NX8000K对PP/LDPE共混体系增透增韧改性

通过熔融共混法制备聚丙烯(PP)/低密度聚乙烯(LDPE)共混物,利用成核剂NX8000K对PP/LDPE共混物进行改性.借助差示扫描量热仪(DSC)、X射线衍射仪(XRD)、偏光显微镜(POM)等研究了NX8000K对PP/LDPE共混物透明性、热性能、结晶行为和力学性能的影响.结果表明:随着LDPE含量增加,PP/...     

高结晶度iPP/TMC-300复合材料的制备及性能

以全同立构聚丙烯(iPP)和癸二酰二苯甲酰肼(TMC-300)为原料,通过熔融共混技术制备了iPP/TMC-300复合材料,采用DSC、XRD、SEM、POM和力学测试仪器考察了成核剂TMC-300对iPP结晶和熔融行为、晶体结构以及力学性能等的影响。结果表明:TMC-300对iPP有显著的成核效果,当TMC-300的质量分数为0.6%时,iPP的结晶温度由纯iPP的117.2℃提高到126.9℃,其成核效率可达到56.3%;在130℃下等温结晶,纯iPP的半结晶时间(t1/2)为4.85 min,当TMC-300的质量分数为0.2%时,t1/2变为0.52 min,减小了89%。同时,TMC-300的添加并没有改变iPP的晶体结构,而且添加TMC-300的iPP的冲击断裂表面相对纯iPP呈现出了明显的多褶皱韧性断裂形貌特征,TMC-300的质量分数为0.2%时,复合材料的断裂伸长率由纯iPP的674.8%提高到了833.2%,缺口冲击强度由32.5 J/m提高到了43.2 J/m。将TMC-300与成核剂TMC-328、HPN-68L对iPP的结晶与力学性能影响进行了对比,TMC-300的质量分数为0.2%时的结晶峰温度为126.2℃,较TMC-328的质量分数为0.2%时的125.2℃略高,其缺口冲击强度(43.2 J/m)较HPN-68L的质量分数为0.2%时的(37.3 J/m)提高了15.8%。     

PP/PE⁃LD/NX8000K高韧高透明材料的制备及性能研究

以聚丙烯(PP)为基体,低密度聚乙烯(PE-LD)和NX8000K成核剂为添加剂,通过熔融共混法制备了PP/PE-LD/NX8000K高韧高透明共混材料.采用差示扫描量热、X射线衍射、偏光显微镜、雾度测试仪和冲击试验机等仪器对共混材料的结晶行为、晶体形貌、透明性和力学性能进行了表征与测试.结果表明,PE-LD能阻碍PP...     

β成核剂改性iPP的熔融结晶行为与力学性能研究

采用3种β成核剂(NT-A,NT-B和NT-C)制备了β晶等规聚丙烯(β-iPP)样品,应用差示扫描量热仪(DSC)分析、偏光显微镜(POM)观察和力学性能测试研究了β-iPP的熔融、结晶行为和力学性能。结果表明:加入β成核剂后,诱导iPP由α晶向β晶转变,结晶温度提高,球晶明显细化。3种β成核剂的成核效率和改性样品的缺口冲击强度顺序为NT-C>NT-B>NT-A,添加NT-C质量分数0.050%时,样品的最大缺口冲击强度可达纯iPP的3.7倍。     

成核剂对增韧聚丙烯力学性能的影响

主要研究成核剂种类及用量对乙烯－辛烯共聚物（POE）增韧聚丙烯（PP）力学性能的影响。研究表明：随着成核剂NA1的加入,PP／POE共混物的透明性、冲击强度、弯曲强度、拉伸屈服强度均明显提高,研制的改性PP的透明性、韧性和刚性得到了平衡。     

HPN-68L成核剂对顺丁橡胶增韧PP材料结晶行为和力学性能的影响

采用物理共混的方法,研究了成核剂HPN-68L对顺丁橡胶(BR)增韧等规聚丙烯(iPP)材料性能的影响。利用广角X射线衍射仪(WXRD)、差示扫描量热仪(DSC)、偏光显微镜(POM)等测试手段探究了HPN-68L对iPP/BR共混物的结晶行为和力学性能的影响。结果表明,HPN-68L在高温下诱导iPP结晶,并且起到了物理凝胶的作用,HPN-68L的添加使BR在降温过程中由于iPP的凝固化而被限阈均匀地分散在基体中,BR在iPP基体中得到固定从而减小团聚带来的材料性能恶化。当HPN-68L质量分数为0.6%(以iPP、BR、HPN-68L总质量为基准,下同),加入30%顺丁橡胶时,材料的最大冲击强度达到17.216 kJ/m²,比纯iPP冲击强度高出236.91%,断裂伸长率由69.23%提高至176.32%。     

有机磷酸盐成核剂粒径对PP性能的影响

通过调控反溶剂法中的转速、反溶剂与溶剂配比、溶液浓度等条件制备了不同粒径的2,2’–亚甲基双(4,6–二叔丁基苯基)磷酸钠(NA–40)成核剂,考察了NA–40粒径对等规聚丙烯(i PP)力学性能的影响,并利用差示扫描量热(DSC)仪研究了NA–40粒径对i PP结晶性能的影响。结果表明,随着NA–40粒径的增加,NA–40对i PP力学性能的改善作用变弱。NA–40平均粒径为(17.7±2.2)μm时,i PP/NA–40–1的弯曲弹性模量、弯曲强度和拉伸强度与纯i PP相比,分别提高了44.5%,20.5%和8.3%,相应的缺口冲击强度有所降低;当NA–40平均粒径为(52.6±1.1)μm时,i PP/NA–40–4的弯曲弹性模量、弯曲强度和拉伸强度的增幅分别降至16.8%,2.3%和6.4%。在较低的降温速率下,NA–40粒径对结晶峰值温度(Tc)的影响不明显,提高降温速率对Tc的影响开始显现。用扫描电子显微镜观察NA–40形貌发现,NA–40呈棒状,加工过程影响NA–40粒径,但对NA–40形貌没有影响。利用偏光显微镜观察NA–40在i PP熔体中的分散性,粒径较小的NA–40能够均匀分散在i PP熔体中,而粒径较大的分散性差,大大降低了NA–40的有效成核浓度,影响了NA–40对i PP力学性能及结晶性能的改善作用。     

有机磷酸酯及其衍生物对聚丙烯性能的影响

采用阳离子取代基团为H、Na、Al的有机磷酸酯和有机磷酸盐作为成核剂加入聚丙烯(PP)中,研究了它们对PP结晶行为、力学性能和透明性能的影响。结果表明:当成核剂添加量均为0.2%时,有机磷酸酯、钠盐和铝盐使PP的结晶温度分别提高了0.94、13.8和3.52℃,弯曲模量则分别提高了5.36%、38.3%和8.98%,其中钠盐成核PP样品的雾度值最低。由此可知,钠盐的成核效果最好,而有机磷酸酯和铝盐对PP的成核作用不明显。     

成核剂对聚丙烯力学性能与结晶行为的影响

研究了两种类型的成核剂对国产共聚聚丙烯的结晶形态以及拉伸强度、冲击强度的影响。结果表明:加入TMB-5型成核剂,聚丙烯的冲击强度有一定程度改善,w(TMB-5)为0.1%时,改性聚丙烯的缺口冲击强度达到最大;TMX-2型成核剂可改善聚丙烯的拉伸性能,但抗冲击性能降低较大;TMB-5型成核剂可显著地改变聚丙烯的结晶行为,诱导聚丙烯在结晶过程中主要形成β晶;TMX-2型成核剂可诱导聚丙烯在结晶过程中主要生成α晶,与纯PP相比,α晶的形成能力增强。     

Structure and mechanical properties of isotactic polypropylene and iPP/talc blends functionalized by electron beam irradiation

The structure and mechanical properties of isotactic polypropylene (iPP) functionalized by electron beam irradiation are investigated by differential scanning calorimetry, wide‐angle X‐ray diffraction, thermogravimetry, thermomechanical analysis, melt index and mechanical measurements. The experimental results show that the degree of crystallinity, the thermal degradation temperature and the dimensional stability increase with dose in the range 0–5 kGy. At 5 kGy, the initial and final degradation temperatures of the irradiated iPP are raised by 66 °C and 124 °C, respectively. The melt index increases with increasing dose. The mechanical measurements show that the stiffness of iPP is greatly enhanced by electron beam irradiation. A small dose of irradiation (0.75 kGy) can increase the Young's modulus to 1284 MPa compared with 1112 MPa for unirradiated iPP. Adding 10 % by weight of irradiated iPP powder into iPP/talc (70/20 % by weight) blends, changes the processing parameters significantly and makes the Young's modulus rise substantially. At a dose of 40 kGy the Young's modulus of iPP/talc blend jumps to 3611 MPa against the original 2201 MPa. © 2000 Society of Chemical Industry     

Combined effect of organic phosphate sodium and nanoclay on the mechanical properties and crystallization behavior of isotactic polypropylene

Combined effect of α‐nucleating agent (NA) sodium 2,2′‐methylene‐bis(4,6‐di‐tert‐butylphenyl) phosphate (NA11) and nanoclay (NC) on the mechanical properties and crystallization behavior of isotactic polypropylene (iPP) was investigated by mechanical testing, wide‐angle X‐ray scattering (WAXD), differential scanning calorimetry (DSC), polarized optical microscopy (POM), and scanning electron microscopy (SEM). The mechanical testing results indicated that the separate addition of NA11 and NC only increased the stiffness of iPP while the combined addition of NA11, NC, and maleic anhydride grafted polypropylene (PP‐g‐MA) simultaneously improved stiffness and toughness of iPP. Compared to pure iPP, the tensile strength, the flexural modulus, and impact strength of iPP composites increased 9.7, 38.6, and 42.9%, respectively. The result indicated good synergistic effects of NC, NA11, and PP‐g‐MA in improving iPP mechanical properties. WAXD patterns revealed NA11, and NC only induced the α‐crystals of iPP. SEM micrograph showed that the PP‐g‐MA could effectively improve the dispersing of NC in iPP. Finally, the nonisothermal crystallization kinetics of neat iPP and PP nanocomposites was described by Caze method. The result indicated that the addition of NA overcame the shortcoming of low crystallization rate of NC nanocomposites and maintained the excellent mechanical properties, which is another highlight of the combined addition of NAs and nanoclay. Meanwhile, the result showed that nuclei formation and spherulite growth of iPP were affected by the presence of NA and nanoclay. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

耐刮擦、高流动PP/SEBS热塑性弹性体的研制

采用熔融共混法制备了聚丙烯(PP)/氢化苯乙烯–丁二烯–苯乙烯嵌段共聚物(SEBS)热塑性弹性体,研究了乙烯丙烯酸酯共聚物润滑偶联改性剂(YY–503和YY–5031)、芥酸酰胺和高分子量硅酮(E525)4种改性剂对PP/SEBS弹性体的加工性能、力学性能和耐刮擦性能的影响。结果表明,4种改性剂的加入能显著提高弹性体的熔体流动速率(MFR),添加YY–503和E525的弹性体MFR提升更为显著,分别为12.6 g/10 min和13.5 g/10 min,比未添加时提高了2 471.4%和2 655.1%;添加芥酸酰胺的弹性体拉伸强度和断裂伸长率最低,比未添加改性剂时分别下降了58.5%和63.2%,添加YY–503和YY–5031的弹性体拉伸强度分别为10.6 MPa和9.8 MPa,比未添加改性剂时分别提高23.2%和19.5%;未添加改性剂弹性体的色差值(ΔL)为18.5,而添加YY–503和YY–5031的弹性体ΔL仅为1.3和1.5;扫描电子显微镜测试发现,添加YY–503和YY–5031的弹性体中没有出现明显孔洞,碳酸钙良好分散,与基体结合力良好。添加质量分数为2%的YY–503可获得力学性能、加工性能和耐刮擦性能优异的PP/SEBS弹性体。     

不同成核剂成核聚丙烯的结晶行为与力学性能

制备了６种成核剂成核聚丙烯（ＰＰ）母料研究了成核母料和成核母料／ＰＰ的结晶,熔融行为,力学性能和透明性等物理性能,不同成核在成核母材料和成核母料／ＰＰ中对ＰＰ的结晶与熔融行为以及性能有不同的作用,观察到成核型Ａ成核ＰＰ具有较高的结晶温度与综合性能,而成核剂Ｂ成核ＰＰ的透明性较好。     

成核剂对聚丙烯结晶形态及力学性能的影响

研究了有机磷酸盐成核剂对聚丙烯(PP)结晶行为及力学性能的影响．采用差示扫描量热法和偏光显微镜分析比较了3种成核剂。结果表明：添加质量分数为0.2％的成核剂,可使PP的结晶峰温度提高15．6～17．8℃。结晶度增加2．5％～10．5％,同时提高了结晶速率,球晶尺寸大幅度降低;试样的拉伸强度、弯曲模量均有提高。弯曲模量提高15．5％～44．9％。     

Mechanical and rheological properties of PP/SEBS/OMMT ternary composites

The microstructure and mechanical properties of polypropylene (PP)/OMMT binary nanocomposites and PP/styrene‐6‐(ethylene‐co‐butylenes)‐6‐styrene triblock copolymer (SEBS)/OMMT ternary nanocomposites were investigated using X‐ray diffraction (XRD), transmission electron microscopy (TEM), and rheology and electromechanical testing machine. The results show that the organoclay layers are mainly intercalated and partially exfoliated in the PP‐based nanocomposites. The additions of SEBS and OMMT have no significant effect on the crystallization behavior of PP. At the same time, it can be concluded that the polymer chains of PP and SEBS have intercalated into the organoclay layers and increase the gallery distance after blending process based on the analytical results from TEM, XRD, and rheology, which result in the form of a percolated nanostructure in the PP‐based nanocomposites. The results of mechanical properties show that SEBS filler greatly improve the notched impact strength of PP, but with the sacrifice of strength and stiffness. OMMT can improve the strength and stiffness of PP and slightly enhance the notched impact strength of PP/PP‐g‐MA. In comparison with neat PP, PP/OMMT, and PP/SEBS binary composites, notched impact toughness of the PP/SEBS/OMMT ternary composites significantly increase. Moreover, the stiffness and strength of PP/SEBS/OMMT ternary nanocomposites are slightly enhanced when compared with neat PP. It is believed that the synergistic effect of both SEBS elastomer and OMMT nanoparticles account for the balanced mechanical performance of the ternary nanocomposites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

SEBS/蒙脱土纳米复合材料结构和性能研究

采用溶液混合方法制备了氢化苯乙烯/丁二烯三元嵌段共聚物(SEBS)/有机蒙脱土(OM-MT)纳米复合材料(NC)。对SEBS/OMMT NC的插层结构和物理力学、动态力学、耐热等性能进行了研究。结果表明,与SEBS复合,OMMT层间距明显增大,制备出具有插层型结构的NC。加入OMMT可明显提高SEBS的拉伸断裂强度、300%定伸强度和断裂伸长率,但永久变形也增大。DMA研究表明,SEBS/OMMT NC的储能模量和损耗模量比纯SEBS显著提高,PEB链段的tanδ降低,而PS链段增加。SEBS/OMMT NC比SEBS的热稳定性明显提高。     

Crystallization behavior and optical and mechanical properties of isotactic polypropylene nucleated with rosin‐based nucleating agents

Background: Rosin‐based nucleating agents, as natural products, do not have any toxicity; hence they could be used in the industrial processing of polypropylene for the manufacture of food containers. As a result they have been the subject of considerable scientific interest in the literature. In this paper, the non‐isothermal crystallization behavior, and optical and mechanical properties of isotactic polypropylene (iPP) nucleated with rosin‐based nucleating agents are reported. Polarized optical microscopy, scanning electron microscopy and wide‐angle X‐ray diffraction were used to investigate the morphology and crystal structure of iPP with different rosin‐based nucleators. The effects of a 1:1:1 co‐crystal on the properties of iPP were also investigated. Results: The addition of rosin‐based nucleating agents led to the following changes in properties: (a) shortened crystallization half time, (b) decreased size of iPP crystals, (c) slightly increased crystallinity and (d) increased transparency, gloss, flexural modulus and tensile strength. The shrinkage of nucleated iPPs was similar to that of the blank iPP. Conclusion: Rosin‐based nucleating agents in iPP were shown to be effective for nucleating crystals, reducing their size and causing preferential growth along the b‐axis, but suppressing detectable spherulites. The 1:1:1 co‐crystal was effective at 0.2 wt%, a greater concentration giving little additional improvement. Copyright © 2007 Society of Chemical Industry