阴离子原位聚合橡胶改性尼龙6的形态结构

采用HDI脲二酮接枝端羟基聚丁二烯液体橡胶(HTPB),再用己内酰胺封端异氰酸酯基团,制得橡胶改性剂,通过阴离子聚合制得液体橡胶改性尼龙(PA)6树脂。分析表明,HDI脲二酮接枝到HTPB的羟基上后被己内酰胺成功封端,进而阴离子聚合生成橡胶改性PA6共聚物。冲击断面分析,当橡胶质量分数高于15%以后,改性PA6树脂表现出明显的韧性断裂,脆断后甲苯刻蚀表明,随着橡胶活化剂含量增加,未参与聚合橡胶含量增加,导致橡胶微相尺寸变大且均匀性下降。在180℃条件下,聚合生成橡胶改性PA6树脂表现为α晶型,橡胶的加入并没有改变PA6的晶型;树脂熔融再速冷结晶后,PA6以亚稳定γ晶型为主,随着橡胶含量的增加,α晶型明显增强,说明橡胶相的存在有助于形成较稳定的α晶型。     

阴离子原位聚合改性尼龙6的研究进展

综述了通过化学方法改性尼龙6的发展概况,简要介绍了用各种弹性体、刚性链段以及共聚单体等,弹性体可采用四氢呋喃聚醚（PTMG）、环氧丙烷聚醚（PPG）、聚乙二醇（PEG）、聚己内酯（PCL）、丁腈橡胶（ATBN）等,刚性链段如聚酰亚胺、N酰化己酰胺末端基芳香族聚酰胺、氯封端聚醚砜等;单体共聚采用己内酯。     

尼龙6的双螺杆反应挤出工艺

介绍了国内尼龙 6的双螺杆反应挤出工艺。通过己内酰胺阴离子型快速聚合 ,直接反应成型制取高性能尼龙 6 ,具有生产连续 ,周期短 ,产品性能好的优点。反应挤出生产的尼龙 6相对粘度可达 4 2～ 5 0 ,拉伸强度、弯曲强度、缺口冲击等性能均优于传统工艺生产的尼龙 6。对双螺杆反应挤出机的工艺要求及特点作了简介。     

尼龙6塑料的国内发展动向

一、引言聚己内酰胺俗称尼龙6(Nylon-6),1938年由德国I.G.Farben公司P.Schlach发明。它是工程塑料中发展最早的品种,目前在产量上居于首位。与其它的工程塑料比较,尼龙6具有很高的机械强度和切性,电气性能良好,耐磨、耐油、耐弱酸、弱碱和一般有机溶剂等。近年来又相继出现了改性的新品种,通过共聚、共混、填充、增强、     

尼龙6树脂及其应用

本文论述了尼龙6树脂的聚合新工艺、加工成型方法和设备特征,探讨了尼龙6塑料品种改性和应用前景,以及尼龙6树脂研制、生产的新技术、新产品的开发动向。     

尼龙6树脂的进展

本文论述了尼龙6树脂的研制、生产情况、新技术、新品种的开发动向。介绍了尼龙6树脂的聚合工艺、成型加工方法和设备特性的新发展。对产品的优良性能和广泛应用及其技术开发水平进行了讨论。并探讨了尼龙6塑料品种改性和扩大应用范围等的发展前景。     

尼龙6/碳纳米管浇铸成型的反应动力学

将改性的多壁羟基碳纳米管分散在熔融的己内酰胺中,一步原位聚合制备MC(单体浇铸)尼龙6/碳纳米管复合材料;采用非等温反应动力学分析方法对尼龙6/多壁碳纳米管浇铸成型的反应过程进行研究.结果表明:随着改性碳纳米管含量的增加,反应活化能及指前因子增加;MC尼龙6及其碳纳米管复合材料成型过程的反应级数都在0.9 ～1之间,可以认为是准一级反应.     

尼龙6/丙烯酸酯橡胶热塑性弹性体非等温结晶动力学

采用动态硫化法制备尼龙6/丙烯酸酯橡胶热塑性弹性体(PA6/ACM TPE),通过差示扫描量热仪研究了PA6和PA6/ACM TPE在5种不同冷却速率下的结晶过程,并分别用Jezirony法、Ozawa法以及Mo法分析了PA6和PA6/ACM TPE的非等温结晶动力学.结果显示,冷却速率越大,PA6和PA6/ACM T...     

尼龙6改性研究

采用经化学改性的芳纶纤维增强尼龙6,并通过红外光谱和电镜分析其界面层,结果表明芳纶纤维经异氰酸酯化及封端稳定处理后,其表面所接技的不稳定基团-NCO转化成稳定的-NHCO-,封端结果较为明显;改性后纤维表面附有接枝物,从而使表面粗糙程度大大增加。用挤出和注塑的方法加工了PA6／Kevlar纤维（KF）复合材料,研究了它的拉伸、弯曲和冲击性能破坏形态。力学性能测试表明了改性尼龙6复合材料的拉伸和弯曲强度得到了改善,但冲击性能略为下降。     

双螺杆反应挤出尼龙-6

双螺杆反应挤出工艺是高分子材料加工的一种新技术，是目前国际上竞相投资的热点。本文将重点介绍作者采用反应挤出新工艺对己内酰胺单体进行双螺杆反应合成高聚物尼龙－６及尼龙－６制品，实现双螺杆挤出机自单体－高聚物－物品的一体化合成工艺过程，突出双螺杆挤出尼龙－６及改性制品固有的特色。     

尼龙 6聚合中几种浓缩液直接回用工艺的对比

对比了国外公司的不同尼龙 6浓缩液直接在己内酰胺聚合中回用的工艺特点 ,国内引进装置采用该工艺的情况及应注意的问题。提出保持聚合进料组成稳定和防止浓缩液析出是成功地采用浓缩液直接在尼龙 6聚合中回用工艺的关键     

离子液体催化废旧尼龙6水解反应

以离子液体1-丁基-3-甲基咪唑溴盐([Bmim]Br)为催化剂,对废旧尼龙6水解反应进行研究。采用FT-IR、TG、GC-MS和UV等对产物进行定性和定量分析。考察反应温度、反应时间、催化剂用量和水用量对尼龙6转化率和产物收率的影响。结果表明,固相产物为未解聚完全的尼龙6,液相产物主要为己内酰胺。硅胶柱层析分离纯化己内酰胺,并利用FT-IR和1H NMR对产物结构进行表征。获得较佳水解条件为:m(尼龙6)∶m(催化剂)∶m(H_2O)=1∶6∶3,反应温度175℃,反应时间9 h,此条件下,尼龙6转化率46.00%,己内酰胺收率为24.56%。     

尼龙6固相聚合模型及计算机模拟研究

根据尼龙6固相聚合反应机理,建立了由可逆化学反应和小分子扩散共间控制的尼龙6固相聚合动力学模型,并确定了其动力学和热力学参数。通过计算机模拟实验表明,聚合反应温度越高,预聚体尺寸越小,预聚体初始相对分子质量越高,越有利于固相增粘反应,有利于固相聚合尼龙6相对分子质量的增加。     

反应注射成型尼龙6的研究进展

介绍了反应注射成型尼龙6（nylon 6-RIM）、增强反应注射成型尼龙6（nylon 6-RRIM）、毡片模塑反应注射成型尼龙6（nylon 6-MMRIM）以及反应注射成型尼龙6嵌段共聚物（NBC-RIM）材料的性能特点以及研究进展。并讨论了nylon 6-RIM材料在各个领域的应用优势和前景。     

Toughened nylon66/nylon6 ternary nanocomposites by elastomers

The elastomer toughening of PA66/PA6 nanocomposites prepared from the organic modified montmorillonite (OMMT) was examined as a means of balancing stiffness/strength versus toughness/ductility. Several different formulations varying in OMMT content were made by mixing of PA6 and OMMT as a master‐batch and then blending it with PA66 and different elastomers in a twin screw extruder. In this sequence, the OMMT layers were well exfoliated in the nylon alloy matrix. The introduction of silicate layers with PA6 induced the appearance of the γ crystal phase in the nanocomposites, which is unstable and seldom appears in PA66 at room temperature and it further affected the morphology and dispersion of rubber phase resulting in much smaller rubber particles. The incorporation of POE‐g‐MA particles toughened the nanocomposites markedly, but the tensile modulus and strength were both reduced. Conversely, the use of OMMT increased the modulus but decreased the fracture toughness. The nanocomposites exhibited balanced stiffness and toughness. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Structure and thermal behaviour of nylon 6 nanocomposites

In this article, nylon 6/clay nanocomposites with 5 wt % clay (NCN5) were prepared by a twin screw extruder. The effects of annealing including solid‐state annealing (170 and 190°C) and melt‐state annealing (240°C) on the polymorphic behavior and thermal property of NCN5 and nylon 6 have been comparatively studied as a function of annealing time using modified differential scanning calorimetry (MDSC) and wide‐angle X‐ray diffraction. It was demonstrated that NCN5 and nylon 6 exhibit a similar polymorphic behavior when they were annealed at 190°C for different time durations. As the annealing temperature was elevated to 240°C, significant differences in thermal behavior and polymorphism between NCN5 and nylon 6 could be found. For example, the α crystal became the absolutely dominating crystalline phase for NCN5 sample independent on the annealing durations, whereas the formation of γ crystal is greatly enhanced in neat nylon 6 with increasing annealing time. Moreover, a small endothermic peak is observed around 180°C in both nylon 6 and NCN5 samples annealed at 170 and 190°C, which might be related to the melting of microcrystals formed in the amorphous regions during annealing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3116–3122, 2006     

Crystallization behavior of polypropylene in polypropylene/nylon 6 blend

This article describes the crystallization behavior of polypropylene (PP) in the presence of a crystallizable polymer, namely, nylon 6, in the binary blend of PP/nylon 6 in the composition range from 0 to 30 wt % of nylon 6 content in the blend. The crystallization behavior was studied through variation of the crystallinity with the blend composition and changes in the crystallization exotherms were recorded by differential scanning calorimetry (DSC) and the spherulite morphology was observed via polarized light microscopy (PLM). Comparison of the crystallization exotherms and melting endotherms revealed some differences which are attributed to the role of a sufficiently high thermal energy of the nylon 6 crystals on the melting of PP. The crystallinity of PP decreased in the presence of nylon 6, whereas the crystallinity of nylon 6 increased considerably in the presence of PP. The rate of nucleation of PP on addition of nylon 6 decreased rapidly in the region 0–10 wt % nylon 6 content, and, thereafter, at a higher nylon 6 content, decrease of the nucleation rate was relatively slow. PLM observation revealed the presence of composite spherulites with PP spherulites grown on the surface of the already‐formed nylon 6 spherulites. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1153–1161, 1999     

Permeation of chlorinated hydrocarbons through nylon 6/ethylene–propylene rubber blends

Vapor transport offers one the unique ability to study structure–property relationships in polymers. An analysis of the transport of chlorinated hydrocarbons through nylon/ethylene–propylene rubber (EPR) blend membranes showed us how the permeation behavior varied according to the structure and morphology of the material under study. Binary blends were subjected to solvent transport studies. The solvent uptake increased with EPR content and decreased with nylon content. The behavior varied with the blend morphology. The effects of blend ratio, compatibilization, and dynamic vulcanization on the vapor permeation behavior of nylon/EPR blends were investigated in detail. The results from the vapor permeation studies were complimentary to those of the morphology studies. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3756–3764, 2004     

Study of parametric sensitivity in an autothermal nylon 6 reactor

The parametric sensitivity of an industrial autothermal nylon 6 reactor was studied. The sensitivities of the temperature maxima with respect to various parameters of the model are computed numerically. The sensitivity peaks were found to occur (almost) at the same value of the input parameter, thus confirming the generalized nature of the thermal parametric sensitivity criterion. It is shown that this criterion can easily be used to find safer regions of operation of the reactor. The variation of the number‐average chain length of the product, μ_nf, with the variation of input parameter, W₀, was also studied. A methodology was suggested to obtain the desired ranges of operation of the reactor which represent an optimal balance between the thermal sensitivity and the sensitivity of μ_nf. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 333–343, 1999