黏土结构对聚氯乙烯/黏土复合材料性能的影响

用两种不同结构的黏土伊利石和海泡石作为填料填充到聚氯乙烯(PVC)树脂中,研究黏土结构对PVC性能的影响。结果表明:黏土的结构不同,对PVC的性能影响也存在明显差异。伊利石对提高PVC的拉伸强度优于海泡石;而海泡石对提高PVC的冲击强度优于伊利石。伊利石提高了PVC的弯曲强度,对弯曲模量的影响不大;而海泡石降低了PVC的弯曲强度,但明显加大了PVC的弯曲模量。海泡石对提高PVC的热变形温度优于伊利石。     

插层剂对PA66/蒙脱土纳米复合材料性能影响

将不同插层剂改性的蒙脱土与尼龙66(PA66)通过熔融共混制得了纳米复合材料,对复合材料的热变形温度和力学性能进行了研究。结果表明,与纯PA66相比,3种插层剂改性的蒙脱土／PA66纳米复合材料的热变形温度、弯曲模量、弯曲强度均有明显提高,拉伸模量和屈服强度也有所提高,但断裂伸长率和缺口冲击强度则明显下降;含极性羟基的插层剂对复合材料的综合改性效果较好,含2个长链非极性烃基的插层剂改性效果较差;加入环氧树脂后,复合材料的热变形温度、拉伸模量和弯曲模量有所降低,屈服强度、弯曲强度、断裂伸长率和缺口冲击强度则有所增加。     

高性能聚氯乙烯复合材料的研究

以聚氯乙烯(PVC)为基体、热塑性聚氨酯弹性体(PUR–T)为增韧剂、连续玻璃纤维(GF)为增强剂,通过熔体浸渍挤出工艺制备高性能PVC复合材料,并对其力学性能、耐热性能和动态力学性能进行研究。结果表明,随着PUR–T或连续GF含量增加,复合材料的力学性能和耐热性能均得到提高,当PUR–T/PVC质量比为2/8,连续GF质量分数为30%时,复合材料的拉伸强度、缺口冲击强度、弯曲强度、弯曲弹性模量、维卡软化温度分别为83.42 MPa,19.81 k J/m2,106.33 MPa,8 823.36 MPa和74.1℃;随着连续GF含量增加,复合材料的储能模量和玻璃化转变温度提高,损耗因子降低;扫描电子显微镜测试结果表明连续GF在PVC中保持了较长的长度,分散性良好。     

PVC/脲醛改性酶解木质素复合材料的性能

采用PVC树脂和酶解木质素制备得到PVC/酶解木质素复合材料,研究酶解木质素及脲醛改性酶解木质素对复合材料性能的影响.结果表明:随着酶解木质素用量的增大,PVC/酶解木质素复合材料的拉伸强度和冲击强度下降,而经过改性处理后得到的脲醛改性酶解木质素,与PVC之间的相容性得到改善,大大提高了复合材料的力学性能.另外,酶解木质素和脲醛改性酶解木质素加入后均提高了PVC/酶解木质素复合材料的维卡软化点.     

聚氯乙烯/粉煤灰复合材料的制备与性能研究

制备了聚氯乙烯/粉煤灰复合材料,研究了粉煤灰的不同表面处理方式对共混物的力学性能和耐温性能的影响。结果表明:湿法处理粉煤灰的效果最好,不做处理的效果最差;粉煤灰会降低PVC材料的缺口冲击强度;添加5份处理过的粉煤灰可以提高PVC材料的拉伸强度;添加粉煤灰可以提高PVC材料的弯曲强度和弯曲模量,同时,耐温性也有一定的提高。     

水滑石填充PVC复合材料的制备及性能研究

采用液态丁腈橡胶(LNBR)对水滑石(HT)进行表面包覆改性制备了LNBR/HT,并用其填充聚氯乙烯(PVC)制备了复合材料,采用红外光谱仪(FTIR)简支梁冲击试验机、万能试验机、氧指数测定仪、动态力学分析仪(DMA)、、扫描电子显微镜(SEM)等仪器研究了LNBR对HT的改性方式和改性前后HT含量对复合材料力学性能...     

Improving mechanical properties of poly(vinyl chloride) by doping with organically functionalized reactive nanosilica

Nanosilica particles are functionalized by in situ surface‐modification with trimethyl silane and vinyl silane. Resultant reactive nanosilica (coded as RNS) contains double bonds and possesses good compatibility with vinyl chloride (VC) and polyvinyl chloride (PVC). This makes it feasible for RNS to copolymerize with VC generating RNS/PVC composites via in situ suspension polymerization. As‐prepared RNS/PVC composite resins are analyzed by means of FTIR. The tensile strength and impact strength of compression‐molded RNS/PVC composites are measured and compared with that of compression‐molded PVC composites doped with dispersible nano‐SiO₂ particles (abridged as DNS) surface‐modified with trimethyl silane alone. Moreover, the thermal stability of compression‐molded RNS/PVC and DNS/PVC composites is evaluated by thermogravimetric analysis. It has been found that RNS/PVC composites possess greatly increased impact strength and tensile strength than PVC matrix, while DNS/PVC composites possess higher impact strength than PVC matrix but almost the same tensile strength as the PVC matrix. This implies that DNS is less effective than RNS in improving the mechanical strength of PVC matrix. Particularly, RNS/PVC composites prepared by in situ suspension polymerization have much higher mechanical strength than RNS/PVC composites prepared by melt‐blending, even when their nanosilica content is only 1/10 of that of the melt‐blended ones. Besides, in situ polymerized RNS/PVC and DNS/PVC composites have better thermal stability than melt‐blended nanosilica/PVC composites. Hopefully, this strategy, may be extended to fabricating various novel high‐performance polymer‐matrix composites doped with organically functionalized nanoparticles like RNS. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Influence of interfacial interactions on the properties of PVC/cellulosic fiber composites

The surface properties at the interface between thermoplastic and cellulosic fibers strongly influence the mechanical properties of plastic/cellulosic fiber composites. This paper examines the role of surface acid-base properties of plasticized PVC and cellulosic fibers on the mechanical properties of the composites. The acid-base surface characteristics of cellulosic fibers were modified by treating the fibers with γ-aminopropyltriethoxysilane (A-1100), dichlorodiethylsilane, phthalic anhydride, and maleated polypropylene. The empirical acid (K_A) and base (K_D) characteristics (i.e., electron donor/acceptor abilities) of untreated and treated fibers, as well as plasticized PVC, were determined using inverse gas chromatography (IGC) technique. These parameters were used to yield information on the acid-base pair interactions that were correlated with the tensile and notched Izod impact properties of the composites. Acid-base pair interactions have been found to be a valuable parameter in the design of surface modification strategies intended to optimize the tensile strength of the composites. By tailoring the acid-base characteristics of cellulosic fibers and plasticized PVC, a composite with equal tensile strength and greater modulus than unfilled PVC was developed. However, the acid-base factors did not correlate with tensile modulus, the elongation at break, and the notched Izod impact property of PVC/newsprint fiber composites. Aminosilane has been observed to be a suitable adhesion promoter for PVC/wood composites improving significantly the tensile strength of the composites. Other treatments (dichlorodiethylsilane, phtalic anhydride, and maleated polypropylene) were found to be ineffective, giving similar strength compared to the composites with untreated cellulosic fibers. FTIR spectroscopy results suggested that aminosilane was effective because treated cellulosic fibers can react with PVC to form chemical bonds. The resulting bond between PVC and cellulosic fibers accounts for the effectiveness of aminosilane, when compared with other coupling agents.     

PVC/MBS/埃洛石纳米管复合材料的制备及其性能

采用熔融共混法制备了聚氯乙烯(PVC)/甲基丙烯酸甲酯-丁二烯-苯乙烯共聚物(MBS)/埃洛石纳米管(HNTs)三元复合材料,研究了HNTs对PVC/MBS共混体系力学性能、热性能和微观结构的影响。结果表明:HNTs与MBS可协同增韧PVC,使复合材料的强度和刚性得到改善,当HNTs的填充量为3 phr时,PVC/MBS(100/3)共混体系的冲击强度、拉伸强度、弯曲强度和弯曲模量分别提高了57.7%、12.1%、7.6%和45.9%;其冲击断面呈现韧性断裂特征;TEM观察结果发现,HNTs在PVC/MBS共混体系中具有良好的分散状态;热失重分析显示,HNTs对PVC/MBS共混体系热稳定性的提高能起到一定作用。     

粉煤灰微珠改性PVC复合材料研究

研究了PVC/粉煤灰微珠复合材料、PVC/CaCO3复合材料的力学性能。实验结果表明:当粉煤灰微珠添加量为5份时,PVC/粉煤灰微珠复合材料的室温缺口冲击强度为46 kJ/m2,拉伸强度为47 MPa达到最大值;弯曲模量随着粉煤灰微珠增加呈线性增加;PVC/粉煤灰微珠复合材料的综合力学性能要好于PVC/CaCO3复合材料。SEM测试表明:经表面改性后的粉煤灰微珠在PVC基体中具有很好的分散性和相容性。     

不同改性蒙脱土对ENR/PVC共混型TPV填充效果的研究

采用熔融插层法制备了聚氯乙烯/蒙脱土(PVC/MMT)插层产物,再将该产物与环氧化天然橡胶(ENR)在密炼机中进行熔融共混制备ENR/PVC/MMT共混型热塑性弹性体(TPV),研究了不同改性MMT对共混物力学性能、热稳定性以及动态力学性能的影响。结果表明:二甲基双十八烷基铵改性蒙脱土(MMT-2C18)能显著提高ENR/PVC共混型TPV的拉伸强度,无机MMT能显著提高ENR/PVC的断裂伸长率,十八烷基铵改性蒙脱土(MMT-C18)会降低TPV的拉伸强度和断裂伸长率;有机改性MMT会促进TPV中PVC的降解,使得复合材料的热稳定性降低;动态热力学分析显示,MMT可使复合材料的储能模量增加,其中有机改性MMT使材料的损耗因数(tanδ)曲线峰强降低,峰宽变宽。     

聚氯乙烯/赤泥复合材料的制备与性能研究

制备了聚氯乙烯(PVC)/赤泥复合材料,研究了赤泥的不同表面处理方式对共混物的力学性能和耐温性能的影响。结果表明:湿法处理赤泥的效果最好,不做处理的效果最差;赤泥的含量在15份时,共混物的缺口冲击强度和拉伸强度最大;添加赤泥可以提高PVC材料的弯曲强度和弯曲模量,同时,耐温性能也有一定程度的提高。     

表面处理对木粉增强PVC发泡复合板材性能的影响

研究表面处理的木粉对发泡聚氯乙烯(PVC)板材的增强改性效果。使用铝酸酯偶联剂、丙烯酸丁酯预聚物对木粉进行表面处理，将其混合到聚氯乙烯发泡板材配料中进行板材加工生产，结果表明，经处理的木粉能提高发泡PVC板材的拉伸强度和冲击强度。用铝酸酯偶联剂处理木粉的发泡板材力学性能好于用丙烯酸丁酯预聚物处理的板材；而用丙烯酸丁酯预聚物处理木粉的复合材料在流变加工性能优于用铝酸酯处理木粉的复合材料。     

尼龙6/硼酸镁晶须复合材料的制备与研究

使用自制的硼酸酯偶联剂BE-1和BE-2在硼酸镁晶须表面引发聚合形成有机涂层,用改性后的硼酸镁晶须制备尼龙6/硼酸镁晶须复合材料并对其性能进行了研究。结果表明:随着硼酸镁晶须含量的增加,复合材料的拉伸强度、弯曲强度及热变形温度出现了先增加后降低的趋势,当硼酸镁晶须在复合材料基体中的含量为30%时,复合材料的力学性能最佳,BE-1改性的尼龙6/硼酸镁晶须复合材料拉伸强度、弯曲强度、冲击强度、热变形温度分别比未改性的尼龙6/硼酸镁晶须复合材料提高了14.47%、13.72%、29.73%和7.19%;BE-2改性的尼龙6/硼酸镁晶须复合材料的拉伸强度、弯曲强度、冲击强度、热变形温度分别比未改性的尼龙6/硼酸镁晶须复合材料提高了23.37%、22.54%、37.84%和10.78%。     

Comparative Studies of Mechanical and Interfacial Properties Between Jute Fiber/PVC and E-Glass Fiber/PVC Composites

Composites (50 wt% fiber) of jute fiber reinforced polyvinyl chloride (PVC) matrix and E-glass fiber reinforced PVC matrix were prepared by compression molding. Mechanical properties such as tensile strength (TS), tensile modulus (TM), bending strength (BS), bending modulus (BM) and impact strength (IS) of both types of composites was evaluated and compared. Values of TS, TM, BS, BM and IS of jute fiber/PVC composites were found to be 45 MPa, 802 MPa, 46 MPa, 850 MPa and 24 kJ/m², respectively. It was observed that TS, TM, BS, BM and IS of E-glass fiber/PVC composites were found to increase by 44, 80, 47, 92 and 37.5%, respectively. Thermal properties of the composites were also carried out, which revealed that thermal stability of E-glass fiber/PVC system was higher. The interfacial adhesion between the fibers (jute and E-glass) and matrix was studied by means of critical fiber length and interfacial shear strength that were measured by single fiber fragmentation test. Fracture sides after flexural testing of both types of the composites were investigated by Scanning Electron Microscopy.     

硅烷表面修饰氧化铝对聚丙烯的力学和耐热性能的影响

以3%氧化铝(Al2O3)或3种硅烷偶联剂表面修饰过的氧化铝为增强剂,采用高速混合与熔融挤出结合方法制备Al2O3/聚丙烯(PP)复合材料。研究硅烷表面修饰氧化铝对PP力学性能和耐热性能的影响。结果表明,采用硅烷偶联剂γ-巯丙基三甲氧基硅烷(KH590)对氧化铝表面修饰后,Al2O3/PP复合材料的性能得到改善。拉伸强度由33.80 MPa略降至32.63 MPa,冲击强度由14.58 kJ/m2增加至19.79 kJ/m2,拉伸模量由0.25 GPa增加至0.27 GPa,邵氏硬度D由75增加到84;同时Al2O3/PP复合材料的耐热性能有明显提高。     

Effects of poly(butylene succinate) and ultrafine wollastonite on the physical properties of plasticized poly(vinyl chloride)

In this study, diisononyl phthalate (DINP), a conventional plasticizer of poly(vinyl chloride) (PVC), was partially replaced by a polymeric plasticizer, poly(butylene succinate) (PBS), in order to reduce the leaching out of low‐molecular‐weight plasticizer from the plasticized PVC. Samples were prepared by melt mixing on a two‐roll mill followed by compression molding into a 3‐mm thick sheet. The DINP/PBS‐plasticized PVC provides a dose‐dependent increase in the tensile properties (tensile strength, Young's modulus, and elongation at break), tear strength, and thermal stability, as compared with the DINP‐plasticized PVC. According to the overall properties, PVC plasticized with 10/30 phr (parts by weight per hundred parts of resin) DINP/PBS was selected for preparing composites with varied loadings of an ultrafine wollastonite (particle size of 1,200 mesh). Their tensile properties, tear strength, thermal stability, and morphology were evaluated and compared with the 40 phr of DINP‐plasticized PVC composites. The results showed an increase in the Young's modulus and thermal stability but a decrease in the tensile strength, elongation at break, and tear strength of either 40 phr of DINP‐ or 10/30 phr of DINP/PBS‐plasticized PVC composites. Therefore, the products may be useful where the dimensional and thermal stability of the plasticized PVC are needed. J. VINYL ADDIT. TECHNOL. 21:220–227, 2015. © 2014 Society of Plastics Engineers     

高性能纳米TiO2／HIPS复合材料的研制

采用溶胶－凝胶法制备纳米TiO2,并对纳米TiO2进行表面处理,在大分子分散剂存在下,通过母料法工艺制备了纳米TiO2/HIPS复合材料。实验结果表明,制备的纳米TiO2/HIPS复合材料的缺口冲击强度、拉伸强度和弹性模量在纳米TiO2含量为2％时上升为最大值,且复合材料的硬度、耐热性能、阻燃性能随纳米TiO2含量的增加而提高。     

Synthesis of montmorillonite-modified acrylic impact modifiers and toughening of poly(vinyl chloride)

A series of Na-montmorillonite (Na⁺-MMT) modified acrylic impact modifiers (mAIM) were prepared by seeded emulsion polymerization. These mAIM modifiers were characterized by XRD. A 0.24?nm of increased interlayer distance of Na⁺-MMT was an indication of polymer chains intercalation within interlayer spacing. The notched Izod impact tests proved that the impact strength of the PVC/AIM composites prepared by melt blending was 43?J/m, markedly higher than the impact strength of pure PVC. Furthermore, with increasing content of AIM, the composites exhibited changes from brittle fracture to ductile fracture, with the impact strength increasing from 200 to about 1,000?J/m. The impact strength of PVC/mAIM also showed the same trend, although there were drops in some values. The impact strength of PVC/mAIM composites decreased with the increases in Na⁺-MMT content, but the yield strength and modulus of the composites increased with higher Na⁺-MMT content. The result also showed that the tensile strength of mAIM with 2 wt?% Na⁺-MMT is lower than that of mAIM with 0.8 and 1 wt?% contents, but still sufficiently large in comparison to the tensile strength of mAIM with 0 wt?% Na⁺-MMT. The dynamic mechanical analysis (DMA) result showed that the glass transition temperature (T _g) of mAIM did not show obvious changes and the elasticity of mAIM was reduced with the additional Na⁺-MMT content.     

改性纳米CaCO3/PVC复合材料的力学性能

采用钛酸酯偶联剂和PMMA接枝方法改性纳米碳酸钙,并采用熔融共混法制备了改性纳米CaCO3增韧PVC（CaCO3／PVC）复合材料,研究了复合材料的力学性能。对比于未处理纳米CaCO,和钛酸酯偶联剂处理纳米CaCO3,PMMA接枝聚合改性纳米CaCO3与基体的相容性最好,增韧PVC复合材料的拉伸强度得到较大幅度提高。