literature for elastomers. A new method, developed especially for determining the thermal diffusivity of thick fibre composite materials and reinforced rubber, has been used to measure the thermal diffusivity of rubber compounds. Both the content and the type of rubber and carbon black determine the thermal diffusivity. The content of other components, however, has a very limited influence on this parameter.     

Multilayer coextrusion of rubber compounds

This research work presents the first continuous multilayer coextrusion system for high viscosity elastomeric materials. Three unvulcanized rubber materials were chosen to validate the system: two butyl rubbers and a polyisoprene. The elastomers were characterized under oscillatory shear and the results used to perform computational flow simulations to investigate the effect of geometry on the flow path and flow rate. Successful extrudates of 8 and 32 layers were extruded at two different throughput rates for rheologically matched and rheologically mismatched material pairs. The results show good layering performance for both systems with little existence of viscous encapsulation and acceptable pressure drops. Computational and experimental results both show a nonuniform layer thickness distribution due to the geometric design of the layer multiplier extrusion dies, which were designed to minimize pressure drop in the system. This nonuniformity decreases with increasing number of layers. POLYM. ENG. SCI., 55:1520–1527, 2015. © 2015 Society of Plastics Engineers     

Specific heats of rubber compounds

The specific heats of rubber compounds are very important not only for the thermodynamic calculations in various rubber processings; mixing, extrusion, calendering, and vulcanization, etc., but also for the service life of the final products under repeated stressing conditions. In this study, the specific heats of various compounding ingredients and their compounds for tires were determined using a differential scanning calorimeter (DSC) in the temperature range from 45 to 95°C. The determined specific heats, C_p, were compared with the previous published results for natural rubber (NR), styrene–butadiene rubber (SBR), polybutadiene rubber (BR), and isoprene–isobutyl rubber (IIR). The effects of carbon black loading and vulcanization on the specific heats were investigated. The measured specific heats of the compounds were compared with the calculated values based on the fractional summation of the specific heat of each compounding ingredient. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1513–1522, 1999     

Viscoelastic characterization of rubber compounds

The viscoelastic properties of gum rubbers and the properties of corresponding compounds are discussed. Representative examples are given to illustrate the important influence of gum rubber on the compound properties. A method for evaluating strain amplification and strain-rate amplification is proposed. Examples are given to show the characterization of compounds with respect to the variation in gum rubbers and carbon black grades. The unique characteristics of compounds which are not observed in gum rubbers are also discussed.     

Studies of sulfur behavior in rubber compounds

The influence of temperature and storage time of polymeric sulfur from different producers on its behavior in rubber compounds was studied. Also, the influence of activation by neutron irradiation on a quantity of an insoluble fraction in polymeric sulfur was investigated. To better understand the reason of the small difference in properties of tested polymeric sulfur, its topological structures were evaluated using a thermomechanical method. It was confirmed by a previous conclusion that these kinds of polymeric sulfur have very similar topological structure, and as a result, their behavior in rubber compounds should be practically the same. Studying the reason of blooming in the mineral sulfur it was found that at normal storage conditions, sublimation and oxidative degradation of soluble sulfur could be negligible. For these measurements radioisotopic methods were used. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1531–1536, 1998