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硼酸、腰果油双改性酚醛树脂的合成及其耐热性研究 总被引:14,自引:0,他引:14
本文通过正交实验讨论了硼酸、腰果油改性酚醛树脂的合成方法。对于树脂的热重分析结果表明此树脂的耐热性优于普通的酚醛树脂。最后本文还确定了较好的改性剂加入量。 相似文献
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采用红外光谱、热重分析方法、扫描电镜等方法,研究了不同加入量液体丁腈橡胶(LNBR)对钼酚醛树脂性能和结构的影响。结果表明,当液体丁腈橡胶的加入量为6phr时,达到最大的冲击强度,随着加入份数继续增加,其冲击强度基本不变;在共混的过程中发生了共聚反应;共混后,耐热性也有所提高;橡胶的空化以及"银纹"的产生是冲击强度增大的原因。 相似文献
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桐油改性酚醛树脂的研究 总被引:19,自引:0,他引:19
通过桐油和本酚在催化剂存在下反应,然后再在碱性催化剂存在下与甲醛反应成功地制得了一种桐油改性甲阶酚醛树脂。利用红外光谱和1H—核磁共振谱等分析技术对这类改性树脂的结构的基本性能进行了表征。用这类桐油改性酚醛树脂代替橡胶改性酚醛树脂作为基作树脂所压制的石棉基汽车刹车片,其摩擦性能显著提高并超过GBn257—86所规定的技术要求,可望用作耐高温摩阻材料。 相似文献
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端羧基丁腈橡胶改性酚醛树脂的性能研究 总被引:2,自引:1,他引:1
采用端羧基丁腈橡胶(CTBN)对酚醛树脂进行改性,研究CTBN用量对改性酚醛树脂力学性能的影响。酚醛树脂的拉伸强度、断裂伸长率随CTBN用量的增大而呈上升趋势,当CTBN用量为10%时,拉伸强度、断裂伸长率达到最大值,并利用扫描电子显微镜(SEM)、傅立叶转换红外光谱(FTIR)和热重法(TGA)对改性前后酚醛树脂的结构和热性能进行分析。结果表明,CTBN与酚醛树脂之间发生了化学反应,并且改性酚醛树脂的热性能有所下降。 相似文献
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采用熔融共混工艺制备了氢化丁腈橡胶(HNBR)/超细全硫化粉末丁腈橡胶(UFPNBR)共混物,研究了共混物相态结构、动态力学性能、力学性能及老化性能,并与HNBR/NBR共混物作了对比。透射电镜观察表明:在HNBR/UFPNBR体系中,HNBR容易形成连续相,UFPNBR为分散相;在HNBR/NBR体系中容易形成双连续相结构。DMA动态力学性能分析表明:2种共混物都只有一个tanδ峰,且相容性较好。HNBR/UFPNBR共混物在玻璃化转变区的tanδ峰值逐渐降低,而HNBR/NBR体系的tanδ峰值先减小后增大。加入适量的UFPNBR能降低HNBR/UFPNBR共混物的压缩永久变形;与常规共混胶相比,HNBR/UFPNBR具有低脆性温度和良好的耐老化性能,但力学性能略低。 相似文献
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顺丁、丁腈橡胶离聚体改性聚氯乙烯研究 总被引:2,自引:0,他引:2
用马来酸酐接枝橡胶和金属离子交联形成离聚体的方法可提高顺丁橡胶(BR)、丁腈橡胶(NBR)、PVC三元共混物的相容性,以交联剂、引发剂、接枝单体为三要素,采用正交试验方法,通过综合评分法,优选了三元离聚体配方,在此基础上用部分硬脂酸锌代替无机氧化锌作离子交联剂,使合金材料获得了满意的性能,与未经改性PVC/BR/NBR三元共混物相比,硬脂酸锌离子交联马来酸酐接枝的三元合金的拉伸强度提高了101%,断裂伸长率增加113%,红外光谱证明了马来酸酐接枝顺丁胶与锌离子的离子交联的存在,且硬脂酸锌的效果优于氧化锌。 相似文献
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考察妥尔油改性酚醛补强树脂SL-2101和腰果油改性酚醛补强树脂SL-2201对全钢载重子午线轮胎三角胶性能的影响。结果表明:与补强树脂SL-2101相比,补强树脂2201对胶料的补强性能好;随着2种补强树脂用量增大,胶料物理性能提高;采用补强树脂SL-2201替代补强树脂SL-2101,需适当调整硫化体系。 相似文献
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The behaviour of styrene butadiene rubber/acrylonitrile butadiene rubber (SBR/NBR) blends in the environment of chlorinated hydrocarbons, such as carbon tetrachloride, chloroform and dichloromethane, in the temperature range 32–52°C has been investigated. Sulphur, dicumyl peroxide and a mixed system consisting of sulphur and peroxide were used as the vulcanising systems for the matrix. The effects of vulcanising agents, blend composition, solvents and temperature on the sorption characteristics were studied. The sulphur-vulcanised systems exhibited the highest solvent uptake and those with dicumyl peroxide as the vulcanising agent the lowest. This difference has been explained on the basis of the nature of cross links established between the polymer chains during vulcanisation. The solvent uptake increased with an increase in SBR content in the blends when carbon tetrachloride was used as the penetrant, whilst it decreased with SBR content when chloroform and dichloromethane were used as the probes. This behaviour has been explained on the basis of the polarity difference of the solvents. For a given blend system, the solvent uptake was maximum when dichloromethane was used as the solvent and minimum when carbon tetrachloride was used. This has been accounted for in terms of the difference in the size of the penetrants. The intrinsic diffusion coefficient, permeation coefficient, cross link density and interaction parameter were estimated from the sorption data. Thermodynamic parameters such as enthalpy and free energy changes were also calculated. These values indicate that the sorption process in the present systems is exothermic and is more spontaneous in sulphur-vulcanised systems. The experimental results, when compared with different theoretical diffusion models, have been found to be closer to Robeson’s and Maxwell’s models. 相似文献
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The comparison properties of polypropylene (PP)/recycled acrylonitrile butadiene rubber (NBRr) blends and polypropylene/virgin acrylonitrile butadiene rubber (NBRv) blends were investigated. The tensile properties such as tensile strength, tensile modulus and elongation at break of PP/NBRv blends are higher than PP/NBRr blends. However, PP/NBRv blends exhibit lower stabilization torque and higher swelling percentage than PP/NBRr blends. Based on SEM, a finer morphology was observed in PP/NBRv blends in comparison with the PP/NBRr blends. The thermal stability of PP/NBRr is better than that of PP/NBRv blends. 相似文献
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