聚乙烯 -醋酸乙烯酯共聚物与马来酸酐的熔融接枝

在双螺杆挤出机中进行了聚乙烯－醋酸乙烯酯共聚物与马来酸酐的接杆反应，通过红外分析证实了接枝产物的存在，研究了醋酸乙烯酯质量分数、引发剂种类及接枝单体和引发剂用量地接枝反应的影响。结果表明，相对于100份乙烯醋酸乙烯酯，接枝单体和引发剂用量分别为2和0．3份较为适宜。     

接枝聚忆烯改性高分子复合PTC材料性能的研究

利用化学接枝法地线性低密度聚乙烯（LLDPE）进行接枝改性,研究发现适量接枝物的加入,明显改善了材料的PTC性能,使PTC强度提高了一个数量级,而TC性能基本不变,通过对比研究发现乙烯－醋酸乙烯酯共聚物（EVA）对高分子LLDPE－CB体系的PTC强度也有一定的改善作用,但不如接枝物。极性化学接枝物更有利于炭黑在LLDPE中均匀分散,使高分子复合PTC材料具有更好的稳定性。     

中国专利

喷涂聚乙烯塑料制品用的底漆的制造方法 一种喷涂聚乙烯塑料制品用的底漆的制造方法,其特征是分别制备a组分乙烯-α-烯烃共聚物或氯化乙烯-α-烯烃共聚物与其共混物的接枝共聚改性树脂、b组分乙烯-醋酸乙烯酯的改性共聚物或该改性共聚物与乙烯-醋酸乙烯酯共聚物的共混物、c组分氯化聚乙烯或氯化聚丙烯或两者的其混物、d组分醋酸乙烯酯-N-羟甲基     

马来酸酐接枝改性乙烯-醋酸乙烯醋共聚物热熔胶的研究

本文研究了以乙烯－醋酸乙烯酯共聚物熔融接枝马来酸酐作为基础聚合物制备热熔胶的方法．用正交设计法探讨单体、增粘剂、调节剂和引发剂用量对粘接性能的影响，而获得最佳热熔胶的配方。该热熔胶对尼龙纤维、金属、塑料和木材均具有较强的粘接能力。     

马来酸酐接枝改性乙烯—醋酸乙烯醋共聚物热溶胶的研究

本文研究了以乙烯－醋酸乙烯酯共聚物熔融接枝马来酸酐作为基础聚合物制备热熔胶的方法。用正交设计法探讨单体、增粘剂、调节剂和引发剂用量对粘接性能的影响，而获得最佳热熔胶的配方。该热熔胶对尼龙纤维、金属、塑料和木材均具有较强的粘接能力。     

氯乙烯-醋酸乙烯酯共聚物的后功能化研究

通过将氯乙烯－醋酸乙烯酯－丙烯酸羟乙醋共聚物（VAGF）与马来酸酐酯化接枝，制得带羟基的氯醋三元共聚物。探索了原料配比、催化剂用量、反应时间及反应温度对酯化接枝反应的影响，并用红外光谱进行表征。得到酯化反应的最佳条件为：催化剂用量为VAGF质量的0．8％，VAGF质量分数为15％，温度100℃，时间9h。氯乙烯－醋酸乙烯酯－丙烯酸羟乙酯三元共聚物的马来酸酐酯化活性高于氯乙烯－醋酸乙烯酯－乙烯醇三元共聚物。     

回收聚丙烯的亲水改性

利用回收聚丙烯固相接枝马来酸酐(MAH)、低温等离子体等,对聚丙烯进行亲水改性研究.以亲水性的MAH作为接枝单体,探讨了单体用量及引发荆用量等因素对固相接枝反应的影响.当乙烯-醋酸乙烯酯(EVA)含量为3%时,接触角最低可降到69.6°;而等离子体可以进一步改善亲水性,使接触角最低速54.0°.     

马来酸酐接枝改性EVA热熔胶的研究

通过正交实验,研究了在有机过氧化物的存在下,乙烯-醋酸乙烯酯与马来酸酐接枝共聚。其接枝物作为热熔胶的基础聚合物。探讨了原材料配比、单体、松香甘油酯和石蜡的用量对粘接性能的影响,最终获得了一种对金属、塑料、木材、纤维织物均有较强粘接力的热熔胶粘剂配方。     

乙烯－醋酸乙烯酯安全电缆

乙烯－醋酸乙烯酯安全电缆英国《欧洲橡胶杂志Ｎ９９３年１７５卷１１期３３页报道：英吉利海峡海底隧道钻掘机使用的电缆包皮是由拜耳公司Ｉ。ｅｖａＰｒｅｎｅ（乙烯一醋酸乙烯酯橡胶）制作的。为了具有良好的耐火性能，Ｉ。ｅｖａｐｒｅｎｅ填充了一种以氧化铝为基的阻...     

熔融法皂化EVA接枝MANa离聚物的制备及影响因素的研究

采用熔融法进行乙烯-醋酸乙烯酯共聚物(EVA)与马来酸钠(MANa)的接枝反应,并利用红外光谱对接枝物(EVAL-g-MANa)的结构进行了表征。结果表明,接枝物在1 575cm-1处出现了宽的羧酸盐的C=O特征伸缩振动峰,证明MANa已与EVAL发生接枝反应,生成了离聚物。运用正交设计分析了单体浓度、反应时间、反应温度、转速等因素对EVAL-g-MANa离聚物接枝率的影响,优化了离聚物的制备工艺。     

Reactive compatibilization of the poly(butylene terephthalate)–EVA blend by maleic anhydride. II. Correlations among gel contents,grafting yields,and mechanical properties

Correlations among the degree of crosslinking of ethylene vinyl acetate copolymer (EVA), the grafting yield of maleic anhydride (MAH) onto EVA, and the mechanical properties of the blends of poly(butylene terephtalate) (PBT) with EVA‐g‐MAH were investigated. The EVA was functionalized by melt grafting reaction in the presence of MAH and dicumyl peroxide (DCP) using a plasticorder. The grafting yield of MAH was increased by increasing the concentration of MAH and DCP. The flexural strength of PBT–EVA‐g‐MAH blends depends on both the grafting yield of MAH and the degree of crosslinking of EVA, while the crosslinked parts of EVA‐g‐MAH hindered rather than improved the tensile strength regardless of the increase of the grafting yield of MAH. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1305–1310, 2003     

Effect of blending sequence on the microstructure and properties of PBT/EVA‐g‐MAH/organoclay ternary nanocomposites

Ternary nanocomposites based on poly(butylene terephthalate) (PBT), maleic anhydride grafted poly(ethylene‐co‐vinyl acetate) (EVA‐g‐MAH), and organically modified montmorllonite (organoclays) were prepared through four different blending sequences in a Haake rheocord mixer: (1) To blend PBT, EVA‐g‐MAH and organoclays in one step; (2) First to prepare EVA‐g‐MAH/organoclay nanocomposite, then mix it with PBT to get the final nanocomposite; (3) To mix PBT with organoclays first, then the PBT/organoclay nanocomposite with EVA‐g‐MAH. (4) To mix organoclays with the PBT/EVA‐g‐MAH blend. The microstructure of the PBT/EVA‐g‐MAH/organoclay ternary hybrids was characterized by X‐ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that the blending sequence significantly influences the microstructure of PBT/EVA‐g‐MAH/organoclay ternary hybrids and the dispersion behavior of the organoclays in the polymer matrix. Tensile and impact properties of the hybrids were also studied. The results showed that the mixing sequence (2) gives the best tensile and impact strength due to its fine “sea‐island” morphology of PBT/EVA‐g‐MAH blend and good dispersion of the organoclays in the continuous PBT matrix.     

Morphology and properties of PBT/nylon 6/EVA‐g‐MAH ternary blends prepared by reactive extrusion

Morphology and properties of poly(butylene terephthalate) (PBT)/nylon 6 (PA6)/EVA‐g‐MAH ternary blends were investigated. The blends were prepared in a corotating, intermeshing, twin‐screw extruder. The incorporation of maleic anhyride (MAH) grafted onto ethylene‐vinyl acetate copolymer (EVA) (EVA‐g‐MAH) in the PBT/PA6 binary blends decreased the tensile and flexural strength but increased the impact strength, while the mechanical properties of the PBT/PA6 blends were decreased with increasing PA6 content regardless of the presence or absence of the EVA‐g‐MAH. The morphology studies of the ternary blends showed gross phase separation. The rheological properties of the ternary blends suggested that excessively high reactivity between amine end groups of PA6 and MAH grafted onto EVA makes the compatibility between PBT and PA6 worse, although EVA‐g‐MAH was expected to work as a compatibilizer for PBT/PA6 blends. The degree of reactivity between functional groups in PBT, PA6, and EVA‐g‐MAH was also examined by investigating the effect of blending sequence on the properties of the ternary blends.     

Melt grafting of poly(ethylene‐vinyl acetate) copolymer with maleic anhydride

Poly(ethylene‐vinyl acetate) (EVA) copolymer was melt grafted with maleic anhydride (MAH) in a twin screw extruder in the presence of peroxide. It is confirmed that MAH has been melt grafted on the backbone of EVA by FTIR using the method of hydrolysis. The NMR analysis suggests that the grafting reaction occurs on the tertiary carbon of main chain of EVA other than the methyl moiety of vinyl acetate (VA) group. The incorporation of VA groups onto the matrix shows a competitive effect on the grafting. The existence of VA groups promotes the extent of MAH graft onto EVA; nevertheless, it also weakens the crystallizability of main chain. When the content of peroxide initiator is 0.1 wt % based on the polymer matrix, the grafting degree increases with increasing the concentration of monomer. When the peroxide content is higher than 0.1 wt %, side reactions such as crosslinking or disproportionation will be introduced into this system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 841–846, 2006     

Grafting maleic anhydride onto EVA and effect on the physical and rheological properties of PETG/EVA-g-MAH blends

Maleic anhydride (MAH) was grafted onto ethylene vinyl acetate copolymer (EVA) in the internal mixer in the presence of dicumyl peroxide (DCP), and a prepared reactive compatibilizer, MAH-g-EVA, was blended with Poly (ethylene glycol-co-cyclohexane-1,4-dimethanol terephthalate) (PETG). The gel content determination and element analysis (EA) was performed to confirm the grafting reaction. It was found that grafting reaction of MAH on to EVA could compete with crosslinking reaction of DCP during the modification process. In addition, the introduction of small amount of MAH showed a great effect on reducing gel content by decreasing crosslink reaction. As MAH content increased, grafted MAH concentration increased, whereas the grafting yield decreased. It was also confirmed that MAH-g-EVA acted as a reactive compatibilizer in the blend with PETG, and enhanced compatibility by reacting with the hydroxyl end groups, OH, of PETG. Addition of EVA in the blend leads a plastic deformation of PETG, and MAH had a great effect on enhancing interfacial adhesion resulting in significant increasing of % strain; however, improved compatibility could not be changed much in low strain tensile strength and Young's modulus. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

EVA-g-MAH反应挤出研究及其在LDPE/MH体系中的应用

采用同向双螺杆研究了不同熔融指数的复合EVA熔融接枝马来酸酐,考察了引发剂用量、MAH用量对接枝率及熔体流动速率的影响.结果表明,接枝率随着马来酸酐、引发剂用量的增加而增加,熔体流动速率随着引发剂用量的增加而减少.通过制备的接枝物添加到阻燃体系中,考察了接枝率对体系性能的影响.     

Effect of dispersion state of organoclay on cellular foam structure and mechanical properties of ethylene vinyl acetate copolymer/ethylene‐1‐butenecopolymer/organoclay nanocomposite foams

In this study, our goal is to obtain lower density of ethylene‐vinyl acetate copolymer (EVA)/ethylene‐1‐butene copolymer (EtBC) foams without sacrificing mechanical properties. For this purpose EVA/EtBC/organoclay (Cloisite 15A, Closite 30B) nanocomposite foams were prepared. To investigate the effect of compatibilizer on the dispersion state of organoclay in cellular foam structure and mechanical properties of the EVA/EtBC/organoclay foams composites were prepared with and without maleic anhydride grafted EtBC (EtBC‐g‐MAH). The dispersion of organoclay in EVA/EtBC/organocaly foams was investigated by X‐ray diffraction and transmission electron microscopy. The EVA/EtBC nanocomposite foamswith the compatibilzer, especially EVA/EtBC/Cloisite 15A/EtBC‐g‐MAH foams displayed more uniform dispersion of organoclay than EVA/EtBC nanocomposite foams without the compatibilzer. As a result, EVA/EtBC/Cloisite 15A/EtBC‐g‐MAH foams have the smallest average cell size and highest 100% tensile modulus followed by EVA/EtBC/Cloisite 30B/EtBC‐g‐MAH foams. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3879–3885, 2007     

聚烯烃弹性体与马来酸酐的熔融接枝

以双螺杆挤出机作为反应器，比较了聚烯烃弹性体（POE），线性低密度聚乙烯（LLDPE）与马来酸酐（MAH）的熔融接枝反应。尽这两种树脂具有相近的支化度，但由于POE树脂的大支链对大分子自由基之间的偶合反应具有抑制作用，所以，POE/MAH接枝体系的接枝率明显高于LLDPE／MAH接枝体系，而且接枝产物保持了较好的流动性；酸酐在POE树脂上的接枝率随过氧化物和接枝单体用量的增加而增大。接枝树脂可以明显提高PE与铝之间的粘接强度。     

油气管道接口热收缩带用固定片的研制

利用聚合物共混技术,将一定量的EVA460,EVA150和丁基橡胶熔融混合,再将混合物熔融接枝马来酸酐(MAH),最后与一定量的二聚脂肪酸聚酰胺共混制成了高温高粘型热熔胶。用挤出机将其挤成胶膜后与交联聚乙烯基材,大孔径玻璃纤维网热复合制成固定片。经现场试验证明:固定片固定效果良好。     

相容剂对PVC／PA6体系形态结构的影响

研究了SMA—g—MAH、SEBS—g—MAH和EVA—g—MAH3种相容剂对PVC／PA6共混物的增容效果。结果表明,未添加相容剂的PVC／PA6（100／20）共混物的相容性不好;添加SEBS—g—MAH和EVA—g—MAH两种相容剂后,PVC／PA6共混物的相容性得到一定程度的改善;添加SMA—g—MAH相容剂后,PA6很均匀地分散在PVC基体中。