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PA6/PP/SEBS-g-MAH共混物的相容性研究 总被引:2,自引:1,他引:2
采用马来酸酐接枝(氢化苯乙烯/丁二烯/苯乙烯)共聚物(SEBS-g-MAH)作为增容剂,研究了增容剂用量对尼龙6/聚丙烯(PA6/PP)共混体系相态结构、力学性能的影响,以及在相同增容剂用量下不同PA6、PP配比对体系相形态的影响。结果表明,SEBS-g-MAH中的酸酐基团能与PA6末端的氨基发生化学反应,在PA6和PP的内表面形成PA6-SEBS接枝共聚物,明显改善了两相的界面相容性,并使共混物的力学性能得到显著提高。共混物冲击断面形貌的分析表明,共混物发生了明显的脆韧转变。 相似文献
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邓云娇;刘振国;孙树林;杨海东;张会轩 《中国塑料》2011,26(12):31-34
采用乳液聚合法制备了一系列马来酸酐(MAH)官能化的丙烯酸丁酯橡胶(PBA)与苯乙烯(St)及丙烯腈(AN)的接枝共聚物(PBA-g-SAN)核壳结构改性剂(ASA-g-MAH),用于聚酰胺6(PA6)的增韧。Molau实验证实了PA6/ASA-g-MAH共混体系中存在化学反应,考察了MAH含量对共混体系结构和性能的影响。结果表明,随着MAH含量的增加,PA6/ ASA-g-MAH共混物的冲击强度逐渐增大,当MAH含量为4 %(质量分数,下同)时材料冲击强度达到1008 J/m;与PA6/ASA共混物相比,PA6/ASA-g-MAH共混物具有较高的拉伸强度和断裂伸长率;随着MAH含量的增加,ASA- g-MAH在PA6基体中的分散程度越来越好,当MAH含量达到4 %以上时,无聚集现象发生;ASA-g-MAH中橡胶粒子的空洞化和PA6基体的剪切屈服是主要的增韧机理。 相似文献
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采用马来酸酐接枝氢化苯乙烯-丁二烯嵌段共聚物(SEBS-g-MA)改性聚苯乙烯(PS)/尼龙6(PA6)共混物。SEM观察共混物相态发现,随着SEBS-g-MA加入量的增加,PS/PA6双连续相结构并未改变,而PS和PA6的相畴尺寸逐渐变小,加入量超过10%以后,相畴尺寸出现变大的趋势。动态流变测试表明,PS/PA6共混物熔体的复数粘度、储能模量及损耗模量均随SEBS-g-MA的加入而增加,即SEBS-g-MA同时提高了体系的粘性和弹性,但是体系的粘弹比却出现下降,且随加入量的增多,作用程度更为显著。 相似文献
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转矩流变仪中熔融法制备了苯乙烯(St)和甲基丙烯酸缩水甘油酯(GMA)或甲基丙烯酸羟乙酯(HEMA)分别接枝乙烯-辛烯共聚物(POE),并将接枝物用于聚酰胺6(PA6)增韧改性.结果表明:2种接枝物POE-g-(GMA-co-St)和POE-g-(HEMA-co-St)的最佳反应加工时间分别为8.0 min和10.0 min,二者均能明显改善PA6与POE之间的相容性,但是前者增韧效果更好,其改性共混物力学性能更优. 相似文献
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SAN—g—GMA的制备及其在PA6/ABS中的应用 总被引:2,自引:0,他引:2
采用固相接枝制备苯乙烯/丙烯腈共聚物接枝甲基丙烯酸缩水甘油酯(SAN-g-GMA),研究了过氧化苯甲酰(BPO)和GMA用量对接枝吸光比的影响,以自制的SAN-g-GMA增容尼龙6/丙烯腈-丁二烯-苯乙烯(PA6/ABS)共混物,探讨了SAN-g-GMA对共混物结构与性能的影响.结果表明:SAN-g-GMA能够增容PA6/ABS共混物,改善共混物的力学性能;Molau实验发现,SAN-g-GMA能够促进PA6/ABS两相界面结合,起到相容作用;共混物的SEM照片表明,SAN-g-GMA使ABS在PA6中分散均匀,粒子尺寸减小. 相似文献
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接枝率对PVC/PA6-g-SMA共混物结构与性能的影响 总被引:2,自引:0,他引:2
王彩红;周秉正;何敏;鲁圣军;于杰 《中国塑料》2009,23(3):37-40
采用熔融共混方法制备了聚氯乙烯(PVC)与不同接枝率苯乙烯-马来酸酐共聚物(SMA)接枝改性聚酰胺6(PA6-g-SMA)的共混物,研究了PA6-g-SMA接枝率对PVC/PA6-g-SMA共混物力学性能及凝聚态结构的影响。结果表明,接枝率越高,PA6-g-SMA与PVC的相容性越好,在PVC基体中能以更小的相畴均匀分散,对PVC的增韧增强作用越明显;当PA6-g-SMA的接枝率为5.12 %,添加量为15 %(质量分数,下同)时,共混物的冲击强度为64.7 kJ/m2,拉伸强度为55 MPa。 相似文献
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Polystyrene/organoclay nanocomposites were prepared by melt intercalation in the presence of elastomeric impact modifiers. Three different types of organically modified montmorillonites; Cloisite® 30B, 15A, and 25A, were used as reinforcement, whereas poly [styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS‐g‐MA) and poly(ethylene‐b‐butyl acrylate‐b‐glycidyl methacrylate) (E‐BA‐GMA) elastomeric materials were introduced to act as impact modifier. Owing to its single aliphatic tail on its modifier and absence of hydroxyl groups, Cloisite® 25A displayed the best dispersion in the polystyrene matrix, and mostly delaminated silicate layers were obtained in the presence of SEBS‐g‐MA. This was attributed to the higher viscosity of SEBS‐g‐MA compared with both E‐BA‐GMA and poly(styrene‐co‐vinyloxazolin) (PS). In addition, the compatibility between SEBS‐g‐MA and PS was found to be better in comparison to the compatibility between E‐BA‐GMA and PS owing to the soluble part of SEBS‐g‐MA in PS. The clay particles were observed to be located mostly in the dispersed phase leading to larger elastomeric domains compared with binary PS/elastomer blends. The enlargement of the elastomeric domains resulted in higher impact strength values in the presence of organoclay. Good dispersion of Cloisite® 25A in PS/SEBS‐g‐MA blends enhanced the tensile properties of this nanocomposite produced. It was observed that the change in the strength and stiffness of the ternary nanocomposites mostly depend on the type of the elastomeric material. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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In the present study, glycidyl methacrylate (GMA) grafted medium density polyethylene (MDPE‐g‐GMA) was synthesized in the molten state and applied as a reactive compatibilizer in MDPE/polyamid6 (PA6) and in MDPE/poly(ethylene terephtalate) (PET) blends. Graft copolymerization of GMA onto MDPE was performed in presence and absence of styrene, with different concentrations of dicumyl peroxide (DCP) as a radical initiator. In the presence of styrene, the MDPE‐g‐GMA with 6% GMA was obtained by addition of only 0.1 phr of DCP. Furthermore, the maximum grafting was reached when 0.6 and 0.7 phr concentration of DCP for styrene containing and styrene free samples were used, respectively. Torque‐time measurement showed faster grafting reaction rate in the presence of styrene. Four MDPE‐g‐GMA samples were selected as compatibilizers in the blends. Furthermore, the effects of melt flow index and grafting content of compatibilizers on mechanical properties and morphology of the blends were investigated through tensile tests and SEM analysis. Tensile test results indicated that the presence of compatibilizers in the blends led to 250 and 133% increase in elongation at break for PA6 and PET blends, respectively. Moreover, the best tensile results for blends were obtained using MDPE‐g‐GMA with high flow ability. The average particle size of the dispersed phase decreased by 350% for PA6 and 300% for PET blends compared with nonreactive blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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This work aims at studying the toughening process of poly(butylene terephthalate) (PBT) through its blends with styrene‐butadiene‐styrene block copolymers (SBS), in the presence of poly(styrene‐ran‐glicydil methacrylate) (PS‐GMA) as reactive compatibilizer. High values of impact strength were attained for PBT/SBS blends without the compatibilizer; however, this improvement is achieved for blends with SBS having similar viscosity compared to PBT, at high SBS content (40 wt %) and for blends prepared under specific processing conditions. The efficiency of the in situ compatibilization of PBT/SBS blends by PS‐GMA was found to be strongly dependent on the SBS and PS‐GMA molecular characteristics. Better compatibilizing results were observed through fine phase morphologies and lower ductile to brittle transition temperatures (DBTT) as the interfacial interaction and stability of the in situ formed compatibilizer are maximized, that is, when the miscibility between SBS and PS‐GMA and reaction degree between PBT and PS‐GMA are maximized. For the PBT/SBS/PS‐GMA blends under study, this was found when it is used the SBS with higher polystyrene content (38 wt %) and with longer PS blocks (Mw = 20,000 g mol?1) and also the PS‐GMA with moderate GMA contents (4 wt %) and with molecular weight similar to the critical one for PS entanglements (Mc = 35,000 g mol?1). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5795–5807, 2006 相似文献
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In this article, a particular phase morphology of immiscible polyamide 12/polystyrene (PA12/PS) blends prepared via in situ anionic ring-opening polymerization of Laurolactam (LL) in the presence of PS was investigated. SEM and FTIR were used to analyze the morphology of the blends. The results showed that PS is dispersed as small droplets in the continuous matrix of PA12 when PS content is less than 5 wt %. When the PS content is higher than 10 wt %, two particular phase morphologies appeared. First, dispersed PS-rich particles with the spherical inclusions of PA12 can be found when PS content is between 10 wt % and 15 wt %. Then, the phase inversion (the phase morphology of the PA12/PS blends changes from the PS dispersed/PA12 matrix to PA12 dispersed/PS matrix system) occurred when PS content is higher than 20 wt %, which is completely different from traditional polymer blends prepared by melt blending. The possible reason for the particular morphology development was illuminated through phase inversion mechanism. Furthermore, the stability of the phase morphologies of the PA12/PS blends was also investigated. SEM showed that the particular morphology is instability, and it will be changed upon annealing at 230°C for 30 min. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
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在哈克流变仪中将炭黑(CB)与聚苯乙烯(PS)、尼龙6(PA6)共混,研究了CB在PS/PA6/CB共混体系中的分散情况及CB含量和PS与PA6的质量比对PS/PA6/CB共混体系导电性能、微观形态的影响。结果表明,CB在PS/PA6/CB共混体系中只分散在PA6中;PS/PA6/CB共混体系的导电性能随着CB含量的增加而增强,CB的体积分数在20%~40%时,PS/PA6/CB共混体系的电导率增幅明显;PS、PA6两相的微观尺寸随CB含量增加而变小;PS/PA6/CB共混体系中PS与PA6质量比约为80/20时,PS/PA6/CB共混体系的导电性能最好。 相似文献
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In situ polymerization and in situ compatibilization was adopted for preparation of ternary PA6/PS‐g‐PA6/PS blends by means of successive polymerization of styrene, with TMI and ε‐caprolactam, via free radical copolymerization and anionic ring‐opening polymerization, respectively. Copolymer poly(St‐g‐TMI), the chain of which bears isocyanate (? NCO), acts as a macroactivator to initiate PA6 chain growth from the PS chain and graft copolymer of PS‐g‐PA6 and pure PA6 form, simultaneously. The effect of the macroactivator poly(St‐g‐TMI) on the phase morphology was investigated in detail, using scanning electron microscopy. In case of blends with higher content of PS‐g‐PA6 copolymer, copolymer nanoparticles coexisting with the PS formed the matrix, in which PA6 microspheres were dispersed evenly as minor phase. The content of the compositions (homopolystyrene, homopolyamide 6, and PS‐g‐PA6) of the blends were determined by selective solvent extraction technique. The mechanical properties of PA6/PS‐g‐PA6/PS blends were better than that of PA6/PS blends. Especially for the blends T10 with lower PS‐g‐PA6 copolymer content, both the flexural strength and flexural modulus showed significantly improving because of the improved interfacial adhesion between PS and PA6. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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Influence of morphology and ammonium polyphosphate dispersion on the flame retardancy of polystyrene/nylon‐6 blends
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Chang Lu Qing‐qing Cao Xiao‐ning Hu Cui‐yun Liu Xin‐hui Huang Yu‐qing Zhang 《火与材料》2014,38(8):765-776
The influences of the distribution of ammonium polyphosphate (APP) in polystyrene/nylon‐6 [PS/polyamide‐6 (PA6)] blends and the continuity of the (PA6 + APP) phase on flame retardancy were investigated. The flame retardant properties were evaluated by limiting oxygen index (LOI), vertical flammability test and cone calorimeter tests. The results showed that APP is exclusively dispersed in the PA6 phase, and (PA6 + APP) phase formed a continuous state when the content of PA6 in PS/PA6 blends was higher than 32% (w/w). For blends with a continuous (PA6 + APP) phase, the decrease of PA6 content caused an increase in LOI values from 26% to 33% and a reduction of peak heat release rate. The improvement of flame retardancy was attributed to the increase of APP concentration in the PA6 phase, which benefited the fast formation of a continuous intumescent charred layer. The transformation of (PA6 + APP) phase morphology from a continuous state to a discontinuous state at a PA6 content of below 32% (w/w) caused a decrease in LOI. Results of thermo‐gravimetric and cone calorimeter tests indicated that the discontinuous intumescent charred layer thus formed could be responsible for the deterioration of flame retardant properties, which was also confirmed by scanning electron microscopy. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Phase morphology development in ternary uncompatibilized and reactively compatibilized blends based on polyamide 6 (PA6), polypropylene (PP) and polystyrene (PS) has been investigated. Reactive compatibilization of the blends has been performed using two reactive precursors; maleic anhydride grafted polypropylene (PP-g-MA) and styrene maleic anhydride copolymer (SMA) for PA6/PP and PA6/PS pairs, respectively. For comparison purposes, uncompatibilized and reactively compatibilized PA6/PP and PA6/PS binary blends, were first investigated. All the blends were melt-blended using a co-rotating twin-screw extruder. The phase morphology investigated using scanning electron microscope (SEM) and selective solvent extraction tests revealed that PA6/PP/PS blends having a weight percent composition of 70/15/15 is constituted from polyamide 6 matrix in which are dispersed composite droplets of PP core encapsulated by PS phase. Whereas, a co-continuous three-phase morphology was formed in the blends having a composition of 40/30/30. This morphology has been significantly affected by the reactive compatibilization. In the compatibilized PA6/(PP/PP–MA)/(PS/SMA) blends, PA6 phase was no more continuous but gets finely dispersed in the PS continuous phase. The DSC measurements confirmed the dispersed character of the PA6 phase. Indeed, in the compatibilized PA6/(PP/PP–MA)/(PS/SMA) blends where the PA6 particle size was smaller than 1 μm, the bulk crystallization temperature of PA6 (188 °C) was completely suppressed and a new crystallization peak emerges at a lower temperature of 93 °C as a result of homogeneous nucleation of PA6. 相似文献
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Seon‐Joon Kim Dong‐Keun Kim Won‐Jei Cho Chang‐Sik Ha 《Polymer Engineering and Science》2003,43(6):1298-1311
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. 相似文献