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高全同聚丁烯-1树脂是目前先进的高分子材料之一。采用液相本体法合成了聚丁烯-1,考察了聚合条件对聚丁烯-1性能的影响,主要考察了聚合反应活性、全同含量和相对分子质量及其分布的影响因素,并指出了高全同聚丁烯-1树脂的发展前景。 相似文献
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江镇海 《精细与专用化学品》1997,(18)
聚丁烯-1是以丁烯-1为原料,在齐格勒-纳塔陛化剂存在下采用低压淤浆法聚合而制得的。它是一种半结晶聚烯烃热塑性树脂。聚丁烯-1树脂具有良好的机械性能,突出的耐环境应力开裂性、耐低温流动性和耐蠕变性、耐热性、耐化学腐蚀性,具有抗磨性、可挠曲性和高填料填充性,可用于生产管道、薄膜、板材和各种容器等。 相似文献
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采用硅烷、铝酸酯和钛酸酯偶联剂对碳酸钙进行表面处理,并以聚丁烯–1为基体制备了聚丁烯–1/碳酸钙复合材料,研究了这3种偶联剂对复合材料性能的影响。结果表明,钛酸酯和铝酸酯偶联剂对碳酸钙改性的效果最好,其中铝酸酯偶联剂改性的碳酸钙接触角最大,对复合材料的增韧效果最明显,当铝酸酯偶联剂改性的用量为碳酸钙的1.5%时,改性后的碳酸钙接触角可达162.4°,相应的复合材料缺口冲击强度由未改性时的21.5 k J/m2提高至31.7 k J/m2。对铝酸酯偶联剂改性碳酸钙填充的复合材料的结晶性能及微观结构进行了分析与表征,发现铝酸酯偶联剂改性碳酸钙能够提高聚丁烯–1的结晶度,在基体内形成紧密堆积的细小球晶;铝酸酯偶联剂改性碳酸钙在聚丁烯–1中的分散性较佳,无明显团聚现象,与聚丁烯–1界面结合能力强,能够吸收形变功,提高复合材料的韧性。 相似文献
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采用双螺杆挤出机熔融制备了聚丁烯–1(PB-1)/滑石粉复合材料,研究了滑石粉含量对PB-1熔融及结晶行为的影响。结果表明,滑石粉显著促进了PB-1的结晶过程,其成核能力在滑石粉质量分数为1%时最佳。非等温结晶动力学研究表明,在滑石粉的实验用量范围内(1%~10%),要达到相同的结晶度,PB-1/滑石粉复合材料的完成温度明显高于纯PB-1的完成温度。当滑石粉质量分数为1%~5%时,要达到相同的结晶度,PB-1/滑石粉所需的时间明显比纯PB-1短;当用量为7%时稍短;当用量为10%时又稍长。但滑石粉不影响PB-1的依热成核方式和三维生长机制。偏光显微镜结果表明滑石粉对PB-1的异相成核作用显著。广角X射线衍射研究表明滑石粉阻碍了PB-1由晶型Ⅱ向晶型Ⅰ的转变过程,使晶型转变变缓。 相似文献
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A program was developed that yields the number of chain scission and crosslinking events representing the best fit of a simulated molar mass distribution to a molar mass distribution determined by size exclusion chromatography. The program was applied to molar mass distributions of samples taken from pressure-tested pipes of an unstabilized medium-density polyethylene. Good fits were obtained after various exposure times at different temperatures and at different positions in the pipe wall. The ratio of the number of chain scission to crosslinking events generally decreased with increasing exposure time and with decreasing accessibility to oxygen in the pipe wall. Correction for long-chain branching effects led to significant changes in the optimum chain scission and crosslinking values obtained. The broad and asymmetric shape of the molar mass distributions, typical of degraded material from originally stabilized medium-density pipes, was shown to arise from a combination of a uniformly degraded and a nondegraded component. The program was also successfully applied to the molar mass distribution of a sample taken from a degraded commercial polybutylene-1 pipe. 相似文献
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N. Sotirhos Chi-Tang Ho Stephen S. Chang 《European Journal of Lipid Science and Technology》1986,88(2):45-48
A high performance liquid chromatographic (HPLC) method has been developed to analyze oxidative and polymerized decomposition products in commercial vegetable oils and heated fats. The oil was passed through a SEP-PAK where the minor constituents were concentrated. The SEP-PAK was eluted with hexane-ether 1:1 (v/v), and 2-propanol. The first eluate contained unsaponifiables and neutral lipids, and the second eluate contained the more polar oxidative and polymerized decomposition products. The second eluate was analyzed by normal phase HPLC. Five commercial vegetable oils were analyzed, and similarities and differences were observed. Four soybean oil samples from different manufacturers also showed differences. Soybean oil heated at 185°C was collected periodically and analyzed. As the heating time increased, the oxidation and polymerization products also increased. Used frying fat samples from a commercial fried chicken manufacturer were analyzed. The frying oil quality reached an equilibrium during three days of operation, because the oil lost in frying was replenished daily with fresh shortening. 相似文献
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David L. Trumbo 《Polymer Bulletin》1996,37(1):75-80
Summary The title monomer was synthesized and polymerized via free radical initiation. The high field 1H- and 13C-NMR spectra were recorded and analyzed. Many resonances displayed multiplicities indicating a sensitivity to polymer stereochemistry but, in most cases, the resolution was insufficient for any reasonable interpretations to be made. The resonances that were well enough resolved for relatively accurate measurements to be made were analyzed in terms of polymer stereochemistry. The analysis suggests that poly(3-vinyl-1-methyl-indole) is an atactic polymer. 相似文献
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目的分析钙蛋白酶抑制蛋白(Calpastatin,CAST)基因多态性与西门塔尔杂交牛胴体和肉质性状的相关性。方法选取95头西门塔尔杂交牛,采用限制性片段长度多态性聚合酶链反应(Restriction fragment length polymor-phism-polymerase chain reaction,RFLP-PCR)对CAST基因外显子1(Exon1)和外显子5(Exon5)区域的片段的多态性进行检测,并对突变位点与西门塔尔肉牛胴体和肉质性状的相关性进行分析。结果在所分析的片段中,仅引物4扩增的片段(Exon1)存在一个G→C碱基的置换突变(E1 256 g﹥c),为同义突变;该突变位点为RasⅠ酶的自然酶切位点,酶切后存在GG、GC和CC 3种基因型,CC基因型与西门塔尔牛的净肉率性状显著相关(P﹤0.05),而对其他胴体和肉质性状无显著影响。结论 CAST基因Exon1处存在的突变位点与西门塔尔肉牛的净肉率显著相关,因此该位点将有助于筛选与牛肉质相关的辅助选择标记,该基因将为鉴定与肉质相关的功能基因提供参考。 相似文献
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对合成溴氰菊酯的重要中间体(1R)-Cis-二溴菊酸的合成工艺及其最新的研究进展进行介绍。分析了这些合成工艺的优缺点。展望了(1R)-Cis-二溴菊酸发展前景。 相似文献
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采用逐步聚合方法制备了新型特种工程塑料含二氮杂萘酮结构的聚芳醚砜酮[PPESK(1/1)]和聚芳醚砜(PPES).利用热失重(TGA)分析仪,氮气氛围中,多重加热扫描速率下的不定温法对PPESK(1/1)及PPES进行热分解动力学研究.根据Satava法得出,聚合物PPESK(1/1)分解反应机理为随机成核和随后生长,反应级数n=1;而聚合物PPES的热分解反应机理为相界面反应模式,反应级数n=2.同时采用经典动力学方程Friedman、Kissinger-Akahira-Sunose(KAS)及Ozawa方程计算了热分解动力学参数(Ea,lnZ).重点考察升温速率、不同酮/砜比对PPESK(1/1)热稳定性影响,并且根据得到的动力学参数推测其在高温使用条件下的使用寿命及对热分解反应过程中“动力学补偿效应”(KCE)进行分析. 相似文献