MAH对PP木塑复合材料的直接反应增容研究

通过过氧化二异丙苯、马来酸酐、木粉和聚丙烯的直接反应挤出,实现了聚丙烯木塑复合材料的反应增容。利用扫描电子显微镜观测了复合材料冲击断面形貌。测试了复合材料的负荷变形温度和力学性能。结果表明,直接反应增容后,复合材料木塑两相结合情况明显改善;负荷变形温度、拉伸强度和弯曲强度显著提高,其最大值分别达115℃4,1 MPa和63 MPa,比增容前分别提高15℃3,7%和31%;而断裂伸长率和冲击强度则有所下降。     

增容剂对废旧PS／PE-HD／废旧ABS／木粉复合材料性能的影响

以过氧化二异丙苯（DCP）为引发剂，在转矩流变仪中分别制备了丙烯酸（AA）接枝聚苯乙烯（PS-g-AA），马来酸酐（MAH）、AA接枝PS[PS-g-（MAH-co-AA）]和MAH、醋酸乙烯酯（VAc）接枝PS[PS-g-（MAH-co-VAc）]三种增容剂。经红外光谱分析，所得产物均为目标产物。接枝率测定结果表明，三种增容剂中PS-g-（MAH-co-VAc）的接枝率最高，达到2．43％。研究了三种增容剂对木塑复合材料性能的影响。结果表明：三种增容剂均可提高木塑复合材料的力学性能和加工性能。扫描电镜测试结果同时表明，增容剂能更好地提高木塑复合材料中基体与木粉的界面黏结强度。     

甲基化木粉与PE-g-MAH对木粉/HDPE复合材料力学性能的协同作用研究

主要研究了木粉表面甲基化改性和增容剂马来酸酐接枝聚乙烯(PE-g-MAH)对木粉/高密度聚乙烯(HDPE)复合材料力学性能的协同作用.木粉经表面甲基化处理后,与10％PE-g-MAH协同使用,甲基化木粉/PE-g-MAH/HDPE复合材料的拉伸强度、弯曲强度和冲击强度均明显高于未改性木粉/PE-g-MAH/HDPE复合...     

界面改性对HDPE木塑复合材料性能的影响

采用二辊开炼和压制成型的方法,以马来酸酐接枝聚乙烯(MAPE)、马来酸酐(MAH)和(或)过氧化二异丙苯(DCP)处理木粉制备高密度聚乙烯(HDPE)基木塑复合材料(WPC),考察了几种方法对复合材料力学性能、动态热机械性能及加工性能的影响,并借助扫描电子显微镜( SEM)对复合材料界面进行了形貌分析.结果表明:MAH和DCP共同改性HDPE基WPC,在改善复合材料界面相容性的同时也提高了基体强度,材料综合性能最佳.     

HDPE/木粉复合材料的性能研究

研究了不同种类的增容剂对高密度聚乙烯(HDPE)木/粉复合材料性能的影响,并研究了增容剂含量、木粉含量对复合材料力学性能及形态结构的影响。结果表明,HDPE木/粉复合材料的拉伸强度、弯曲强度均随马来酸酐接枝HDPE(HDPE-g-MAH)含量的增加而增大;复合材料的缺口冲击强度随甲基丙烯酸缩水甘油酯接枝低密度聚乙烯的增加而提高;复合材料的拉伸强度、弯曲强度随木粉含量的增加而增大;而缺口冲击强度则随木粉含量的增加呈降低趋势。     

聚乙烯热熔胶增容聚乙烯基木塑复合材料的研究

采用废木粉和高密度聚乙烯制备复合材料,并采用一种聚乙烯热熔胶作为相容剂以增进憎水性的聚乙烯基材和亲水性的木粉界面的相互作用。评价了该热熔胶的增容效果,并对其增容机理进行了详细论述。研究结果表明:该热熔胶的主要成分为马来酸酐接枝高密度聚乙烯(PE-HDg-MAH)和乙烯-醋酸乙烯酯共聚物(EVA);添加木粉有利于弯曲强度和弯曲模量的提高,但使冲击强度和拉伸强度迅速下降;该热熔胶可明显提高复合材料的力学性能,并且木粉的填充量越高,则增容作用就越明显;当木粉的用量为50％时,使用该热熔胶可使复合材料的拉伸强度、弯曲强度、弯曲模量和冲击强度分别提高115．6％、66．7％、38．1％和67％;基于这些结果可知,该热熔胶可显著提高聚乙烯基材／木粉界面处的亲和力,是聚乙烯基木塑复合材料理想的增容剂。     

马来酸酐接枝改性聚丙烯及其在木塑复合材料中的应用

通过双螺杆挤出机聚丙烯熔融挤出接枝马来酸酐制备马来酸酐接枝聚丙烯（PP-g-MAH）;研究了接枝单体马来酸酐（MAH）、引发剂DCP及共单体St等对聚丙烯（PP）熔融接枝MAH的接枝率的影响。将制备的接枝物应用于木塑复合材料中,发现木粉与聚丙烯之间的界面结合有了明显的改善,添加的PP-g-MAH增强了木粉和聚丙烯基体之间的黏合性,使两相结合得更紧密,进而提高了木塑复合材料的力学性能。     

MAH原位接枝HDPE及其对HDPE/N-PCB复合材料力学性能的影响

将马来酸酐(MAH)、过氧化二异丙苯(DCP)、苯乙烯(St)、高密度聚乙烯(HDPE)和废印刷电路板非金属粉末(N-PCB)直接反应挤出,制备了HDPE/N-PCB复合材料,并研究了MAH用量对HDPE/N-PCB复合材料力学性能影响。对HDPE/N-PCB复合材料抽提残留物的红外分析结果表明,在HDPE/N-PCB复合材料中加入DCP、St、MAH之后,通过DCP引发HDPE原位接枝MAH,并随即与N-PCB粉末表面的羟基反应而起到了桥联作用,可改善HDPE基体与N-PCB粉末两相的界面作用。MAH反应增容后的HDPE/N-PCB复合材料与增容前相比,其拉伸强度、弯曲强度、缺口冲击强度及断裂伸长率的最大增幅分别为36%、12%、208%和262%。     

MAPE含量对PE木塑复合材料冲击强度的影响

以高密度聚乙烯(PE-HD)和马来酸酐接枝聚乙烯(MAPE)共混物为塑料基体,以木粉(WF)为填料,采用压制成型法制备了木塑复合材料。研究了MAPE含量对塑料基体和木塑复合材料冲击强度的影响。结果表明,MAPE含量对MAPE/PE-HD塑料基体和木塑复合材料的冲击强度影响显著;保持MAPE和PE-HD的总含量不变时,当木粉含量为30 %时,木塑复合材料的冲击强度随MAPE含量的增大而逐渐减小;当木粉含量为70 %时,木塑复合材料的冲击强度随MAPE含量的增加而逐渐增大。     

LDPE基木塑复合材料制备工艺及性能研究

以马来酸酐(MAH)和(或)过氧化二异丙苯(DCP)复合处理木粉(Wood)或预先将MAH和DCP与低密度聚乙烯( LDPE)进行熔融接枝反应,采用挤出混炼和注射成型的方法制备了LDPE基木塑复合材料.考察了MAH、DCP含量及制备工艺等对复合材料加工性能、力学性能及动态热机械性能的影响;并借助扫描电子显微镜分析了其作用机理.结果显示:与先制备的MAH-g-PE相比,直接用MAH和DCP复合处理木粉所制备木粉/LDPE复合材料(木粉质量分数40％)具有更优的力学性能,其冲击强度提高了40％左右,而且加工平衡扭矩仅为前者的1/3;SEM分析表明:前者中木粉存在明显的团聚现象;此外,MAH和DCP均有相对最佳用量,分别为木粉的0.5％和LDPE的0.3％ ～0.5％.     

Deinking Sludge: A New Biofiller for HDPE Composites

This paper studies the potential of deinking sludge as a biofiller in high-density polyethylene composites. The physicochemical properties of deinking sludge were investigated by X-ray, Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy, and fiber quality analyses. Deinking sludge/high-density polyethylene formulations were produced according to an experimental design. Variables were deinking sludge wt% (5, 12.5, and 20) and maleic anhydride polypropylene content (2 and 4%). The influences of deinking sludge and maleic anhydride polypropylene on the mechanical and morphological properties of deinking sludge/high-density polyethylene composites were investigated. Rigidity and tensile strength increased with fillers content. Maleic anhydride polypropylene ameliorated interfacial interaction and the dispersion of deinking sludge. Maximum properties were predicted at 3.5% of maleic anhydride polypropylene and 15.8% of deinking sludge.     

Conceptualizing Physical and Chemical Interactions in the Compatibilized HDPE/PA6 and HDPE/EVOH Pairs: Theoretical and Experimental Analyses

Physical/chemical interaction in blends of high-density polyethylene with polyamide 6 and polyethylene-co-vinyl alcohol compatibilized with maleic anhydride-grafted high-density polyethylene was discussed. The performance of maleic anhydride-grafted high-density polyethylene was assessed by domain size variation and interfacial adhesion examination. Analysis of impact strength elucidated physical interaction improvement by compatibilization (entanglements and hydrogen bonding), while chemical reactions between ?OH and ?NH (from polyethylene-co-vinyl alcohol and polyamide 6, respectively) and ?COOH functional groups resulting from ring-opening of maleic anhydride determined interfacial adhesion reinforcement, where interfacial adhesion parameter changed from 0.75 for noncompatibilized to 0.96 compatibilized high-density polyethylene/polyamide 6, but remained unchanged for high-density polyethylene/polyethylene-co-vinyl alcohol blends, from 0.98 to 1.02.     

以酯基为连接基的非离子双子表面活性剂的合成

以蓖麻油酸（RA）、聚乙二醇（600）为原料,马来酸酐为连接基,合成了一种新型的非离子双子表面活性剂MARAPEG-15,考察了催化剂用量、物料摩尔配比、反应时间及温度对酸酐与蓖麻油酸聚乙二醇硼酸酯酯化的影响,并测定了产物的临界胶束浓度和表面张力。马来酸酐与蓖麻油酸聚乙二醇硼酸酯酯化较佳的工艺条件为：催化剂用量为总质量的3%,n（酸酐）∶n（蓖麻油酸聚乙二醇硼酸酯）为3.1∶2,反应温度为110℃,时间为4 h;硼酸酯键水解时间为1.5 h。产物的表面张力及其临界胶束浓度为γCMC=35.73 mN/m,CMC=1.96×10-5mol/L。     

控制聚乙烯熔融接枝马来酸酐副反应的研究进展

介绍了聚乙烯熔融接枝马来酸酐的反应机理,引发剂用量、单体用量、螺杆转速、反应温度等对反应的影响。综述了熔融接枝过程中控制副反应发生的方法,包括加入给电子体、共聚单体、新型引发剂或复配引发剂以及加入其他有机物添加剂,同时比较了加入这些物质的有效性。展望了聚乙烯熔融接枝马来酸酐的发展趋势。     

Grafting maleic anhydride and comonomers onto polyethylene

Grafting dicarboxylic anhydrides onto polyolefins has great practical importance. The process of grafting maleic anhydride onto high-density polyethylene in the presence of various comonomers in an intermeshing corotating twin-screw extruders was studied. Three types of comonomers were investigated: (i) vinyl monomers, including styrene and methacrylic acid; (ii) esters of dicarboxylic acids forming succinic groups after grafting, such as fumaric acid; and (iii) esters of fumaric and maleic acid and ethylenically unsaturated cyclic dicarboxylic anhydrides, such as Diels–Alder adducts of maleic anhydride; and (iv) dienes and dodecenyl succinic anhydride. © 1995 John Wiley & Sons, Inc.     

HDPE-g-MAH和POE-g-MAH对HDPE/PA6共混物性能的影响

分别以高密度聚乙烯接枝马来酸酐（HDPE-g-MAH）和乙烯-辛烯共聚物接枝马来酸酐（POE-g-MAH）作为相容剂,通过熔融挤出法对PE100/PA6共混物进行共混改性。研究了两种相容剂的用量对共混物力学性能、热性能和微观结构的影响。结果表明：HDPE-g-MAH与POE-g-MAH相比,都使体系发生反应性增容的同时,对共混物的结晶性更为有利,使得PE100/PA6/HDPE-g-MAH的综合性能更好,更适合作为PE100耐热改性时的增容剂。     

Functionalization of polyolefins with maleic anhydride in melt state through ultrasonic initiation

The functionalization reaction of high-density polyethylene (HDPE), linearly low-density polyethylene (LLDPE), polypropylene (PP) and EPDM rubber with maleic anhydride (MAH) in melt state through ultrasonic initiation was studied. The effect of ultrasonic intensity on the percentage of grafting, viscosity-average molecular weight, melt flow rate and gel content of the functionalized products were investigated by means of chemical titration, Fourier-transform infra-red spectroscopy (FT-IR), intrinsic viscosity and melt flow rate, etc. The molecular structures of the functionalized products prepared via ultrasonic initiation and via peroxide initiation were characterized by ¹H NMR spectroscopy. The results show that the functionalization reaction of HDPE, LLDPE and EPDM with MAH can be realized by ultrasonic initiation. This reaction mainly consists of the chain scission under ultrasonic irradiation, the end chain reaction of the produced macroradicals with MAH, and the terminated reaction of the produced succinyl radicals with the macroradicals or H* radicals through recombination or dismutation. The functionalized product through ultrasonic initiation mainly consists of the products containing an anhydride ring attached to the chain terminus. And the products prepared through peroxide initiation mainly contain an anhydride ring grafted on the side chain.     

Chlorocarboxylation of polyethylene. I. Preparation and structure of chlorocarboxylated polyethylene

Chlorocarboxylated polyethylene (CCPE) is produced by simultaneous reaction of chlorine and maleic anhydride (MA) with polyethylene (PE). Low concentrations of the carboxyl groups in CCPE have been quantitatively estimated by dye interaction method and non-aqueous titration procedure. IR spectroscopic data are presented for the structural characterization of CCPE. During chlorocarboxylation, maleic anhydride can be anchored to the backbone chlorinated PE (CPE) chain as a chlorinated single monomeric unit without forming any graft copolymer of short branches.     

Chlorocarboxylation of polyethylene. II. Reaction mechanism of the process

Chlorocarboxylated polyethylene (CCPE) is produced by simultaneous reaction of chlorine and maleic anhydride (MA) with polyethylene (PE). Hydrogen atoms on the PE chain are substituted either by chlorine atoms or by maleic anhydride moieties. The reaction mechanism involves creation of an active site, i.e. a radical on the PE chain. There is competition between chlorine and MA molecules for the reaction with this macroradical. Chlorine reacts to give chlorinated polyethylene (CPE) type segments, while MA reacts as a single unit (as chloro derivative) without forming any graft copolymer. There is a marked reduction in the rate of chlorination of PE due to the presence of MA. This is probably due to the competitive nature of the process and the radical scavenging action of MA.