玻璃纤维增强尼龙66复合材料的结构与性能

使用双螺杆挤出机,采用共混改性方法制备玻璃纤维(GF)增强尼龙66(PA 66)复合材料(GF-PA 66),并对其结构、热性能和力学性能进行了表征。结果表明:制备的GF质量分数分别为20%,25%,30%的GF-PA 66复合材料的密度均低于1.4 g/cm~3,GF在GF-PA 66复合材料体系中呈现纤维交错复杂的网络结构;GF-PA 66复合材料的起始热降解温度均在320℃以上,具有较好的耐热性;随着GF含量的增加,GF-PA 66复合材料的拉伸强度、弯曲强度、弯曲模量升高,当GF质量分数达到30%时,复合材料的拉伸强度为147.4 MPa,比纯PA 66提高了75%,弯曲强度达到202 MPa,比纯PA 66提高了112%,弯曲模量达到7 783.3 MPa,比纯PA 66提高了175%;随着GF含量的增加,GF-PA 66复合材料的悬臂梁冲击强度先降低后升高,当GF质量分数为30%时,复合材料的悬臂梁冲击强度高于纯PA 66。     

聚氨酯/玻璃纤维复合绝缘子芯棒的制备

以耐酸无碱玻璃纤维(GF)为增强体、高韧性聚氨酯(PUR)树脂为基体,利用快速注射拉挤成型工艺制备了PUR/GF复合材料.重点研究了GF含量对PUR/GF复合材料弯曲强度、拉伸强度和断裂韧性及其微观结构的影响,同时考察了该复合材料的电气性能,验证了PUR/GF复合材料作为复合绝缘子芯棒的适用性.结果表明,当GF质量分数为79.7％时,PUR/GF复合材料的拉伸强度和断裂韧性综合性能最优,此时PUR/GF复合材料的拉伸强度为1 330 MPa,冲击强度高达450 kJ/m2,电气性能满足±500 kV直流棒形悬式复合绝缘子技术条件,PUR/GF复合芯棒综合性能优于传统环氧树脂芯棒.其生产效率高、制造成本低,有望作为潜在的电力行业复合绝缘子芯棒的替代材料.     

高压CO_2流体发泡制备微孔PVC/PUR–T泡沫材料

以聚氯乙烯(PVC)、热塑性聚氨酯弹性体(PUR–T)为原料,通过溶液共混方法,用四氢呋喃(THF)溶解混合物,浇涛在聚四氟乙烯模具中制得PVC/PUR–T共混材料,采用高压CO_2为发泡剂用间歇发泡法制备PVC/PUR–T发泡共混材料。通过对解吸附时间的测定,确定了饱和时间为24 h。通过改变饱和压力得到一系列不同体积膨胀倍率和泡孔大小的材料,随着PUR–T含量的增加,体积膨胀倍率呈下降的趋势;PUR–T含量为5%时,混合材料的泡孔密度最大,随后又会降低,同时随着饱和压力的提高,试样的泡孔密度随之变大。在对发泡样品进行力学性能测试时,发现加入5%的PUR–T对断裂伸长率影响不大,但随着PUR–T含量的增加,断裂伸长率增加;随着PUR–T含量的增加,发泡共混物的拉伸强度也增加,说明PUR–T的加入增强了体系的强度和韧性。     

GF及偶联剂改性PVC/稻壳木塑复合材料

采用模压成型的方式、通过实验探索玻璃纤维(GF)含量及偶联剂处理对聚氯乙烯(PVC)/稻壳木塑复合材料的力学特性和耐磨性的影响。实验结果表明:PVC/稻壳木塑复合材料的硬度随GF含量增加呈现先减小后增大的趋势。GF含量在15%以下时,随着GF用量的增大,木塑复合材料的拉伸强度与冲击强度总体上随之变大,超过15%则随GF含量增大而减小。而弯曲强度出现先减后增的趋势,弯曲弹性模量则与之相反。木塑复合材料的耐磨损性在GF含量为15%时最佳,摩擦系数在10%时最大。合适的偶联剂处理能增强木塑复合材料的力学性能和耐磨性。其中γ–氨丙基三乙氧基硅烷(KH550)的增强效果比较好,钛酸酯不能提高PVC/稻壳木塑材料的力学性能和耐磨性。     

改性EP/S–GF单向复合材料缠绕成型工艺及性能

以4,4’-二氨基二苯甲烷、苯酚和甲醛为原料合成二胺型苯并恶嗪(MDA–BOZ),并用其改性环氧树脂(EP)。采用湿法缠绕成型方法制备单向高强玻璃纤维(S–GF)增强改性EP基复合材料。用T–β外推法和凝胶化时间法确定了复合材料的成型工艺,并测试了其在室温和高温下的拉伸强度、弯曲强度、层间剪切强度等力学性能。与EP/4,4’–二氨基二苯砜(DDS)/S–GF复合材料相比,EP/MDA–BOZ/DDS/S–GF复合材料综合力学性能有较大提高。EP/MDA–BOZ/DDS/S–GF复合材料室温弯曲强度达1 428.3 MPa,层间剪切强度达79.92 MPa,纵向拉伸强度1 134.1 MPa,拉伸弹性模量为40.15 GPa。复合材料在100℃时,弯曲强度保持率为78.95%,层间剪切强度保持率为81.06%。扫描电子显微镜分析发现,改性树脂与玻璃纤维界面粘结性较好。     

不同造粒尺寸PEEK/GF复合材料性能研究

采用质量份数比为30∶70的连续玻璃纤维(GF)与聚醚醚酮(PEEK)制备了长度分别为4mm,8mm和12mm的3种不同造粒尺寸PEEK/GF复合材料,研究了不同造粒尺寸对复合材料力学性能及熔融结晶行为的影响,并用扫描电子显微镜观察其断面形貌。结果表明:随着造粒尺寸的增加,GF的剩余长度增加,复合材料储能模量降低,损耗因子(tanδ)降低,力学性能小幅度提高;当造粒尺寸为12mm时,复合材料拉伸强度和弯曲强度分别提高了2.13MPa,1.74MPa,断裂伸长率提高了2.86%,综合力学性能最佳。     

玻璃纤维改性酚醛泡沫塑料的研究

采用玻璃纤维(GF)改性酚醛(PF)泡沫塑料,考察了其阻燃性能、表观密度和力学性能。阻燃性能测试结果表明,GF的加入进一步提高了PF泡沫塑料的阻燃性能。表观密度测试结果表明,PF泡沫塑料的表观密度随着GF含量的增加而增大。力学性能测试结果表明,当GF长度为3 mm、质量分数在10%以内时,随着GF含量的增加,PF泡沫塑料的压缩强度和弯曲强度都有所提高;当GF质量分数超过10%后,随着GF含量的增加,PF泡沫塑料的压缩强度和弯曲强度逐渐降低。当GF质量分数为6%时,随着GF长度的增加,PF泡沫塑料的压缩强度有所降低,弯曲强度略有增加。当GF质量分数为6%、长度为3 mm时,PF泡沫塑料的的极限氧指数为48%,表观密度为50 kg/m3,压缩强度为0.30 MPa,弯曲强度为0.34 MPa,综合性能较好。     

螺杆转速对PP/GF复合材料中GF与性能的影响

研究了同向双螺杆造粒机组的螺杆转速对GF增强聚丙烯(PP/GF)复合材料中GF含量、长度以及复合材料力学性能的影响。结果表明,随着螺杆转速的提高,复合材料中GF的含量不断增加,最多增加了48.2%,而其长度却逐渐变短;复合材料的拉伸强度、弯曲强度、耐热性、硬度等性能也随着螺杆转速的增加而提高,冲击强度却逐渐下降;随着马来酸酐官能化聚丙烯的引入,GF的含量提高了1.8%,纤维长度显著增加且明显改善了复合材料的各项力学性能,其中拉伸强度提高了95.1%,弯曲强度提高了90.1%,无缺口冲击强度提高了110.4%,缺口冲击强度提高了50%。     

组分对PC/PBT/GF三元复合材料的影响

通过双螺杆挤出机制备了聚碳酸酯(PC)/聚对苯二甲酸丁二酯(PBT)/玻璃纤维(GF)三元复合材料,研究了PC,PBT,GF以及增容剂的含量对复合材料的影响。结果表明,在PC/PBT体系中,当PC∶PBT=7∶3时复合材料可以达到较好的刚韧平衡,拉伸强度为71.6 MPa,缺口冲击强度为10.21 kJ/m~2;在PC/PBT/GF复合材料中GF可以起到异相成核的作用,提高了复合材料的结晶速度,随着GF含量的增加,弯曲强度逐渐增加,拉伸强度先上升后下降,缺口冲击强度先下降后上升;增容剂KH–550,AX8900以及PTW均能改善PC/PBT/GF三元复合材料的相容性,其中AX8900增容效果最佳,从力学性能表明,加入1%的AX8900,PC/PBT/GF复合材料的性能最平衡,弯曲弹性模量和缺口冲击强度分别是没有添加增容剂的1.13倍和2.11倍。     

碳纤维增强聚氨酯弹性体复合材料的研究

为了制备具有优良导热性能、耐热性能和力学性能的新型聚氨酯(PUR)弹性体复合材料,采用预聚体法以聚四氢呋喃醚二醇(PTMG),2,4-甲苯二异氰酸酯(TDI)和碳纤维(CF)粉末为原料,制备了不同CF含量的CF增强PUR弹性体复合材料。对其进行了导热性能、耐热性能和力学性能测试,并通过扫描电子显微镜考察了CF在PUR基体中的分散状态。红外测试结果表明,CF表面含有可以与PUR基体发生反应的—OH和—COOH。当CF质量分数为0.3%时,CF可以均匀地分散在PUR基体中,CF增强PUR弹性体复合材料的拉伸强度、撕裂强度、100%和300%定伸强度、玻璃化转变温度和热导率分别为42.24 MPa,94.03 k N/m,9.33 MPa,24.87 MPa,96.7℃和0.138 5 W/(m·K),比纯PUR弹性体分别提高了27.8%,32.2%,76.4%,102.2%,18.5℃和26.4%,而断裂伸长率为367.62%,仅下降19.5%。     

废弃环氧模塑料填充聚氯乙烯的研究

用废弃环氧模塑料粉作为填料,采用模压成型的方法制备了聚氯乙烯（PVC）/废弃环氧模塑料复合材料,研究了废弃环氧模塑料粉的组成和性质及其与PVC的界面黏结情况,分别考察了温度和废弃环氧模塑料粉含量对复合材料力学性能和动态力学性能的影响。结果表明,废弃环氧模塑料粉具有一定的活性,能与极性树脂PVC发生作用而产生界面接枝;在模压温度为200 ℃,废弃环氧模塑料粉含量为60 %（质量分数,下同）时,复合材料的拉伸强度为32.13 MPa,弯曲强度和冲击强度分别为60.70 MPa和4.68 kJ/m2,基本可满足相关产品的要求;随着废弃环氧模塑料粉含量的增加,复合材料的储能模量提高,损耗峰向高温方向移动,且损耗峰形先变宽后变窄。     

马来酸酐接枝天然橡胶在废报纸粉填充聚氯乙烯材料中的应用

研究了马来酸酐接枝天然橡胶（MNR）作为改性剂，对废报纸粉（PF）填充聚氯乙烯（PVC）复合材料的力学性能和热学性能的影响。研究结果表明，MNR可以较好地改善PF与PVC基体的相容性，显著提高材料的冲击强度。当PF用量（质量份）为5份、MNR为4份时PF／PVC复合材料的综合性能最好，其拉伸强度为48．8MPa，缺口冲击强度达10．1kJ／m^2，后者比改性前提高了87％。热重分析表明：PF／MNR／PVC复合材料的耐热性比纯PVC树脂有所提高。而PF／PVC复合材料的维卡软化温度随着PF填充量的增加而提高，但随着MNR的增加而略有降低。冲击断面扫描电镜分析证实MNR改善了报纸粉与基体树脂的相容性。     

Mechanical and morphological properties for sandwich composites of wood/PVC and glass fiber/PVC layers

This work manufactured sandwich composites from glass fiber/poly(vinyl chloride) (GF/PVC) and wood/PVC layers, and their mechanical and morphological properties of the composites in three GF orientation angles were assessed. The effects of K value (or viscosity index) of PVC and Dioctyl phthalate (DOP) loading were of our interests. The GF/PVC was used as core layer whereas wood/PVC was the cover layers. The experimental results indicated that PVC with low K value was recommended for the GF/PVC core layer for fabrication of GF/WPVC sandwich composites. The improvement of PVC diffusion at the interface between the GF and the PVC core layer was obtained when using PVC with K value of 58. This was because it could prevent de‐lamination between composite layers which would lead to higher mechanical properties of the sandwich composites, except for the tensile modulus. The sandwich composites with 0° GF orientation possessed relatively much higher mechanical properties as compared with those with 45° and 90° GF orientations, especially for the impact strength. Low mechanical properties of the sandwich composites with 45° and 90° GF orientation angles could be overcome by incorporation of DOP plasticizer into the GF/PVC core layer with the recommended DOP loadings of 5–10 parts per hundred by weight of PVC components. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

增容剂对PVDF/PUR-T复合材料的性能影响

采用流延成膜法制备了硅烷偶联剂KH–560和端氨基液体丁腈橡胶(ATBN)协同改性的聚偏氟乙烯(PVDF)/聚醚型热塑性聚氨酯弹性体(PUR–T)复合材料,初步探讨了单一增容剂(KH–560或ATBN)含量、复配增容剂含量与比例及成膜温度等条件对PVDF/PUR–T复合材料力学性能的影响,深入研究了复合材料的结晶性能、热稳定性能和亲/疏水性能。结果表明,与单一增容剂相比,复配增容剂的引入明显提高了复合材料的力学性能,并且当复配增容剂添加量为10%,复配比KH–560/ATBN=3/1,成膜温度为50℃时,其与PVDF/PUR–T基体间的界面粘结性明显得到改善,改性后复合材料断裂伸长率达到273%。PUR–T与复配增容剂的加入抑制了PVDF的结晶,复合材料的结晶度降低,但仍具有良好的热稳定性能,且疏水性得到提高。     

PUR-T／PVC热塑性弹性体的制备及工艺探究

以热塑性聚氨酯弹性体(PUR–T)、聚氯乙烯(PVC)为主要原材料,通过熔融共混挤出制备PUR–T／PVC共混热塑性弹性体。讨论了PUR–T／PVC共混比、增塑剂用量、挤出共混温度、螺杆转速对共混弹性体性能的影响,利用万能试验机、扫描电子显微镜、转矩流变仪、旋转流变仪等研究了弹性体的加工性能及结构。结果表明,当PUR–T／PVC共混比为70／30,增塑剂邻苯二甲酸二辛酯用量为20份,挤出温度为160℃,螺杆转速为330 r／min时,弹性体材料的综合性能最佳;共混弹性体的表观黏度小于纯PUR–T,PVC含量在20%～50%时,PVC易形成网络结构。     

Simultaneous toughening of PPO/HIPS/Glass fiber reinforced composites with thermoplastic rubbers

Simultaneously reinforced and toughened PPO/HIPS/SEBS/glass fiber (GF) 60/40/5/30 composites were successfully prepared with GF as reinforcing agent and SEBS as toughener. The formulation of PPO/HIPS/SEBS/GF quaternary composites was stepwise optimized by evaluating the effect of GF and SEBS on the processing, mechanical and thermal properties of the composites. The synergistic effects of GF reinforcement and elastomer toughening are attributed to high performance PPO/HIPS/SEBS/GF composites. Among the four elastomers studied, SEBS exhibited as effective toughener for PPO/HIPS matrix and the resulted PPO/HIPS/SEBS/GF composites presented a good combination of mechanical and thermal properties. The optimized PPO/HIPS/SEBS/GF 60/40/5/30 quaternary composites displayed a tensile strength of 123.6 MPa, a bending strength of 149.7 MPa, an unnotched impact strength of 46.6 KJ/m² and a heat distortion temperature of 148.9°C. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40299.     

Polyurethane Composites Reinforced with Walnut Shell Filler Treated with Perlite,Montmorillonite and Halloysite

In the following study, polyurethane (PUR) composites were modified with 2 wt.% of walnut shell filler modified with selected mineral compounds–perlite, montmorillonite, and halloysite. The impact of modified walnut shell fillers on selected properties of PUR composites, such as rheological properties (dynamic viscosity, foaming behavior), mechanical properties (compressive strength, flexural strength, impact strength), dynamic-mechanical behavior (glass transition temperature, storage modulus), insulation properties (thermal conductivity), thermal characteristic (temperature of thermal decomposition stages), and flame retardant properties (e.g., ignition time, limiting oxygen index, heat peak release) was investigated. Among all modified types of PUR composites, the greatest improvement was observed for PUR composites filled with walnut shell filler functionalized with halloysite. For example, on the addition of such modified walnut shell filler, the compressive strength was enhanced by ~13%, flexural strength by ~12%, and impact strength by ~14%. Due to the functionalization of walnut shell filler with thermally stable flame retardant compounds, such modified PUR composites were characterized by higher temperatures of thermal decomposition. Most importantly, PUR composites filled with flame retardant compounds exhibited improved flame resistance characteristics-in all cases, the value of peak heat release was reduced by ~12%, while the value of total smoke release was reduced by ~23%.     

Preparation and characterization of poly(vinyl chloride)–continuous carbon fiber composites

In this article, we report on the preparation and characterization of novel poly(vinyl chloride) (PVC)–carbon fiber (CF) composites. We achieved the reinforcement of PVC matrices with different plasticizer contents using unidirectional continuous CFs by applying a warm press and a cylinder press for the preparation of the PVC–CF composites. We achieved considerable reinforcement of PVC even at a relatively low CF content; for example, the maximum stress (σ_max) of the PVC–CF composite at a 3% CF content was found to be 1.5–2 times higher than that of the PVC matrix. There were great differences among the Young's modulus values of the pure PVC and PVC–CF composites matrices. The absolute Young's modulus values were in the range 1100–1300 MPa at a 3% CF content; these values were almost independent of the plasticizer content. In addition, we found a linear relationship between σ_max and the CF content and also recognized a linear variation of the Young's modulus with the CF content. The adhesion of CF to the PVC matrix was strong in each case, as concluded from the strain–stress curves and the light microscopy and scanning electron microscopy investigations. The mechanical properties of the PVC–CF composites with randomly oriented short (10 mm) fibers were also investigated. At low deformations, the stiffness of the composites improved with increasing CF content. Dynamic mechanical analysis (DMA) was used to determine the glass‐transition temperature (T_g) of the PVC–CF composites. The high increase in the Young's modulus entailed only a mild T_g increase. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012