PP固相接枝马来酸酐增容PP／PA6研究

以高速搅拌器为反应器,利用聚丙烯(PP)粉料自身摩擦生热,制备出不同接枝率的聚丙烯固相接枝马来酸酐(PP-g-MAH);通过对熔体流动速率测定、差热分析以及偏光显微分析,研究了PP-gMAH对PP／聚酰胺6(PA6)共混体系的增容作用及其对共混体系力学性能的影响。结果表明:采用固相法制备的PP-g-MAH可以明显提高PP与 PA6的相容性,PP-g-MAH接枝率高(1．2％)增容效果好;添加固相接枝PP-g-MAH的PP／PA6共混体系的拉伸强度和冲击强度高于添加熔融接枝物的PP／PA6共混体系。     

OMMT对PA1212/PP共混物形态结构与力学性能的影响

通过熔融挤出法制备了尼龙1212 (PA1212)/聚丙烯(PP)(质量比70/30)/有机蒙脱土(OMMT)共混物.采用广角X射线衍射(WAXD)、扫描电子显微镜(SEM)等研究了OMMT在PA1212/PP共混物中的分布状态及其对PA1212/PP共混物形态结构与力学性能的影响.结果表明:在PA1212/PP/OMMT共混体系中,OMMT用量较低时,主要为剥离形态分布,当OMMT用量为7 phr时,OMMT片层主要为插层结构;随OMMT用量的增加,PP分散相尺寸逐渐减小,PA1212/PP/OMMT共混体系的强度逐渐提高,缺口冲击强度呈下降趋势.     

ABS/PA6/OMMT共混体系的结晶及热力学性能

采用丙烯腈-丁二烯-苯乙烯共聚物(ABS)、尼龙6(PA6)和有机蒙脱土(OMMT)通过熔融共混的方法制备了ABS/PA6合金。利用广角X射线衍射(WAXD)、透射电子显微镜(TEM)、差示扫描量热法(DSC)、动态热力学分析仪(DMA)研究了ABS/PA6/OMMT合金体系的结晶性能、热力学性能及OMMT在共混体系中的分布情况。结果表明,OMMT以剥离状态分布于PA6相中,PA6、ABS两相界面存在少量的OMMT片层。OMMT的加入降低了合金体系的结晶温度及结晶度,且对ABS/PA6共混体系具有一定的增容作用。添加3份OMMT到ABS/PA6体系中,其储能模量达到极值,ABS/PA6/OMMT共混体系的玻璃化转变温度变化较小。     

ABS/OMMT、PA6/OMMT复合材料形态及性能

熔融挤出制备了有机蒙脱土(OMMT)含量不同的ABS/OMMT,PA6/OMMT复合材料,用X射线衍射仪(XRD)、透射电子显微镜(TEM)等仪器研究OMMT分别在ABS、PA6基体中的分布情况及对其力学性能的影响.结果表明:在ABS/OMMT复合材料中,OMMT主要为插层结构,大部分OMMT片层以聚集状态存在;而对PA6/OMMT复合材料,OMMT片层主要以剥离形态分布在PA6基体相中;随着OMMT含量增加,ABS/OMMT复合材料的拉伸、弯曲强度及弯曲模量都先上升后下降,且当OMMT含量在3份时性能较好,其缺口冲击强度呈下降趋势;PA6/OMMT复合材料在OMMT含量为3份时,其拉伸、弯曲强度和弯曲模量都出现极值现象,而缺口冲击强度线性降低.由于OMMT与PA6有较好的亲和力,在PA6中分散性较好,使PA6/OMMT复合材料的综合力学性能比ABS/OMMT复合材料的优异.     

接枝聚丙烯增容改性PP/PA合金性能的研究

用PP接枝物增容PP/PA6共混体系,观察分析了共混合金的形态结构特点,测试了共混物的力学性能.结果表明：单独加入PP-g-MAH,力学性能均呈现先升后降的趋势,峰值时拉伸强度比未加接枝物时可提高20%,弯曲强度比未加接枝物时提高了54%,冲击强度比不添加接枝物时提高了3.6%.添加PP-g-MAH对不同比例PP/PA6共混物力学性能的影响不同,固定PP-g-MAH用量为4%,PA6质量分数为30%时共混物的综合力学性能达到最好.用PP-g-MAH和PP-g-GMA两种接枝物共同作为相容剂加入到PP/PA6共混物中比单独使用一种的效果要好,拉伸、弯曲和冲击强度都得到显著的提高.由共混物的SEM照片可以看到,PP-g-MAH使分散相的粒径变小,分布均匀,界面相互作用加强,所以是PP/PA6共混物的有效增容剂.     

有机蒙脱土对PA66/PP合金的增容作用研究

研究考察了有机蒙脱土对PA66/PP合金的增容作用。结果表明:在PA66/PP体系中OMMT可以起到减小PP分散相粒径的作用,但需3%以上的添加量才可达到明显的效果,而相容剂的进一步添加可使PP粒径急剧变小,粒径分布变窄;加工方法可以对OMMT复合体系中PP分散相粒径产生一定的影响,但不改变OMMT增容作用的规律;在复合体系中,较多的OMMT倾向于分布在PP分散相粒子周围,而有效地阻止分散相粒子凝集。     

剪切作用下POE-g-MAH和PP-g-MAH对PA1010/PP共混物的增容作用

采用熔融共混的方法制备了聚酰胺1010/聚丙烯（PA1010/PP）共混物,通过扫描电镜、力学性能和差示扫描量热等方法研究了剪切作用下马来酸酐接枝乙烯-辛烯共聚物（POE-g-MAH）和马来酸酐接枝聚丙烯（PP-g-MAH）对PA1010/PP共混物的增容作用。结果表明,同样条件下,PP-g-MAH增容体系的相区尺寸较小,相界面更模糊,PP相的结晶温度和结晶度明显提高,共混物的拉伸强度和冲击强度均高于非增容体系。而POE-g-MAH增容体系的相区尺寸相对较大,PP相的结晶温度和结晶度明显降低,共混物只有冲击强度明显高于非增容体系,拉伸强度略低于非增容体系。     

纳米蒙脱土对PA66/PP共混物结构与性能的影响!

通过融挤出制备了PA66/PP/纳米蒙脱土(OMMT)共混物,采用广角X射线衍射(WAXD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等研究了OMMT在PA66/PP共混物中的分散及其对PA66/PP共混物力学性能、结构的影响。结果表明,OMMT主要为剥离状态分布于PA66/PP中。随OMMT含量增加,PP分散相尺寸逐渐减小,且5 phr OMMT时,PP分散相尺寸达到最小。PA66/PP/OMMT共混物的拉伸强度和模量呈上升趋势,缺口冲击强度下降。     

OMMT对PA6/ABS共混体系结晶行为及热力学性能的影响

采用有机蒙脱土(OMMT)、聚酰胺6(PA6)和丙烯腈-丁二烯-苯乙烯共聚物(ABS),通过熔融共混的方法制备了PA6/ABS/OMMT共混物。利用透射电子显微镜(TEM)、差示扫描量热仪(DSC)及动态热力学分析仪(DMA)研究了OMMT在PA6/ABS(70/30)合金体系中的分布和分散状况,以及PA6/ABS/OMMT共混体系的结晶行为和热力学性能。结果表明:OMMT片层主要分散于PA6相中,PA6与ABS的两相界面处亦存在少量OMMT片层。OMMT的加入降低了PA6/ABS共混体系的结晶温度,使PA6的结晶结构发生改变,说明OMMT具有一定的增容作用。引入OMMT后,PA6/ABS共混体系的储能模量有所提升,玻璃化转变温度则变化较小。     

PP/PA6/OMMT复合材料力学性能与结晶性能的研究

采用3种不同有机改性过的蒙脱土(牌号为DK2,DK3,DK5)熔融插层法制备了PP/PA6/OMMT纳米复合物材料,在此基础上使用1%～7%的DK2的蒙脱土再次制备PP/PA6/OMMT纳米复合物材料,借助力学性能测试和差示扫描量热法(DSC)对体系的力学性能和结晶性能进行了研究。结果表明:使用DK2制备的复合材料的力学性能优于使用DK3和DK5制备的复合材料的力学性能;相对于纯PP,PP/PA6/OMMT纳米复合物材料随OMMT含量的增加,拉伸强度和弯曲强度是先增加后降低,最大下降幅度分别为8.7%和5.3%;冲击韧性一直上升达到9.61kJ/m2。OMMT的加入,对PP/PA6有异相成核的作用,提高PP/PA6的结晶速率和结晶度。     

Solid‐state mechanical properties of polypropylene/nylon 6/clay nanocomposites

The mechanical and thermomechanical properties as well as microstructures of polypropylene/nylon 6/clay nanocomposites prepared by varying the loading of PP‐MA compatibilizer and organoclay (OMMT) were investigated. The compatibilizer PP‐MA was used to improve the adhesion between the phases of polymers and the dispersion of OMMT in polymer matrix. Improvement of interfacial adhesion between the PP and PA6 phases occurred after the addition of PP‐MA as confirmed by SEM micrographs. Moreover, as shown by the DSC thermograms and XRD results, the degree of crystallinity of PA6 decreased in the presence of PP‐MA. The presence of OMMT increased the tensile modulus as a function of OMMT loading due to the good dispersion of OMMT in the matrix. The insertion of polymer chains between clay platelets was verified by both XRD and TEM techniques. The viscosity of the nanocomposites decreased as PP‐MA loading increased due to the change in sizes of PA6 dispersed phase, and the viscosity increased as OMMT loading increased due to the interaction between the clay platelets and polymer chains. The clay platelets were located at the interface between PP and PA6 as confirmed by both SEM and TEM. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Effect of clay modification on the morphological,mechanical, and thermal properties of polyamide 6/polypropylene/montmorillonite nanocomposites

Polyamide 6/polypropylene (PA6/PP = 70/30 parts) blends containing 4 phr (parts per hundred resin) of organophilic montmorillonite (OMMT) were prepared by melt compounding. The sodium montmorillonite (Na‐MMT) was modified using three different types of alkyl ammonium salts, namely dodecylamine, 12‐aminolauric acid, and stearylamine. The effect of clay modification on the morphological and mechanical properties of PA6/PP nanocomposites was investigated using x‐ray diffraction (XRD), transmission electron microscopy (TEM), tensile, flexural, and impact tests. The thermal properties of PA6/PP nanocomposites were characterized using thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), and heat distortion temperature (HDT). XRD and TEM results indicated the formation of exfoliated structure for the PA6/PP nanocomposites prepared using stearylamine modified montmorillonite. On the other hand, a mixture of intercalated and exfoliated structures was found for the PA6/PP nanocomposites prepared using 12‐aminolauric acid and dodecylamine modified montmorillonite. Incorporation of OMMT increased the stiffness but decreased the ductility and toughness of PA6/PP blend. The PA6/PP nanocomposite containing stearylamine modified montmorillonite showed the highest tensile, flexural, and thermal properties among all nanocomposites. This could be attributed to better exfoliated structure in the PA6/PP nanocomposite containing stearylamine modified montmorillonite. The storage modulus and HDT of PA6/PP blend were increased significantly with the incorporation of both Na‐MMT and OMMT. The highest value in both storage modulus and HDT was found in the PA6/PP nanocomposite containing stearylamine modified montmorillonite due to its better exfoliated structure. POLYM. COMPOS., 31:1156–1167, 2010. © 2009 Society of Plastics Engineers     

Effect of added ionomer on morphology and properties of PP/organoclay nanocomposites

Ethylene-methacrylic acid ionomer (Surlyn) with concentration up to 20 wt% based on total weight of polymer resin was added into polypropylene (PP)/organoclay hybrids. The microstructure, rheological properties, crystallization properties and mechanical properties of the obtained nanocomposites have been investigated. The addition of ionomer markedly enlarged interlayer spacing of the platelets and led to an improved degree of exfoliation. Moreover, clay silicates were found to selectively disperse either inside the ionomer phase or at the phase boundary. Compared to the binary immiscible blends, an improved interfacial adhesion was achieved for PP/Surlyn/OMMT hybrids. Unlike PP/Surlyn binary blends, the viscoelastic properties of the hybrids significantly increased with increasing Surlyn concentration, which could be attributed to the improved clay dispersion and the contribution of silicate layers at the interface between PP and Surlyn. A synergistic role between Surlyn and clay was also found to suppress the crystallization of PP matrix. In addition, PP/Surlyn/OMMT hybrids exhibited superior tensile strain compared to the corresponding PP/PP-g-MA/OMMT. Both tensile strength and elongation at break showed maximum at Surlyn concentration of 5 wt%. By comparing the experimental tensile yield strength with model prediction, it was suggested that the clay platelets localized at the interface could play a role of interfacial activation to some extent.     

Study on the microstructures and mechanical behaviour of compatibilized polypropylene/polyamide‐6 blends

A series of blends of polypropylene (PP)–polyamide‐6 (PA6) with either reactive polyethylene–octene elastomer (POE) grafted with maleic anhydride (POE‐g‐MA) or with maleated PP (PP‐g‐MA) as compatibilizers were prepared. The microstructures and mechanical properties of the blends were investigated by means of tensile and impact testing and by scanning electron microscopy and transmission electron microscopy. The results indicated that the miscibility of PP–PA6 blends was improved with the addition of POE‐g‐MA and PP‐g‐MA. For the PP/PA6/POE‐g‐MA system, an elastic interfacial POE layer was formed around PA6 particles and the dispersed POE phases were also observed in the PP matrix. Its Izod impact strength was four times that of pure PP matrix, whilst the tensile strength and Young's modulus were almost unchanged. The greatest tensile strength was obtained for PP/PA6/PP‐g‐MA blend, but its Izod impact strength was reduced in comparison with the pure PP matrix. © 2002 Society of Chemical Industry     

Influences of component ratio of minor phases and charge sequence on the morphology and mechanical properties of PP/PS/PA6 ternary blends

In this study, influences of both component ratio of minor phases and charge sequence on the morphology and mechanical performance in typical ternary blends, polypropylene (PP)/polystyrene (PS)/polyamide-6 (PA6), have been studied. Reactive compatibilization of the blends has been carried out using multi-monomer melt grafted PP with anhydride groups and styrene segments. For uncompatibilized blends, scanning electron microscope (SEM) and selective solvent extraction showed that the blends presented a core–shell morphology with PS as shell and PA6 as core in the PP matrix, in spite of the component ratio and charge sequence. The shell thickened and droplet size decreased with increasing the PS/PA6 component ratio. While for compatibilized blends, the addition of compatibilizers resulted in a significant reduction of the dispersed droplet size and the phase structure of the dispersed phases was greatly dependent on the charge sequence. When the blending of PA6, g-PP, and PP are preceded, the encapsulation structure reversed into the structure of PS phase encapsulated by PA6 phase, which led to better tensile and flexural strength of the blends.     

Structural analysis of multicomponent nanoclay-containing polymer blends through simple model systems

A systematic approach was adopted to study multicomponent clay-containing nanocomposites using compatibilized and non-compatibilized blends of polyamide 6 (PA6)/acrylonitrile-butadiene-styrene terpolymer (ABS) and their organoclay (OMMT) nanocomposites. For this purpose PA6/styrene-acrylonitrile copolymer (SAN) based blends and nanocomposites were selected as simple model systems. In this way the role of each component of the systems, especially the clay, compatibilizer, and polybutadiene fraction on the formation of intercalated or exfoliated OMMT structures as well as resulting dynamic mechanical properties (DMA) could be elucidated. Structural analysis of the model systems using theoretical approach, and X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and DMA revealed that the most crucial factor in controlling the morphology and achieving different levels of dispersion is the extent of interaction between clay and the polymer matrix. Morphological analysis revealed that the OMMT layers were dispersed and exfoliated largely in the PA6 phase but, some were also accumulated at the rubber particle surface which remained non-intercalated. The effect of a compatibilizer on the dispersion of OMMT was not completely clear. The SAN based nanocomposites containing PA6 showed fully exfoliated OMMT structures, whereas the ABS based nanocomposites, having an additional rubber fraction, showed a mixed exfoliated and also partly non-intercalated morphology. The OMMT did not change the general occurrence of the co-continuous structures but refined the structures and led to mechanical stiffening as indicated by the DMA results. A correlation was established between the changes in the morphological states and the DMA properties.     

PP-g-(MAH/VAc)接枝物对PP/PA6体系的增容作用

通过扫描电镜、差示扫描量热仪和力学性能测试等方法研究了聚丙烯接枝马来酸配和酷酸乙烯酷(PP-g-MAH/VAc)对聚丙烯康酸胺6(80/20}共混体系的增容效果。结果表明,PP-g-(MAH/DAc)用于PP/PA6共混体系,分散相PA6的微区尺寸可以减小到5μm以下,相应地提高了共混物的断裂伸长率、拉伸强度和冲击强度。使用接枝率为5.3%的PP-g-(MAH/VAc)作为相容剂,当用量为8%时,体系的拉伸强度为60.88MPa,断裂伸长率为558%,冲击强度为5.28KJ/㎡.DSC分析表明,PP/PA6共混体系各组分相互促进成核,结晶度降低。FTIR结果表明,PP-g-(MAH/VAc)中的MAH上的酸配基团与PA6中的酸胺键发生了化学反应从而改善了体系的相容性。     

Synthesis of exfoliated polyamide 6,6/organically modified montmorillonite nanocomposites by in situ interfacial polymerization

Polyamide 6,6 (PA 6,6)/organically modified montmorillonite (OMMT) nanocomposites were prepared by a novel method, using direct interfacial polymerization of an aqueous hexamethylene diamine and a nonaqueous adipoyl chloride in dichloromethane solution containing different amounts of OMMT dispersed nanoparticles. The state of dispersion of OMMT in the PA 6,6 matrix was investigated by means of X‐ray diffraction, as well as transmission electronic microscopy. The results indicated that the OMMT nanoparticles were dispersed homogeneously and nearly exfoliated in the PA 6,6 matrix. The random arrangement of clay platelets in the PA 6,6 matrix, exfoliation, and intercalation of clays between the PA 6,6 matrix were distinguished. The amount of the incorporated OMMT in the PA 6,6 matrix was determined by means of TGA technique. Furthermore it was found that addition of a small amount of OMMT dramatically improved the thermal stability of PA 6,6. The TGA thermograms of all the synthesized nanocomposite samples showed an interesting unexpected lag in the weight loss at high temperatures, which could be another evidence for formation of fully exfoliated nanocomposites structures, with improved thermal stability. Nucleating effect of the OMMT nanoparticles and their influence on crystallization behavior of PA 6,6 was confirmed by DSC. Finally it is concluded that the in situ interfacial polycondensation is a suitable method for synthesis of nanocomposites with well dispersed structures and enhanced properties. POLYM. COMPOS., 28:733–738, 2007. © 2007 Society of Plastics Engineers     

Phase morphology evolution and compatibilization of immiscible polyamide 6/polystyrene blends using nano‐montmorillonite

Nanocomposites of organic nano‐montmorillonite (nano‐OMMT)‐filled immiscible polyamide 6 (PA6)/polystyrene (PS) blends were prepared by three different processing methods. Masterbatch M1 of OMMT/PA6 and masterbatch M2 of OMMT/PS were prepared as separate masterbatchs by melt mixing with PA6 or PS, and then either mixed together or each mixed individually with appropriate amounts of PS or PA6, respectively. The effects of nano‐OMMT content and processing method on the structure, phase morphology, and mechanical properties of the PA6/PS/OMMT nanocomposites were investigated by X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, and mechanical properties tests. The results showed that the nano‐OMMT by M1 and M2 masterbatches dispersed primarily as exfoliated platelets in the PA6 matrix in the final composites regardless of the method of preparation. A drastic decrease of dispersed PS phase size and a very homogeneous size distribution were observed with the addition of nano‐OMMT. The PA6/PS/OMMT nanocomposites prepared from the M2 displayed the smallest dispersed PS phase size and best distribution of OMMT. The improvement of the mechanical properties of the PA6/PS/OMMT nanocomposites was attributed to the enhanced compatibilization of the immiscible PA6/PS blends by using nano‐OMMT. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers     

Morphology and properties of nylon 6 and high density polyethylene blends in presence of nanoclay and PE‐g‐MA

In this study, we report the synergistic effect of nanoclay and maleic anhydride grafted polyethylene (PE‐g‐MA) on the morphology and properties of (80/20 w/w) nylon 6/high density polyethylene (HDPE) blend. Polymer blend nanocomposites containing nanoclay with and without compatibilizer (PE‐g‐MA) were prepared by melt mixing, and their morphologies and structures were examined with scanning electron microscopy (SEM) and wide angle X‐ray diffractometer (WAXD) study. The size of phase‐separated domains decreased considerably with increasing content of nanoclay and PE‐g‐MA. WAXD study and transmission electron microscopy (TEM) revealed the presence of exfoliated clay platelets in nylon 6 matrix, as well as, at the interface of the (80/20 w/w) nylon 6/HDPE blend–clay nanocomposites. Addition of PE‐g‐MA in the blend–clay nanocomposites enhanced the exfoliation of clays in nylon 6 matrix and especially at the interface. Thus, exfoliated clay platelets in nylon 6 matrix effectively restricted the coalescence of dispersed HDPE domains while PE‐g‐MA improved the adhesion between the phases at the interface. The use of compatibilizer and nanoclay in polymer blends may lead to a high performance material which combines the advantages of compatibilized polymer blends and the merits of polymer nanocomposites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012