接枝功能化聚烯烃

聚烯烃功能化是目前人们普遍关注的热点.综述了国内外对聚烯烃进行功能化的各种方法,其中重点讨论了聚烯烃的接枝功能化,并对接枝物的结构性能与应用作了简要介绍.     

聚烯烃的功能化

叙述了聚烯烃通过共聚、接枝、高分子反应、低分子量化、复合化、交联化以及新的催化技术开发所得各种功能性聚烯烃的特点及其应用。     

聚烯烃的功能化改性研究进展

介绍了功能化聚烯烃的合成方法和应用情况。根据功能化聚烯烃上的功能基团的位置和数量,将功能化聚烯烃的合成方法分为三类,并分别进行了讨论,认为利用反应性基团与烯烃共聚合,然后功能化改性,是目前制备功能化聚烯烃最有效的方法。最后概述了功能化聚烯烃的应用。     

聚烯烃功能化进展

重点介绍了聚烯烃功能化常用的方法——氯化反应、磺化反应和聚烯烃与马来酸酐反应。聚烯烃与马来酸酐反应有3种方法(即溶液接枝、熔融接枝和固相接枝),其中,溶液接枝成本高,污染大,应用范围较小：熔融接枝是当今主要采用的方法,共单体的选择和多单体接枝的反应机理是其研究的重点;固相接枝法主要为粉末接枝,是一种有待进一步研究的新方法。     

锂离子电池聚烯烃隔膜改性及功能化研究

综述了近年来国内外锂电池聚烯烃隔膜的改性及功能化研究进展,分类介绍了锂电池聚烯烃隔膜的制造方法和性能的表征指标,及孔径分布、孔隙率、润湿性、耐热性、安全性、机械强度等方面的改性状况.     

聚烯烃接枝改性功能化的研究进展

综述了聚烯烃本体接枝改性和表面接枝改性在近两年来的研究进展 ,主要体现在接枝方法的优化、接枝物的扩充、接枝机理及反应动力学的研究以及接枝反应的控制、接枝物的高分子设计等方面     

国外聚烯烃技术进展

就催化剂、聚烯烃功能化及新产品开发三方面论述近年来聚烯烃工业的技术进展情况。     

聚烯烃流变学的研究进展

聚烯烃流变学的研究对聚烯烃合成、加工及模具的设计等均具有重要的意义。综述了近年来在聚烯烃流变学方面的研究进展,重点讨论了聚乙烯、聚苯乙烯、聚丙烯及聚烯烃共混体等的流变学研究动态,并对聚烯烃流变学的发展趋势及应用前景作了展望。     

基于RAFT聚合策略合成功能化聚烯烃嵌段聚合物的研究进展

首先介绍了可逆加成-断裂链转移聚合（RAFT）的聚合机理及其常用的RAFT试剂,并与其它两种活性可控自由基聚合[氮氧化合物媒介的自由基聚合（NMP）和原子转移自由基聚合（ATRP）]进行了简单的优缺点对比。其次,介绍了近些年在基于RAFT聚合制备功能化聚烯烃嵌段聚合物研究中取得的进展,重点综述了制备功能化聚烯烃嵌段聚合物时所采用的6种方法,包括①烯烃配位聚合与RAFT聚合相结合;②阴离子聚合与RAFT聚合相结合;③阳离子聚合与RAFT聚合相结合;④Click反应与RAFT聚合相结合;⑤开环聚合与RAFT聚合相结合;⑥叶立德活性聚合与RAFT聚合相结合。最后,对基于RAFT聚合策略设计合成功能化聚烯烃嵌段聚合物的研究前景与实际应用进行了展望。     

功能化聚丙烯研究进展

综述了国内外聚丙烯(PP)功能化的方法,主要包括丙烯与极性单体直接共聚法、中介物功能化法、接枝改性法等,重点讨论了后两种功能化方法。通过化学反应在PP分子结构中引入极性基团是达到PP功能化的根本途径。     

Adhesion of maleic anhydride functionalized polyolefins and blends

We study three new classes of olefin‐based polymer, low‐molecular‐weight homopolypropylene (LMW‐hPP), syndiotactic‐rich polypropylene (srPP), and random propylene polymer (RPP). RPP is a random propylene/ethylene copolymer. By blending LMW‐hPP with 20 wt % of a maleic anhydride (MA) functionalized srPP (MA‐srPP) or MA functionalized RPP (MA‐RPP) instead of a commercial MA‐iPP (maleic anhydride‐grafted‐isotactic polypropylene), adhesion to a polar substrate, such as polyester (Mylar), is greatly enhanced. Effects of crystallinity controlled by either stereoregularity or comonomer incorporation and molecular weight of these MA functionalized propylene‐based polymers on adhesive performance are discussed. To further understand the mechanisms of enhanced adhesion, Sum Frequency Generation (SFG) spectroscopy is used to evaluate the migration of MA‐srPP in LMW‐hPP towards the interface when contacting a polar sapphire substrate. It shows that the buried interface between the LMW‐hPP/MA‐srPP blend (wt ratio = 80/20) and sapphire has the same characteristic spectrum as the MA‐srPP/sapphire interface, suggesting the enrichment of MA‐srPP in the interfacial polymer when the blend is in contact with sapphire. Also, vibrational modes of C=O have been detected at both the blend/sapphire and MA‐srPP/sapphire interfaces, further indicating that the interfacial polymer contains MA groups. Besides Mylar, adhesion to the non‐polar iPP substrate is also studied. The adhesion mechanisms to these polar and non‐polar substrates are explained in terms of our adhesion model. Applications of these MA functionalized polyolefins and blends are envisioned in the tie‐layer and adhesive areas. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39855.     

Metallocene‐based functionalized polyolefins as compatibilizers in polyolefin nanocomposites

This article reports a study of some functionalized polyolefins evaluated as compatibilizers in polyethylene nanocomposites. The functionalized polymers were prepared by direct metallocene‐mediated copolymerizations of ethylene and a functional comonomer. The prepared nanocomposites were evaluated for mechanical and barrier property enhancement. A good combination of mechanical and barrier properties was obtained with the metallocene‐based functionalized polyethylene. The toughness–stiffness balance was better than or comparable to that achieved with conventional functionalized polymers such as maleic anhydride grafted polyethylene. The results also indicated that these metallocene‐based functionalized polyolefins, when used as compatibilizers, could have relatively higher molar masses and lower functionality than those of conventional post‐reactor‐modified compatibilizers, and so the drawbacks associated with the latter could be avoided. Their inherent properties could also further improve the final nanocomposite properties. This was attributed to the more homogeneous nature of metallocene‐catalyzed polymers in comparison with post‐reactor‐modified products. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1094–1100, 2004     

Use of oxazoline functionalized polyolefins and elastomers as compatibilizers for thermoplastic blends

Oxazoline functionalized polypropylene, polyethylene, ethylene propylene copolymer (E/P), and styrene ethylene/butylene styrene copolymer (SEBS) were studied as compatibilizers in blends of polyolefins with polyesters and polyamides. The blends investigated were polypropylene/polyamide 6, polypropylene/polybutylene terephtalate, and polyethylene/polyamide 6, with engineering thermoplastic contents of 30 wt %. The blends were prepared in a twin-screw midiextruder, and injection molded with a mini-injection molding machine. The effect of compatibilizing on the morphology and mechanical properties of the blends was of interest. Compatibilization substantially improved the toughness of all tested blends. Their strength and stiffness remained at the level of the binary blends when polypropylene or polyethylene based compatibilizers were used, but slightly decreased with other compatibilizers. Morphological studies showed that the particle size was reduced, and the adhesion of the dispersed phase to the matrix improved by compatibilization. The effect of unfunctionalized polyethylene, polypropylene, E/P, and SEBS was also studied to compare the compatibilizers with them. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1923–1930, 1998     

聚烯烃共混体系反应性增容研究的进展

综述了近期国内外通过将能发生化学反应的聚合物进行熔融共混、加入能与共混组分起反应的聚合物、添加能与共混组分在熔融共混过程中形成共聚物或产生交联的低分子化合物 3种方法进行聚烯烃共混体系反应性增容研究的进展     

现代活性染料技术进展

活性染料是一类有发展前途的重要棉用染料。本文从当前环境和生态保护要求出发阐述了现代活性染料的技术进展,包括现代活性染料的结构、品种以及适应新纤维与新染色技术要求的活性染料等各方面的发展,对现代活性染料的品种结构调整和技术创新具有重要的参考价值。     

国外农用功能性聚烯烃覆盖材料的发展动态

分别就国外近年在耐老化棚膜、流滴棚膜、光选择性棚膜、各类地膜以及覆盖材料的回收方面所做的工作进行介绍。     

Multiple surface structures in polyolefins formed by modification methods

New methods for the formation of multiple surface structures in polyolefins were developed both at the molecular and macromolecular levels, which produced a high local nonuniformity of surface properties. In particular, I obtained varied molecular structures at the surface as a result of consecutive heterophase fluorination and sulfonation reactions of the polymers. Nonuniform macroscopic surface structures were formed with dosed thermal and deformation treatments of prefluorinated polymeric materials with the partial destruction of the formed modified layer and the subsequent predominant sulfonation of the disclosed macroscopic regions of the initial nonfluorinated polymer. The kinetics of the multiplet structure formation were studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95:1198–1208, 2005     

衣康酸及其衍生物反应挤出改性聚烯烃的研究进展

通过反应挤出的方式, 采用衣康酸及其衍生物对聚烯烃进行接枝改性, 可以显著改善材料性能, 特别是与其他高分子材料的相容性。本文从影响聚烯烃接枝改性的各个因素:聚烯烃类型、引发剂类型以及添加剂出发, 详细论述了国内外研究者的研究进展, 重点阐述了各个因素对聚烯烃改性机理、产物链结构的影响, 认为反应挤出接枝产物链段结构以及螺杆结构对反应挤出的影响这两方面值得进一步研究。     

官能化溶聚丁苯橡胶研究进展

介绍了溶聚丁苯橡胶的发展历程,从官能化引发剂、官能化封端改性等方面详述了官能化溶聚丁苯橡胶的研究进展及溶聚丁苯橡胶的官能化技术在轮胎用橡胶方面的重要作用。将官能化技术和偶联技术结合而产生的官能化星型溶聚丁苯橡胶是丁苯橡胶研究的一个重要方面。