996 resultados para EPM-g-GMA


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本课题是荷兰DSM公司委托研究课题,目的是在保留或基本保留怪尼龙46(PA46)的基本力学性能的情况下,降低PA46的成本,改善其吸水率高、尺寸稳定性差、电性能不好等缺点。有反应挤出法制备了甲基丙烯酸环氧丙酯(GMA)接枝的聚丙烯(PP-g-GMA)。化学滴定和红外光谱(FTIR)证明得到了PP-g-GMA产品。研究了引发剂、单体、反应温度、停留时间和助剂待因素对接枝率、接枝效率、熔体流动速率的影响。以苯乙烯作为助剂,接枝效率可以提高到80%。比较了PP-g-GMA与DSM公司提供的PP-g-GMA的力学性能。PP-g-GMA的抗张强度、杨氏模量、断裂伸长率和冲击强度都高于PP-g-MAH。研究并比较了PP-g-GMA和PP的热学性质。PP-g-GMA结晶度比PP增加,结晶温度提高,PP-g-GMA对Avrami方程有很大的偏差。制备了PA46/PP-g-GMA和PA46/PP共混物并对其力学性能、吸水率、形态结构、动态力学性质、热学性质等进行了研究。与PA46/PP相比,PA46/PP-g-GMA的抗张强度,杨氏模量,弯曲强度和弯曲模量都得到了提高。随着组成的变化,干态下PA46/PP-g-GMA的抗张强度分别比PA46/PP提高10%到35%,杨氏模量提高10%到30%,弯曲强度提高10%-200%,弯曲模量提高10%-50%。PA46/PP-g-GMA的吸水率大大低于PA46/PP,共混物组成为50/50时,PA46/PP的吸水率是PA46/PP-g-GMA的三倍多。扫描电镜(SEM)得到的PA46/PP及PA46/PP-g-GMA的拉伸和冲击断面形态显示,PP-g-GMA在PA46中的粒径尺寸大大变小,变均匀。动态热机械分析(DMA)、示差扫描量热仪(DSC),热失重分析(TGA)结果显示相同组分的PA/PP-g-GMA比PA46/PP的储能模量大,软化温度提高,组分为50/50时,PA46/PP-g-GMA比PA46/PP提高达120 ℃。在PA46/PP-g-GMA和PA46/PP共混体系中,由于两相之间的化学链接,使PP-g-GMA的熔融温度提高1-5 ℃,而PP的熔融温度降低1-7 ℃。相同组分的PA/PP-g-GMA和PA46/PP的热稳定性基本相同。

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以过氧化二异丙苯(DCP)为引发剂,甲基丙烯酸缩水甘油醋(GMA)为活性单体对HIPS进行熔融接枝,制得了功能化的高抗冲苯乙烯(HIPS-g-GMA)。比较HIPS-g-GMA和纯的HIPS的红外谱图,可以看到在HIPS-g-GMA的谱图上出现了一个新的吸收峰,即1730cm~(-1)处的C=O的伸缩振动吸收峰,它为接枝的GMA中的醋基基团的特征峰,因此可以确定GMA己经接枝到HIPS上。能谱分析也提供了相似的结论。同时研究了单体浓度和DCP用量对产物接枝率的影响。用化学滴定方法测定了接枝物的接枝率。随着GMA量的增加,接枝率也随之增加,当GMA用量超过14%时,接枝率趋于平缓;接枝率随DCP量增加而增加。采用DSC、SEM, WAXD, DMA及力学性能等方法和手段研究PBTIHIPS和PBT/HIPS-g-GMA二元共混体系的结晶、形态结构、动态力学性能及力学性能随组成的变化。当PBT为分散相,在增容体系中的PBT出现了分级结晶现象,结晶温度降低,这是由于分散相更为精细的结果。DMA结果表明,在PBTIHIP S-g-GMA体系中由于发生了化学反应,有接枝共聚物生成,体系中两个聚合物的Tg松弛均出现了较明显的降低,增容后体系的力学性能有显著提高。采用DSC, SEM, DMA及力学性能等方法和手段研究PBT/HIPS/HIPS-g-GMA三元共混体系的结构与性能。结果表明PBT无论是分散相还是连续相,HIPS-g-GMA的作用表现为:(1)对PBTIHIPS体系的熔融和结晶行为产生了明显的影响,使PBT的结晶速率变慢,结晶度降低,结晶尺寸分布变宽,结晶完善性变差;(2)改善了共混体系的相容性。未增容体系的形态结构为锐型界面,分散相粒子同基材相连接处清晰缝隙表明两组分间界面粘接很差,为典型的不相容两相形态结构;而加入功能化接枝物的体系的分散相粒子明显变小且分布均匀,甚至难以分辨两相结构的界面;(3)提高了体系的力学性能。在多官能团单体存在下,辐照对PBTIHIPS产生影响。(1)对共混体系的熔融和结晶行为产生影响,使共混体系中的PBT的熔点降低,熔程变宽,结品度下降,结晶速率变慢,结晶尺寸分布变宽,结晶完善性变差;(2)辐射引发多官能团单体反应,使体系的两个Tg松弛发生内移,表明体系的相容性得到改善;(3)当PBT为连续相时,辐射引发的多官能团单体反应对体系的形态结构影响不如化学增溶剂HIPS-g-GMA的效果显著,含有TMPTA的体系的形态结构要好于TAIL o当PBT为分散相,体系的形态结构变化很大,分散相尺寸明显变下小,且分布均匀;(4)辐射改性能提高PBT为分散相的共混体系的力学性能。利用DSC研究了不同成核剂对生物降解聚合物PHBV的结晶性能的彩响。结果表明:(1)添加的成核剂均能影响PHBV的结晶和熔融行为,提高PHBV的结晶速率和使PHBV的结晶更加完美;(2)所有的成核剂均能降低PHBV的结晶自由能;(3)成核剂对PHBV的影响依次为BN, talc, Tb_2O_3和La_2O_3。

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本工作用反应挤出接枝的方法,以甲基丙烯酸环氧丙醋和丙烯酸为单体,有机过氧化物为引发剂,对聚乙烯进行了宫能化。对文献中各种测定PE-g-GMA中GMA含量的方法进行了比较和改进,提出了一种操作较为简单可靠的方法米测定PE-g-GMA中GMA的含量。研究了单体、引发剂浓度、反应时间和反应温度对接枝率和凝胶含量的影响。引发剂浓度对交联反应的影响最大,存在一个引发剂浓度的临界值,超过这一数值,则聚乙烯熔融接枝会产生大量的凝胶。加入给电子试剂,如对-苯醌,亚磷酸三苯醋,四氯化碳等,可以使凝胶含量由17%降低到1%左右,而接枝率只有轻微的下降,由1%降低到0.8%。在低引发剂浓度和单体浓度的情况下,加入油酸可以使接枝率有显著的提高,由0.1提高到0.7%。在过氧化物引发剂中加入秋兰姆化合物,可以使自由基引发接枝反应和交联反应的程度降低,接枝率由1%降低到0.2%,熔体流动速率由0.2提高到8。而苯乙烯的加入可以使接枝率有明显的提高,由0.8%提高到1.4%。官能化聚乙烯的结晶速率随接枝率的增加而增加,但是其结晶熔融烩随接枝率的增加而降低。原因可能是接枝链既起到了成核剂的作用,又抑制了PE的结晶生长过程。对PBTILLDPE-g-AA共混物的力学性能研究表明,其断裂伸长率和冲击强度与PBTILLDPE相比有了明显提高,断裂伸长率最高可以提高5倍,非缺口冲击强度提高幅度也很大,当LLDPE-g-AA接枝率为1%时,样条未能冲断,而PBTILLDPE只有在组成为30170时才发生部分断裂,其余组分样品则完全发生脆性断裂。增容后的共混物的拉伸强度略有改善。这说明接枝到LLDPE上的AA中的竣基与PBT的端经基存在较为强烈的相互作用,使官能化的LLDPE与PBT的相容性得到了提高,从而使共混物的韧性得到了大幅度改善,强度和模量则略有改善。对共混物的形态观察表明,随共混物中LLDPE含量的增加,作为分散相 的LLDPE的粒子尺寸逐渐增加,尺寸分布也不均匀,而当共混物中加入LLDPE-g-AA后,作为分散相的LLDPE-g-AA的粒子尺寸与LLDPE相比减少了一半左右,尺寸分布也更加均匀。尽管加入LLDPE-g-AA使共混物的相容性得到改善,但当PBT作为连续相存在时,共混体系仍然表现为脆性断裂,只有当LLDPE为连续相时,共混物才表现为韧性断裂。增容后的共混物在裂纹引发区表现出塑性变形的特征,而在裂纹的不稳扩展区仍然为脆性断裂,说明相容性的改善主要是提高了共混物的裂纹引发能和稳定扩展能,因此共混物的非缺口冲击强度提高非常明显。另外在拉伸的情况下,相容性的改善使材料出现宏观的剪切屈服成颈的现象,从而使断裂能大幅度提高。加入LLDPE到PBT中,抑制了PBT的正常球晶的形成,使PBT球晶中正常球晶的含量降低,这种效应随LLDPE-g-AA中AA含量的增加而增加,而对总的结晶度的影响较小,说明共混物两组分之间的相互作用主要是使PBT的结晶形式受到影响。对官能化聚乙烯蠕变行为和动态流变行为的研究表明,官能化聚乙烯的零切粘度(3.9 * 10~4Pa.s)要高于纯聚乙烯(1.28 * 10~4Pa.s),其熔体弹性也有显著提高,这不仅是由于分子量增加造成的,而且对接枝率比较高的官能化聚乙烯,也存在长支链的影响。共混物的粘度与共混物组成的关系在低剪切应力的情况下,符合Utracki方程。高剪切应力条件下,共混物的形态沿毛细管径向位置不同发生改变导致Utracki方程失效。Utrackl方程中的表征界面滑移因子的参数刀不仅与剪切应力有关,而且与两组分的粘弹性有关。

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本工作合成了一种含异氰酸酷功能基团的不饱和单体,(3-异氰酸酯基-4-甲基)苯氨基甲酸-2-丙烯配(TAI)。以过氧化二异丙苯(OCP)为引发剂,该单体被用于乙烯丙烯共聚物(EPM)的自由基溶液接枝官能化。纯化后的接枝产物(EPM-g-TAI)的傅立叶变换红外光谱中存在2273cm-l异氰酸酷基团(-NCO),表明异氰酸醋单体已经接枝到乙丙共聚物上。接枝率采用化学滴定和红外光谱的方法确定。与EPM相比,EPM-g-TAl的分子量分布(MMO)变窄。采用旋转流变仪测定了EPM-g-TAl的流变行为。EPM-g-TAl的表观粘度高于EPM且随接枝率的增加而增加。采用接触角测定的表面分析表明,对于给定的的极性测定液体接枝产物的接触角随接枝率的增加而增大;我们同时得到接枝产物的表面自由能(75)以及表面自由能的色散分量(γs)和表面自由能的极性分量(γsρ),这些参数随接枝率提高而增大的趋势使我们可以定量估计接枝反应对改善极性的贡献。本工作研究了(3一异氰酸酯基-4-甲基)苯氨基甲酸-2-丙烯醋(TAl)官能化乙烯丙烯共聚物(EPM-g-TAI)与尼龙6(PA6)的反应共混。傅立叶变换红外光谱表明,由于EPM-g-TAl中的异氰酸醋基(-NCO)与尼龙6中的端胺基(-NH2)之间的化学反应:EPM-g-TAI/PA6谱图中3299cm-1处的阵日伸缩振动峰变窄变高,1640cm-1处阵日变形振动峰和1547cm-1处阵日弯曲振动峰变强。同时研究了共混体系的热性能、流变性能、机械性能和形态特征。OSC结果表明,在相同的共混组成下,EPM-g-TAI/PA6共混体系中尼龙6的结晶烩(△Hc)到氏于EPM/PA6共混体系中的尼龙6,这种差别随着共混物中乙烯丙烯共聚物含量的增加而增大,说明反应共混体系中尼龙6的结晶受到一定的限制;EPM-g-TAI/PA6共混体系的复数粘度和贮能模量高于相应的EPM/PA6共混体系;与相同组成的EPM/PA6相比,EPM-g-TAI/PA6中分散相的粒子尺寸更小,粒子分布更均匀,界面粘合更强;反应共混后的机械性能如拉伸强度、杨氏模量,弯曲强度和模量、缺口及非缺口冲击强度均随着接枝率的提高而增加。

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本文以过氧化物为引发剂,采用反应挤出的方法,制备了甲基丙烯酸缩水甘油酷官能化聚丙烯,采用化学滴定法和红外光谱法均证实了接枝共聚物的存在,并研究了反应条件对PP-g-GMA接枝率、接枝效率和熔体流动速率的影响,结果表明:1.当DCP含量一定时,随着单体含量的增加,接枝产物的接枝率出现了一个峰值。这表明一味地增加单体浓度未必有利于接枝率的提高;2.当GMA单体浓度一定时,PP-g-GMA的接枝率和熔融指数均随着引发剂含量的增加而逐渐增大,这表明引发剂浓度的增加在促进接枝反应的同时也引入了更多的副反应;3.助剂苯乙烯的加入大大地提高了PP-g-GMA的接枝率和接枝效率,且产物的熔融指数与纯聚丙烯相比变化很小,这表明助剂苯乙烯的加入有效地抑制了副反应的发生,且促进了接枝反应的发生。研究了官能化聚丙烯PP-g-GMA的形态、结构与性能,结果表明:1.官能化对聚丙烯的结晶行为有显著的影响,不仅结晶温度和熔融温度有显著的增加,而且结晶度也有一定程度的增加;2.纯聚丙烯的结晶结构为典型的a型结晶,而接枝聚丙烯的结晶则以a型结晶为主,并出现了少量的Y型结晶;3.采用Avrami方程可以很好的描述官能化聚丙烯的初级结晶行为,纯聚丙烯和官能化聚丙烯的 tl几和tmax均随着结晶温度的增加而增加,这表明它们的结晶过程由成核控制;4.采用Jeziornn法研究了官能化聚丙烯的非等温结晶动力学,非等温结晶过程可以分为初级结晶和次级结晶两部分,在次级结晶阶段,曲线偏离了初级结晶部分的直线,表明在次级结晶阶段,官能化聚丙烯的成核与生长方式发生了变化;5.采用DMA研究了官能化聚丙烯的动态热机械行为,官能化后聚丙烯的耐热性提高了,而且随着接枝率的升高,耐热性又有进一步的提高。以官能化聚丙烯作为反应型增容剂,采用反应共棍的方法,制备了耐油型全 硫化CNBR/PP热塑性弹性体,并研究了热塑性弹性体的形态、结构与性能。主要 结果如下:1.采用红外光谱法表征了梭基丁睛粉末橡胶和PP-g-GMA间的反应。 2.透射电子显微镜和原子力显微镜结果表明,当一部分聚丙烯被官能化聚丙烯替代后,体系中橡胶粒子的尺寸明显变小了,分布也更加均一了。在CNBR/PP-g-GMIA 体系中,原位增容反应形成的共聚物位于cNBR和PP-g-GMA两相的界面处。3.加入少量接枝聚丙烯后共混物的力学性能,如拉伸强度、100%定伸强度和断裂伸长 率均有明显的提高,而且,对于CNBR/PPPP-g-GMA共混物,只需少量的界面增 容剂便可以使两相界面达到饱和并达到较好的增容效果。4.动力学和热力学因素 均影响共混物中聚丙烯的结晶行为,在CNBR/PP体系中,动力学因素占主导地位,而CNBR/PP-g-GMA体系中热力学因素占主导作用。另外,采用Avromi方程描述了CNBR/PP和CNBR/PP-g-GMA体系的等温结晶动力学。5.接枝聚丙烯的加入阻碍了接枝聚丙烯与梭基丁睛橡胶两相间的界面层滑移,因此提高了体系的粘度。以官能化聚丙烯作为反应型增容剂,采用反应共混的方法,制备了耐油型全硫化NBR/PP热塑性弹性体,并研究了热塑性弹性体的形态、结构与性能。主要结果如下:1.采用红外光谱法表征了官能化聚丙烯与端氨基液体丁睛橡胶间的反应,但仅从红外光谱的结果很难断定产物的分子结构;2.采用透射电子显微镜观察了NBR/PP共混物的微观形态,结果表明,NBR/PP共混物体系中除了含有直径为几十纳米的小橡胶粒子外,还有直径为几微米甚至几十微米的大橡胶粒子存在,且随着橡胶含量的增加,体系中大橡胶粒子的数量增多了,小橡胶粒子的分布也变得密集了;3.采用差示扫描量热法表征了NB侧PP共混物的受限结晶行为,结果表明,(1)在220℃的高温下,部分丁睛橡胶分子产生了一定的运动,从而限制了聚丙烯分子的运动,使聚丙烯分子产生了受限结晶行为;(2)随着橡胶含量的增加,橡胶粒子间的距离逐渐变小,这使得位于橡胶粒子间隙的聚丙烯分子的运动受到限制,因此聚丙烯表现出受限结晶的行为;(3)受限的聚丙烯分子更倾向于Y型结晶。

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在引发剂过氧化二异丙苯(DCP)的作用下,通过添加少量界面增容剂苯乙烯(St)提高接枝率,使甲基丙烯酸缩水甘油酯(GMA)与(乙烯/丙烯/二烯)共聚物(EPDM)反应,得到接枝物EPDM-g-GMA,将EPDM-g-GMA与PET共混,以提高共混体系的冲击强度。探讨了不同含量的EPDM-g-GMA对共混体系力学性能的影响。结果表明,随着EPDM-g-GMA含量的增加,共混体系的缺口冲击强度显著提高,当其含量为50%时,材料的缺口冲击强度为344.9J/m,约为纯PET的12倍;拉伸强度、弯曲强度和弯曲弹性模量出现一定程度的下降;EPDM-g-GMA含量为20%~30%时,材料的综合力学性能较好。

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Reactive compatibilization of ethylene-propylene copolymer functionalized with allyl (3-isocyanato-4-tolyl) carbamate (TAI) isocyanate (EPM-g-TAI) and polyamide 6 (PA6) was investigated in this paper, FTIR analysis revealed the evidence of a chemical reaction between the end groups of PA6 and EPM-g-TAI. Thermal, rheological, morphological, and mechanical properties of the resultant system were examined, DSC analysis indicated that the crystallization of PA6 in Pa6/EPM-g-TAI blends was inhibited, due to the chemical reaction that occurs at the interface of PA6 and EPM-g-TAI. Rheological measurement showed that complex viscosity and storage modulus of PA6/EPM-g-TAI were both dramatically enhanced compared to those of PA6/EPM at the same blending composition. After examining the morphology of both blending systems, smaller particile sizes, more homogeneous distribution of domains and improved interfacial adhesion between matrix and domains were observed in the compatibilized system. Mechanical properties such as tensile strength. Young's modulus, flexural strength and modulus, as well as notched and un-notched impact strength of PA6/EPM-g-TAI blends were also found to improve gradually with increasing the content of grafted TAI.

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An ethylene-propylene copolymer (EPM) was functionalized with an iso cyanate-bearing unsaturated monomer, allyl(3-isocyanate-4-tolyl) carbamate (TAI), with dicumyl peroxide as an initiator in a xylene solution. Fourier transform infrared (FTIR) was used to confirm the formation of EPM-g-TAI. The peak at 2273 cm(-1), characteristic of -NCO groups in EPM-g-TAI, revealed evidence of grafting. The grafting degree was determined with both chemical titration and FTIR. The grafting degree could be adjusted, and the maximum was over 6 wt % without any gelation. The molar mass distribution of EPM-g-TAI was narrower than that of EPM. The rheological behavior of both EPM-g-TAI and EPM was investigated with a rotational rheometer. The apparent viscosity of EPM-g-TAI was higher than that of EPM and increased with an increasing grafting degree of TAI. Surface analysis by contact-angle measurements showed that contact angles of EPM-g-TAI samples to a given polar liquid decreased with an increasing grafting degree of TAI. We also obtained the dispersion component of the surface free energy (gamma(S)(d)), the polar component of the surface free energy (gamma(S)(d)), and the total surface free energy (gamma(S) = gamma(S)(d) + gamma(S)(p)) of the grafted EPM. These parameters increased with the enhancement of the grafting degree, which gave us a quantitative estimation of the polar contribution of the grafted TAI to the total surface free energy of EPM-g-TAI.

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将具有纳米尺度的全交联型羧基丁腈粉末橡胶 ( CNBR)与聚丙烯 ( PP)及用甲基丙烯酸环氧丙酯( GMA)官能化的聚丙烯 ( PP-g-GMA)进行反应共混 ,制备了一种新型 CNBR/PP热塑性弹性体 .用原子力显微镜 ( AFM)和透射电子显微镜 ( TEM)研究了 CNBR/PP热塑性弹性体的形态 ,加入 PP-g-GMA增容剂后 ,CNBR分散相的粒子尺寸显著降低 ,分布也趋于均一 .与未增容体系相比 ,增容体系的拉伸强度和断裂伸长率均有大幅度的改善 ,如 CNBR含量为 75 %时 ,拉伸强度提高了 94% ,断裂伸长率增加了 1 3 6% .用差示扫描量热法 ( DSC)研究了热塑性弹性体中聚丙烯的结晶行为 ,在增容体系中 ,共混前后聚丙烯的结晶温度提高了 1 0℃ ,表明橡胶粒子或两相界面处形成的反应产物起到了类似成核剂的作用.

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以过氧化二异丙苯 (DCP)为引发剂 ,甲基丙烯酸缩水甘油酯 (GMA)为活性单体 ,高抗冲苯乙烯(HIPS)通过熔融接枝制得了功能化的高抗冲聚苯乙烯接枝物 (HIPS g GMA)。用红外光谱和电子能谱对其结构进行了表征。HIPS g GMA的红外谱图 ,证明GMA已经接枝到HIPS上。电子能谱分析也提供了相似的结论。研究了单体浓度和DCP用量对产物接枝率的影响 ,并用化学滴定方法测定了接枝物的接枝率。用DSC、SEM、WAXD、DMA等研究了PBT/HIPS和PBT/HIPS g GMA的结晶、形态结构、动态力学性能及力学性能随组成的变化。SEM及DMA分析表明增容后体系的相容性得到改善 ,力学性能有较大提高。

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利用毛细管流变仪研究了官能化LLDPE(LLDPE g AA、LLDPE g GMA)的流变行为。结果表明 :在高的剪切应力下LLDPE g AA、LLDPE g GMA的表观粘度比纯LLDPE的小。表明官能化LLDPE的流动性提高了 ,其加工性能变好。官能化LLDPE的表观粘度随接枝单体含量的增加而降低 ,这说明接枝到LLDPE分子链上的单体起到了内润滑剂的作用。利用Instron 112 1拉力机测试了官能化LLDPE的力学性能。结果表明 ,其拉伸强度 ,杨氏模量和断裂伸长率与纯LLDPE相比没有明显的变化。

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The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP main chains and used instead of plain PP. Several technological characterizations were performed here on their interfaces. ESCA was used to confirm that some kind of reaction occurred between end groups of PA1010 and epoxy species of PP-g-GMA. The peel test was adopted to measure interfacial adhesion. It was found that the fracture energy of interfaces between PA1010 and PP-g-GMA was dramatically increased with the content of GMA. Their interfaces were observed as being blurred by using SEM and TEM and a crack that could be seen in the case of the interfaces of the PA1010 and the plain PP disappeared.

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Binary blends of polyamide 1010/poly(propylene) and polyamide 1010 (PA1010)/poly(propylene)-graft-(glycidyl methacrylate) (PP-g-GMA) were prepared. The epoxy groups in PP-g-GMA react with the amino end-groups in PA1010, thus a PA1010-graft-PP copolymer is formed and acts as a compatibilizer between PA1010 and PP-g-GMA. The reaction was confirmed by electron spectroscopy for chemical analysis (ESCA) and attenuated total reflection (ATR)-FTIR spectroscopic analysis, and also evaluated by the stability of the suspension obtained by dissolving the blends in formic acid and by the morphologies of the blends.

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Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the morphology of blends of PA1010 and polypropylene (PP) compatibilized with polypropylene grafted with glycidyl methacrylate (PP-g-GMA). It is found that the morphologies are dependent on the content of glycidyl methacrylate in PP-g-GMA and the mixing time. The size of the dispersed PP particles decreases as the content of GMA in the PP-g-GMA increases for binary blends of PA1010 and PP-g-GMA. Similar results are obtained for changing the mixing time. Ternary blends of PA1010, PP, and PP-g-GMA indicate that morphologies depend on the content of glycidyl metyacrylate in the PP-g-GMA and the miscibility of PP and PP-g-GMA. By changing the content of GMA in PP-g-GMA, it was possible to introduce significant changes of morphology. A matrix removal TEM method is used to investigate the interfacial structure of PA1010/PP blends containing PP-g-GMA as a compatibilizer. This technique shows the reaction product between PA1010 and PP-g-GMA to be located at interface as a surrounding layer around domain particles. SEM observation on the interface shows that the adhesion between PA1010 and pure PP is very weak and their interface boundary is sharp. For the samples of PA1010 and PP-g-GMA, it was found that the interface was not so obvious, and the reaction between PA1010 and PP-g-GMA strengthens the interface significantly. (C) 1997 Elsevier Science Ltd.

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Polyamide 1010/poly(propylene) (PA1010/PP) blends were investigated with and without the addition of poly(propylene)-graft-glycidyl methacrylate (PP-g-GMA). The effect of the compatibilizer on the thermal properties and crystallization behavior was determined by differential scanning calorimetry and wide-angle X-ray diffraction. From the results it is found that the crystallization of PA 1010 is significantly affected by the presence of PP-g-GMA. PP/PA 1010 (75/25) blends containing higher amounts of PP-g-GMA show concurrent crystallization at the crystallization temperature of PP. Isothermal crystallization kinetics also were performed in order to investigate the influence of the compatibilized process on the nucleation and growth mechanism. In the PP/PA 1010 (25/75) blends, concurrent crystallization behavior was not observed, even though the amount of PPg-GMA was high.