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尼龙6/凹凸棒土纳米级复合材料的合成 总被引:31,自引:0,他引:31
对凹凸棒土进行纯化和活化后,用原位聚合方法合成了纳米级尼龙6/凹凸棒土复合材料,对复合材料进行的测试表明,复合材料的力学性能比尼龙6高,但制得的聚合物的相对分子质量偏低。 相似文献
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基于流程模拟软件Aspen Polymer Plus建立了己内酰胺水解聚合生产尼龙6的两段式工艺过程模型,利用该模型对某厂2万吨/年两段式生产工艺进行模拟,各聚合阶段内己内酰胺、环状二聚体含量、聚合物分子量,以及各聚合阶段温度分布和两聚合塔塔顶出水量等结果均与工业值吻合良好,模型可靠。在此基础上,进一步模拟考察了聚合反应过程中进料水含量、分子量调节剂含量、各聚合阶段温度和各聚合塔压力等因素对己内酰胺转化率、环状二聚体生成以及聚合产品分子量的影响,并进行了参数灵敏性分析。结果表明:较低的进料水含量、降低反应温度和前聚塔压力及提高后聚塔的真空度均有利于降低聚合产品中环状二聚体的含量;两个聚合塔下半段的温度变化对环状二聚体产生有显著影响,提高后聚塔真空度可显著提高聚合物分子量。以尼龙6连续聚合过程的环状二聚体含量调控为目标,在优化的操作条件下,尼龙6聚合物中环状二聚体的含量可降低约16%。 相似文献
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为加深对聚己二酰己二胺(尼龙66)缩聚过程的理解,指导尼龙66生产过程的优化和新工艺开发,本研究基于聚合反应特性以及反应器流体力学特征,耦合聚合反应动力学模型、水-聚合物体系的汽液平衡模型以及传质模型,建立了尼龙66连续缩聚过程管式反应器和后缩聚反应器的数学模型,实现了尼龙66连续聚合过程的模拟。聚合物分子量及水含量的模拟值符合工业生产数据,验证了模型的可靠性,模拟分析了聚合工艺参数对聚合物分子量及水含量的影响,结果表明减少醋酸含量、提高反应器温度、降低管式反应器和后缩聚反应器压力均有利于快速提升聚合物分子量。较优的工艺条件为后缩聚器温度280~285℃,卧管式反应器压力1.600~1.750MPa。建立的模型准确性好,可用于考察工艺参数的影响,指导工业应用。 相似文献
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双苯环长碳链半芳香尼龙的合成与表征 总被引:7,自引:0,他引:7
利用本体聚合方法,通过4,4′-二羧基联苯醚和4,4′-二羧基联苯砜分别与十二碳二胺的缩聚反应,制备了两种新型的半芳香尼龙:聚联苯砜二甲酰十二碳二胺(PA12-S)和聚联苯醚二甲酰十二碳二胺(PA12-0)。研究了反应时间和反应温度对聚合物摩尔质量的影响,并以IR、^1H NMR表征了两种聚合物的结构;利用DSC、TG研究了聚合物的热性能。结果表明:在一定范围内,升高反应温度和增加反应时间会提高产物的摩尔质量,两种半芳香尼龙具有较高的玻璃化转变温度,热分解温度比脂肪族尼龙高约20℃,同时两种半芳香尼龙均具有良好的耐溶剂性能。 相似文献
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为了在碳纤维生产线上配备碳纤维/尼龙6复合材料在线生产装置,探究了一种通过纤维活化原位浸渍聚合法在碳纤维表面合成尼龙6的方法,即先在碳纤维表面包覆一层活化剂TDI(2,4-甲苯二异氰酸酯),将纤维活化,再将活化后的纤维通过预先对己内酰胺与引发剂氢氧化钠体系除水而获得的单体阴离子熔体中,通过单体阴离子扩散聚合在纤维表面形成一层尼龙6。研究表明,采用该纤维活化原位浸渍聚合方法可以成功地在碳纤维表面形成一层尼龙6树脂,但聚合温度对尼龙6的转化率、熔融结晶行为和分子量影响较大,过量的活化剂对尼龙6的转化率也存在不利影响,如果改进活化剂配比,将会提高聚合物的转化率。最后通过红外、电镜扫描(SEM)对材料的官能团分布和微观形貌进行了研究。 相似文献
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以质量分数52.8%的尼龙66盐液为原料,采用一步法连续聚合熔体直纺工艺生产高强超低热收缩尼龙66纤维,探讨了聚合物相对黏度、纺丝温度、上油率、拉伸倍数、热定型温度、松弛比等工艺参数对生产及产品质量的影响.结果表明:较佳的生产工艺条件为尼龙66聚合物相对黏度77~79、纺丝温度298~302℃ 、上油率(0.80±0.... 相似文献
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以Ziegler-Natta催化剂TiCl4/Al(i-Bu)3为催化体系,己烯、辛烯、癸烯和十二烯四种长链α-烯烃为聚合单体,制备得到超高相对分子质量聚烯烃减阻剂。考察了聚合反应条件对聚合物相对分子质量的影响,以及单体侧链长度对聚合物结晶性和减阻性能的影响。结果表明:最佳聚合条件为,主催化剂TiCl4浓度为5.2×10-4mol/L,聚合单体与环己烷体积比为1:1,反应时间至少为1440mins(24h), 此 时聚合产物重均相对分子质量达到3.50×106;通过13C NMR对聚合物进行分子结构表征,证明聚合完全且为目标产物;DSC曲线和XRD谱图表明,随着聚烯烃的侧链长度增加,聚合物结晶性增强, 影 响聚合物减阻剂溶解性。采用旋转圆盘测试方法表征了聚合物减阻率结果表明,在相同相对分子质量条件下,随着聚合物的侧链长度增加,减阻率明显提高。 相似文献
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<正> 60年代初中国科学院化学研究所研究出了一种新的合成工艺技术,用浇涛的方法在尼龙聚合物的熔点以下制出大型尼龙制品。它是用尼龙6原料己内酰胺单体HN(CH_2) _5CO,加上碱催化物质直接注入预热的模具中聚合成型的。用这种方法制成的尼龙,称为铸塑尼龙或碱聚合尼 相似文献
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采用原位聚合反应制备MC尼龙/纳米CaSO4复合材料并对其性能、形貌和结晶形态进行了分析。分析结果表明:复合材料中纳米CaSO4达到了纳米级分散,起到同时增强增韧的作用,复合材料拉伸强度比MC尼龙提高17.4%;弯曲模量提高26.9%;冲击强度提高16.7%。纳米CaSO4的引入没有改变尼龙6的结晶形态;修饰后的纳米CaSO4有利于在MC尼龙中均匀分散。 相似文献
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George C. Jacob J. Michael Starbuck John F. Fellers Srdan Simunovic Raymond G. Boeman 《应用聚合物科学杂志》2006,101(3):1477-1486
The ACC (Automotive Composite Consortium) is interested in investigating the use of random chopped fiber reinforced composites as crash energy absorbers primarily because of the low costs involved in their manufacture thus making them cost effective for automotive applications. Although many scientists have investigated the energy absorption characteristics in various continuous fiber reinforced composite materials and their dependence on strain rate, there is very little literature available on the energy absorption and crushing characteristics of random chopped fiber reinforced composite materials and their strain rate dependence. Therefore, the primary goal was to determine the crashworthiness of various random chopped carbon fiber composite material systems. To meet this goal, first an experimental set up was developed for discerning the deformation behavior and damage mechanisms that occur during the progressive crushing of composite materials. The three different random chopped carbon reinforced epoxy composite material systems studied were P4, HexMC, and CCS100. Quasi‐static progressive crush tests were then performed on these random chopped carbon fiber composite plates to determine their crashworthiness. In addition, an attempt was made to investigate and characterize the strain rate effects on the energy absorption of a random chopped carbon fiber P4 composite. The specific energy absorption was found to increase with increasing loading rate from 15.2 to 762 cm/min. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1477–1486, 2006 相似文献
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Chopped carbon fibers were introduced into the SiC/C suspensions to enhance the mechanical behaviors of reaction bonded silicon carbide ceramics. The effects of fiber fraction on the flexural strength and fracture toughness were investigated. No preferred fiber orientation was observed on the fracture surface of the green body. This implies a homogeneous dispersion of chopped fiber in the composite. XRD analysis indicates a complete siliconization of both carbon particles and carbon fiber during liquid silicon infiltration. The flexural strength and fracture toughness increase with chopped fiber ranging from 10 vol.% to 30 vol.%. This improvement derives from the fiber pullout, fiber debonding as well as crack deflection. The consequent decline at fiber fraction of 40 vol.% is resulted from the siliconization of chopped fiber and the increase of residual silicon. 相似文献
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《Polymer Composites》2017,38(12):2798-2805
The thermoplastic matrix composites have gained great importance in last three decades. The chopped basalt fiber (mineral fiber) is considered to be a good fiber due to excellent properties as potential reinforcement of composite materials. In this work, composites of chopped basalt fiber (6 mm) with thermoplastic material Nylon‐6 (Polyamide‐6) were prepared and its mechanical and morphological properties were evaluated for automobile applications. The melt blending was carried out in corotating twin‐screw extruder and injection‐molded test samples were prepared for the analysis. The test samples of composite without coupling agent prepared by varying the loading of basalt fiber content of 5%, 10%, 15%, 20%, and 25% by weight and with coupling agent composite loading of Nylon‐6 and basalt fiber content were kept constant and the coupling agent (PE‐g‐MA) loading were changed as 1, 2, 3, 4, and 5 phr. The Mechanical and SEM properties were evaluated. From the test results, it was observed that the mechanical properties were improved with increasing coupling agent ratio. SEM images show good dispersion and adhesion of matrix and reinforcement. POLYM. COMPOS., 38:2798–2805, 2017. © 2015 Society of Plastics Engineers 相似文献
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玻纤、粉煤灰增强MC尼龙复合材料的研究 总被引:1,自引:0,他引:1
利用铸型尼龙(MC尼龙)静态浇铸的原理,通过阴离子聚合制得了玻纤、粉煤灰增强MC尼龙。研究了不同玻纤和粉煤灰质量分数对复合材料性能的影响。结果表明,用这种方法制得的玻纤、粉煤灰增强MC尼龙的机械性能较普通MC尼龙有较大幅度提高,纤维在基体中的分散性好,与基体的粘接性也相当好;加入30%玻璃纤维和10%粉煤灰可使复合材料的拉伸强度提高13.8%、弯曲强度提高32.8%、弯曲弹性模量提高110%、无缺口冲击韧性提高442%、而硬度提高49.6%。 相似文献