共查询到20条相似文献,搜索用时 15 毫秒
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在胶乳状态下制得不同溴含量的溴化天然橡胶产物,并采用傅里叶红外光谱和1H NMR核磁共振测试技术对胶乳法溴化天然橡胶(BNR)的结构进行了表征,用扫描电子显微镜对BNR的形貌进行了观察,考察了不同溴含量BNR的溶解性能和氮含量。红外光谱分析表明,天然胶乳溴化反应时发生了溴化取代和加成反应;1H NMR分析结果则证实存在C=C双键加成和亚甲基、甲基的溴化取代。 随着溴含量的增加,BNR产物逐渐变得硬而脆,最终呈粉末状,且粒径减小。 同一溴化天然橡胶产物在不同溶剂中的溶解能力由小到大依次为:四氯化碳、苯<甲苯、二甲苯<四氢呋喃<三氯甲烷<环己酮;在同一有机溶剂中BNR的溶解性能则随着溴含量的增加而增大。 BNR产物的含氮量随着溴含量的增加而减小,当溴含量为42%时,氮含量减小至0.10%。 相似文献
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Ground rubber powder (GRP) with three different sizes was incorporated into nature rubber matrix with different loading. Cure characteristics, swelling behaviour, crosslink density, tensile fractured surface, and mechanical properties have been studied. Based on the cure characteristics, it is evident that the processability of the rubber compounds has not changed obviously with the different GRP loading. The introduction of GRP in virgin rubber leads to the increase in swelling degree and the decrease in crosslink density. Tensile strength, hardness and abrasion resistant deteriorate with the increase of GRP loading, but the tear resistance gets better. If the ground rubber particles are smaller, the properties are more similar to the virgin rubber. Because of the phase separation of the GRP and matrix, the properties get worse with the bigger ground rubber powder. 相似文献
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Jareerat Samran Pranee Phinyocheep Philippe Daniel Daniel Derouet Jean-Yves Buzare 《Macromolecular Symposia》2004,216(1):131-144
The diimide hydrogenation of natural rubber (NR) was studied by using p-toluenesulfonylhydrazide (TSH) as a diimide-releasing agent. The microstructure and the percentage of hydrogenation were studied by Raman, 1H-NMR and 13C-NMR spectroscopic techniques. Quantitative measurements on fraction of hydrogenated part gave the results in good agreement by using these techniques. The results indicated that percent hydrogenation increased with increasing of reaction time and about 80-85 % hydrogenation was achieved when a two-fold excess of TSH was used. The vibrational characteristic of C=C bond of NR is strongly Raman active and noted at 1663 cm−1. The decrease of this signal was clearly observed during the progress of hydrogenation but the vibrational frequency of the cis and trans structures of the trisubstituted olefin unit of NR can not be differentiated by this technique. While 1H- and 13C-NMR analysis showed that cis-trans isomerization of carbon-carbon unsaturation of NR occurred during hydrogenation. 相似文献
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胶粉/热塑性塑料共混材料的研究 总被引:3,自引:1,他引:2
以胶粉及通用塑料PP和LLDPE为原料,研究了原料种类、相容剂等对胶粉/热塑性塑料共混材料性能的影响,制得了性能较好的共混材料。通过热分析和扫描电镜对制得的共混材料进行分析表征,表明胶粉和LLDPE有较好的相容性及较强的结合力。 相似文献
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Some synergistic effects of antioxidants in natural rubber were investigated considering results obtained by differencial
scanning calorimetry (DSC). Rubber formulations were obtained with mixtures of diaminic(DPPD, IPPD, HPPD) and monoaminic (ADPA,
PBN) stabilizers and evaluated. The samples containing the mixture diamine/ADPA stabilizers showed synergistic effects while,
for those containing diamine/PBN, no effect was observed. Additionally, the diffusion constants determined by use of vulcanized
rubber disks confirmed the molar mass dependence of the stabilizer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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用FTIR研究环氧化天然橡胶的热老化 总被引:8,自引:0,他引:8
与天然橡胶(NR)相比,环氧化天然橡胶(ENR)具有良好的耐油性和气密性[1,2],并由于环氧基团而有一定的极性,同其它高聚物的相容性较好.通过环氧基团的二次反应,ENR分子链可接上其它的功能团,满足一些特殊的用途[3,4].对于ENR的力学性能、共... 相似文献
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天然橡胶分子链双键中引入环氧基对其性能的影响 总被引:1,自引:0,他引:1
天然橡胶在乳液状态下与过氧乙酸反应,在主分子链双键中引入环氧基团,可显著提高分子极性,但其高强伸性能基本保持不变;玻璃化温度上升,冲击弹性下降,耐油性、气密性、粘合性显著改善。 相似文献
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Domenico Acierno Ireneo Ciccarelli Vittorio Romano Pietro Russo 《Macromolecular Symposia》2007,247(1):244-251
Summary : Reuse and recycling of tires at the end of their useful life is an environmental challenge owing to the huge volumes discarded all over the world. This paper tries to give a scientific contribution toward the mechanical recycling of elastomers derived from pre treatment of tires to produce anti-shock tiles and heat-insulating panels for civil applications. Thermal and mechanical results herein reported satisfactorily justify the interest devoted by now to this topic. 相似文献
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