MAH—g—PP对PP／EVAL共混体系的增容作用

系统研究了不同组成及配比的马来酸酐接枝聚丙烯（ＭＡＨ－ｇ－ＰＰ）及其用量对聚丙烯（ＰＰ）与乙烯－乙烯醇共聚物（ＥＶＡＬ）的共混体系（ＰＰ／ＥＶＡＬ）力学性能借用Ｂｒａｂｅｎｄｅｒ塑化仪测试了ＰＰ／ＥＶＡＬ／ＭＡＨ－ｇ－ＰＰ共混体系的加工性能。结果表明,ＭＡＨ－ｇ－Ｐ接枝物对ＰＰ／ＥＶＡＬ共混体系有较好的增容作用,适量加入,可使ＰＰ／ＥＶＡＬ共混体系的力学性能明显提高,而加工性能基本不变。     

马来酸酐接枝聚乙烯与铝箔热复合的研究

本文报道了马来酸酐接枝聚乙烯（ＭＡＨ－ｇ－ＰＥ）与铝箔的热粘接性能，并实验确定了热复合所需的温度、压力、时间条件以及接枝率的影响。另外，发现混入１０％乙烯醋酸乙烯共聚物（ＥＶＡ）可明显提高与铝箔的粘接性。     

聚乙烯接枝改性及其与铝的粘接性

本文研究了聚乙烯／乙烯－醋酸乙烯共聚物和聚乙烯／乙烯－丙烯酸共聚物的共混物以及马来酸酐接枝聚乙烯中箔的粘结性能。红外光谱证实反应产物为接枝产物。并考查了热复合工艺条件对离强度的影响,同时,发现在ＭＡＨ－ｇ－ＰＥ中加入１０％的ＥＶＡ可明显提高铝箔的粘结性,扩大了非极性聚乙烯的应用范围。     

铝塑复合带用树脂的研制

研究了以高度聚乙烯（ＨＤＰＥ）接枝马来酸酐（ＭＡＨ）为原料，制备铝塑复合带用树脂的技术。探讨了引发剂及接枝单体用量对熔体流动速率、接枝率、剥离强度的影响。结果表明：ＨＤＰＥ经过接枝马来酸酐并混配其它树脂可制得与ＥＡＡ（乙烯－丙烯酸共聚物）相媲美的铝塑复合带用树脂。     

PE,EVA及LDPE／EVA共混物辐照特性的研究

本文在对乙烯－醋酸乙烯共聚物（ＥＶＡ）和聚乙烯（ＰＥ），低密度聚乙烯（ＬＤＰＥ）、线性低密度聚乙烯（ＬＬＤＰＥ）及高密度聚乙烯（ＨＤＰＥ）在＾６０Ｃｏγ射线辐照前后的性能进行比较的基础上，着重研究了ＬＤＰＥ／ＥＶＡ共混物在＾６０Ｃｏγ射线辐照前后的拉伸性能和交联度的变化，以及ＥＶＡ添加量、ＶＡ含量及熔体流动速率（ＭＦＲ）对这些变化的影响。     

PA－66／（PE／EPDM）－g－MAH共混增韧的研究

本文研究了尼龙－６６（ＰＡ－６６）与聚乙烯（ＬＤＰＥ）共混物的力学性能。结果表明，用马来酸酐接枝聚乙烯和三元乙丙橡胶（ＥＰＤＭ）改善了与基体ＰＡ－６６的相容性。添加弹性体ＥＰＤＭ，使之生成（ＰＥ／ＥＰＤＭ）－ｇ－ＭＡＨ共聚物，可以大幅度度地提高ＰＡ－６６／（ＰＥ／ＥＰＤＭ）－ｇ－ＭＡＨ冲击强度，同时熔体粘度随温度的变化趋于平缓，吸水率有所下降。     

磨盘形力化学反应器中LDPE固相力化学接枝MAH的研究

研究了磨盘碾磨中ＨＤＰＥ、ＬＤＰＥ、ＬＬＤＰＥ和ｍＰＥ的粉碎和降解以及ＬＤＰＥ的固相力化学接枝。将ＬＤＰＥ与马来酸酐共碾磨,制备了低密度聚乙烯－马来酸酐共聚物（ＬＤＰＥ－ｇ－ＭＡＨ）。采用ＩＲ、ＤＳＣ和化学滴定等方法对所制备的ＬＤＰＥ－ｇ－ＭＡＨ进行了分析表征。系统研究了磨盘转速、碾磨次数、低密度聚乙烯与马来酸酐配比等因素对产物接枝率的影响。结果表明,通过磨盘碾磨的力化学反应,ＭＡＨ在ＬＤＰＥ上的     

PA—66／（PE／EPDM）—g—MAH共混增韧的研究

本文研究了尼龙－６６（ＰＡ－６６）与聚乙烯（ＬＤＰＥ）共混物的力学性能。结果表明，用马来酸酐接枝聚乙烯和三元乙丙橡胶（ＥＰＤＭ）改善了与基体ＰＡ－６６的相容性。添加弹性体ＥＰＤＭ，使之生成（ＰＥ／ＥＰＤＭ）－ｇ－ＭＡＨ共聚物，可以大幅度地提高ＰＡ－６６／（ＰＥ／ＥＰＤＭ）－ｇ－ＭＡＨ冲击强度，同时熔体粘度随温度的变化趋于平缓，吸水率有所下降。     

废报纸粉填充聚丙烯材料的研究

本文介绍废报纸粉填充聚丙烯（ＰＰ）的研制。通过在体系中加入高分子偶联剂马来酸酐（ＭＡＨ）接枝ＰＰ（ＭＡＰＰ）来改善纸粉与ＰＰ基体的相容性，并针对纸粉填充后材料变脆的问题，用乙丙橡胶（ＥＰＤＭ）和乙烯醋酸乙烯共聚物（ＥＶＡ）对材料进行增韧，均取得显著的效果。所制材料的纸粉填充量（质量分数）可高达５０％～６０％，价廉、质轻、其主要性能好于桑塔纳轿车用木粉填充ＰＰ板，可望有较好的应用前景。当纸粉填充量（质量分数）为４０％～５０％时，主要性能：弯曲强度６９．０１～７４．８３ＭＰａ，杨氏弯曲模量２６４０～２９９６ＭＰａ，冲击强度１３．２５～１３．５０ｋＪ／ｍ２。     

水解对乙烯—乙酸乙烯共聚物乳液复合的影响

乙烯－乙酸乙烯共聚物（ＥＶＡ）乳液在ＮａＯＨ作用下进行表面水解处理后,加入甲基丙烯酸甲酯（ＭＭＡ）,在过硫酸铵引发下进行复合反应。对复合乳胶粒的凝胶质量分数的测定、热分析及动态粘弹性的表征表明,随ＥＶＡ乳胶粒表面水解度的增大,ＭＭＡ在其表面的接枝率增大,体系的交联程度随之增大,两相相容性得到改善。此外还探讨了复合配比及加入少量丙烯酸对复合体系的影响。     

Structure and properties of blends of poly(ethylene-co-vinyl alcohol) with poly(styrene-co-maleic anhydride)

In the present study, ethylene/vinyl alcohol (EVAL) copolymers with different hydroxyl contents were melt mixed with styrene/maleic anhydride (SMA) copolymers. These two copolymers have functional groups capable of reacting intermolecularly, giving stable products. All EVAL copolymers were prepared from the same ethylene/vinyl acetate (EVA) copolymer by controlled hydrolysis. The blends, prepared at constant temperature and rotation speed in the rheomixer, were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermo-gravimetric analysis, as well as mechanical properties and extraction experiments. All the above measurements lead to the conclusion that a certain part of hydroxyls of EVAL have reacted with anhydride groups of SMA, leading to the formation of branched and cross-linked products. The effect of (1) the molar ratio of hydroxyl/maleic anhydride functional groups, (2) the overall concentration of the functional groups, and (3) the mixing time on the structure and properties of the blends are discussed. Emphasis is given on the influence of these factors on the tensile strength, the elongation at break, and impact strength of the products. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 983–999, 1997     

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     

乙烯—醋酸乙烯酯共聚物的化学接枝改性

综述了乙烯－醋酸乙烯酯共聚物的化学接枝方法,重点探讨了乙烯－醋酸乙烯酯与马来酸酐的接枝原因,并对接枝物的表征及应用加以论述。     

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     

Use of pyrolysed oil shale as filler in poly(ethylene‐co‐vinyl alcohol)

The pyrolysed oil shale (POS) obtained from the pyrolysis of bituminous rock was used as filler in poly(ethylene‐co‐vinyl alcohol) (EVAL). The effects of vinyl alcohol content in the EVAL and the particle size of pyrolysed oil shale in the mechanical properties were investigated. The EVAL was prepared by hydrolysis of poly(ethylene‐co‐vinyl acetate) (EVA) with 8 and 18 wt % of vinyl alcohol content. The composites were prepared in a rotor mixer at 180°C with concentration of pyrolysed oil shale up to 5 wt %. Stress–strain plots of compression‐molded composites showed a synergic behavior in the mechanical properties for low concentrations (1–5 wt %) of POS in all particle sizes and EVAL used. Such behavior indicates a close packing and strong interactions between the inorganic filler and the polymer. Increasing of the vinyl alcohol content of EVAL improved the compatibility between the polymer and filler, but decreasing the POS particle size had no effect on the properties. The modulus and the ultimate tensile strength also increased in all concentrations of POS for both EVAL. Mechanical properties and dynamic mechanical analysis also demonstrated the compatibility between EVAL and POS. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1658–1665, 2004     

EVA对HDPE光交联反应的影响

采用测定凝胶含量的方法,以二苯甲酮(BP)作为光引发剂、三羟甲基丙烷三丙烯酸酯(TMP-TA)为交联剂,研究了辐照时间、乙烯-醋酸乙酯共聚物(EVA)含量对EVA/HDPE复合材料光交联的影响,并且考察了光交联后EVA/HDPE复合材料的力学性能。研究结果表明,EVA的加入会显著改变体系的凝胶含量;而辐照时间对EVA/HDPE体系交联反应影响很大;体系的力学性能随着EVA含量的增加而变化。     

PP/EVAL/PP-g-MAH动态硫化体系的结构与性能研究

研究了聚丙烯/皂化乙烯-乙酸乙烯共聚物/马来酸酐接枝聚丙烯(PP/EVAL/PP-g-MAH)动态硫化体系的力学性能、相形态、结晶性能和动态机械性能。结果表明:PP-g-MAH能显著改善PP/EVAL动态硫化体系的力学性能和熔体流动速率(MFR)。当PP/EVAL/PP-g-MAH质量比为80/20/8时,材料的冲击强度较不加PP-g-MAH时提高了179.6%,达到74.1 kJ/m2,MFR为13.4 g/10min。PP-g-MAH能有效改善分散相的分散效果和两相相容性,并同时促进PP/EVAL动态硫化体系中PP的α晶和β晶的形成。PP-g-MAH的加入使PP/EVAL动态硫化体系中PP组分的Tg向低温方向移动。     

Effects of compatibilizer on the layered silicate/ethylene vinyl acetate nanocomposite

Dispersion behavior of monmorillonite (MMT) is investigated in ethylene vinyl acetate (EVA)/MMT nanocomposite with various vinyl acetate content. Maleic anhydride (MAH) grafted polyethylenes with various MAH contents are used as a compatibilizer to enhance the dispersion of MMT. DMA and XRD studies indicate that an intercalated/exfoliated structure is obtained and vinyl acetate content and the concentration of PEMA play a critical role in EVA/MMT nanocomposite. Higher vinyl acetate content and concentration of grafted maleic anhydride result in better dispersion of MMT. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1057–1061, 2004     

EVA-g-MAH的制备及在聚合物共混相容中的应用

采用溶液接枝法合成得到乙烯-乙酸乙烯酯接枝马来酸酐聚合物（EVA-g-MAH）,利用核磁共振仪和红外光谱仪对产物进行分子链结构分析,结果表明：马来酸酐已成功接枝在EVA主链与酯基相连的叔碳原子上。通过调节马来酸酐（MAH）与EVA中乙酸乙烯酯（VA）单元的投料比,得到了不同接枝率（摩尔分数4.87%~12.3%）的产物。以EVA-g-MAH接枝共聚物为相容剂,通过聚合物加工制备了高密度聚乙烯（HDPE）/聚碳酸酯（PC）/EVA-g-MAH共混物,利用SEM对样品脆断面表面形貌进行对比观察,验证了EVA-g-MAH是HDPE/PC共混聚合物的良好相容剂。最后,研究了EVA-g-MAH对尼龙（PA6）/EVA共混物抗冲击强度的影响,当EVA-g-MAH加入质量分数为6%时对共混合金冲击强度提高最大。     

Nanostructure of EVA/organoclay nanocomposites: Effects of kinds of organoclays and grafting of maleic anhydride onto EVA

Nanostructure of poly(ethylene‐co‐vinyl acetate)/organically modified montmorillonite (MMT; EVA/organoclay) nanocomposites prepared by melt intercalation process was investigated using X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Three kinds of organoclays were used to see their influences on the nanostructure of the EVA hybrids. The effects of the polar interactions between the polymer and the silicate layers of organoclays were also investigated by grafting maleic anhydride onto EVA. It was found that the strong polar interactions between the polymer and the silicate layers of organoclays are critical to the formation of polymer‐layered silicate nanocomposites. The results also showed that increasing the mixing temperature was unfavorable to improve the dispersion of organoclays in the EVA matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1901–1909, 2003