Thermal conductivity of several geopolymer composites and discussion of their formulation

We fabricated 50.8-mm cube-shaped samples of metakaolin geopolymer (GP) composites with various additives chosen to increase or decrease the thermal conductivity of the composite. Sodium-based GP (NaGP) and GP composites were more conductive than potassium-based GP (KGP) composites for a given phase fraction of filler, but the maximum amount of filler phase was higher with KGP due to the lower viscosity of the KGP mixture. The highest thermal conductivity achieved was about 8 W/m K by KGP + 44-vol% graphite flakes, whereas NaGP + 27 vol% graphite flakes reached 4.7 W/m K. The thermal conductivity was strongly affected by the moisture remaining in the composite, which appeared to have a greater effect at higher filler content. On the other hand, the size of alumina particles (6, 40, or 120 μm) did not have any apparent effect on thermal conductivity for the same filler content. Larger particles caused less change in mixture viscosity, though, thus permitting incorporation of higher filler phase fractions and therefore higher thermal conductivity.     

离子液体改性石墨烯的制备及其对ABS复合材料导热性能的影响

合成了一种氨基功能化离子液体[HAIM]BF4,并将其应用于石墨烯的改性。通过绿色直接的球磨法,将G粉与1-己基-3-氨乙基咪唑四氟硼酸离子液体[HAIM]BF4相结合,制备出离子液体功能改性石墨烯（G@ILs）。所得G@ILs使用熔融共混法加入丙烯腈-丁二烯-苯乙烯共聚物（ABS）中,制备G@ILs/ABS复合材料。使用X射线衍射分析（XRD）,X射线光电子能谱（XPS）,扫描电子显微镜（SEM）,透射电子显微镜（TEM）和拉曼测试等多种手段对G@ILs的结构和性质进行分析。结果表明,[HAIM]BF4通过阳离子-π相互作用对石墨烯进行了有效修饰,保持了石墨烯的结构完整性。由于G@ILs的独特性能,G@ILs/ABS复合材料在机械性能方面表现出相当大的改善。加入1 wt.%G@ILs的G@ILs/ABS复合材料的拉伸强度和弯曲模量为42.4 MPa和2145.1 MPa,比ABS提高了8.36%和12.76%。此外,在加入1 wt.%G@ILs的G@ILs/ABS复合材料的导热系数为0.249 W·m-1·k-1,比纯ABS提高了21.5%。     

导热型环氧复合材料的研究进展

介绍了导热型环氧复合材料导热性能和导热机理。并综述各类导热环氧复合材料的研究进展,在此基础上讨论提高复合材料导热性能的途径。     

环氧树脂/玻璃布/BN导热复合材料的制备与性能研究

采用高温模压成型法制备环氧树脂(EP)/玻璃布/氮化硼(BN)导热复合材料。探讨了BN用量和偶联剂处理对复合材料力学性能、导热性能和介电性能等影响。结果表明:当w(BN)=15%时,复合材料的冲击强度较高;导热性能随着BN用量的增加而增大;当w(BN)=25%时,改性复合材料的热导率为0.901 2 W/(m.K),此时复合材料仍保持较低的介电常数和介电损耗。当BN用量相同时,偶联剂表面处理可有效改善复合材料的力学性能和导热性能。     

ABS树脂耐热性的研究进展

介绍了国内外ＡＢＳ 树脂耐热性改善研究进展,并提出了进一步开发深加工产品建议。     

环氧树脂/ABS复合材料的制备及性能表征

以环氧树脂为基体,苯乙烯-丙烯腈-丁二烯（ABS）树脂为增韧剂,制备了环氧树脂/ABS复合材料,讨论了增韧剂对复合材料的热性能和机械性能的影响。结果表明,ABS的添加可提高复合材料的断裂韧性。扫描电镜结果显示,基体的剪切屈服和橡胶颗粒的微孔洞是ABS增韧环氧树脂的主要增韧机理。     

耐高温高导热环氧树脂／玻纤／BN复合材料的制备

以4,4-二氨基二苯砜（DDS）和内亚甲基四氢邻苯二甲酸酐（NA）为复配固化剂,采用高温模压成型法制备耐高温高导热环氧树脂／玻纤／氮化硼（BN）复合材料。探讨了BN用量和偶联剂处理对复合材料冲击强度、导热性能和电阻率的影响。结果表明：当nDDS：nNA=3：1时,复合材料的耐热性能最佳。当BN质量分数为8％时,复合材料的冲击强度最高;导热性能随BN用量的增加而增加,当BN用量为15％时,热导率为0．7560W／（mk）,此时复合材料仍保持较高的体积、表面电阻率;当BN填充量为一定值时,偶联剂处理使冲击强度和导热性能得到进一步提高。     

聚合物基导热复合材料的研究进展

阐述了聚合物基导热复合材料的导热机制。综述了国内外导热胶粘剂、导热橡胶和导热塑料等研究进展。介绍了提高复合材料导热性能的途径,并在此基础上,展望了聚合物基导热复合材料的应用前景和未来的发展方向。     

环氧树脂/玻纤/BN导热绝缘复合材料制备研究

采用高温模压成型法制备环氧树脂/玻纤/BN导热复合材料,探讨了BN用量对复合材料力学性能、导热性能和电性能的影响,结果表明.当BN用量为10%时,复合材料的冲击强度和弯曲强度较佳;导热性能随BN用量的增加而提高,当BN用量为20%耐.热导率为0.7438 W/mk,此时复合材料仍保持较好的绝缘性能.     

耐热ABS树脂的制备

采用乳液聚合法合成了一系列N-苯基马来酰亚胺（NPMI）-苯乙烯（St）-丙烯腈（AN）共聚物（简称SMIA树脂）,将其与AN-丁二烯-St三元共聚物（ABS）熔融共混制备了耐热ABS树脂。采用傅里叶变换红外光谱、差示扫描量热法对SMIA树脂进行了表征,探讨了SMIA树脂组成对ABS树脂性能的影响。结果发现：NPMI的引入可以显著提高ABS树脂的耐热性能,当w（NPMI）为10％～20％、m（St）／m（AN）为70：30时,ABS树脂既具有较高的玻璃化转变温度,又具有较好的力学性能。     

天然鳞片石墨/环氧树脂复合材料的制备及导热性能研究

以天然鳞片石墨为导热填料,E44型环氧树脂为基体,采用超声分散法制备天然鳞片石墨/环氧树脂复合导热材料.系统考察了天然鳞片石墨用量、石墨粒度和炭黑添加量等因素对复合材料导热性能的影响.结果表明:随着天然鳞片石墨用量增加,复合材料的导热系数增大,抗压强度先增加后减小;复合材料的导热系数随天然石墨粒径的增大而增大,抗压强度先减小后增加;在石墨/环氧树脂复合导热材料中添加不同用量的炭黑时,随着炭黑添加量的增加,复合材料的抗压强度增大,导热系数先增大后减小.制备天然鳞片石墨/环氧树脂复合导热材料的最佳配方为天然鳞片石墨用量45％,粒径≤270 μm,炭黑用量2％.     

Mechanical and thermal properties of ABS and leather waste composites

To determine the possibility of using leather waste as reinforcing filler in the thermoplastic polymer composite, acrylonitrile–butadiene–styrene (ABS) as the matrix and leather buffing powder as reinforcing filler were used to prepare a particulate reinforced composite to determine testing data for the physical, mechanical, and thermal properties of the composites, according to the filler loading in respect to thermoplastic polymer. The ABS and leather powder composites were prepared by the extrusion of ABS with 2.5, 5, 7.5, 10, 12.5, and 15 wt % of leather powder in corotating twin screw extruder. The extruded strands were cut into pellets and injection molded to make specimens. These specimens were tested for physicomechanical properties like tensile and flexural strengths, tensile and flexural modulus, Izod and charpy impact strength, abrasion resistance, Rockwell hardness, density, Heat deflection temperature (HDT) and Vicat softening point (VSP), water absorption, and thermal degradation analysis. The incorporation of leather waste powder does not affect the tensile, flexural strengths, Izod impact strength, abrasion resistance, Rockwell hardness, density, HDT and VSP values drastically. However, the tensile modulus, tensile elongation, and charpy impact strength values are reduced significantly. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3062–3066, 2006     

PE-XC材料导热系数的测量

文章采用瞬态热线法测试PE材料的导热系数,介绍了瞬态热线法的优势,并使用TC3000导热系数仪更加快捷、精确、高效的测试PE材料的导热系数。     

Evaluation of thermal conductivity and esthetic quality of denture base resin composites with acrylic polymer and nanodiamonds

The effect on the thermal conductivity and esthetic quality of acrylic denture base resins due to the addition of surface-carboxylated nanodiamonds (NDs) was evaluated using direct heat flux measurement and spectrophotometric measurement, respectively. The addition of NDs to the denture resin improved its thermal conductivity, which was highly depended on the ND content. The thermal conductivity increased significantly upon the addition of a small amount of NDs, followed by a gradual decrease with increasing ND content. The influence of the ND content on the thermal conductivity of the ND-impregnated resins was explained via experimental results and the theory of phonon scattering. Furthermore, changes in the appearance of the denture base resins caused by ND impregnation were observed to assess their esthetic qualities. The color changes in the resins with low ND contents were found to be minor. Therefore, the improved thermal conductivity and the retention of appearance of the resin can be simultaneously achieved by the addition of a small amount of NDs.     

2012年ABS树脂生产与市场分析

综述了2012年国内外ABS(丙烯腈-丁二烯-苯乙烯)树脂生产商的生产能力和实际产量、国内外ABS市场和价格,对国内ABS树脂技术现状及其市场发展趋势进行了分析和预测。另外,还介绍了国内外科研开发、技术进展以及新产品开发情况,并针对国内ABS树脂装置提出了几点建议。     

ABS及其复合材料的热性能研究

通过熔融共混法制备了ABS、ABS/MH(氢氧化镁)及ABS/MH/BPS(溴化聚苯乙烯)/Sb2O3(氧化锑)阻燃复合材料。使用扫描电子显微镜(SEM)观察了燃烧样条的表面形貌,利用热重分析法(TG)研究了不同升温速率下复合材料的热降解过程,分析了其阻燃机理。结果表明:MH可以增加体系的热稳定性,而加入BPS/Sb2O3会使热稳定性降低;MH和BPS/Sb2O3共同阻燃时,Br-Sb阻燃体系占主导地位,在气相中发挥阻燃效果,MH则在凝聚相起辅助作用,产生物理隔绝和阻止熔融流动的效果。     

Thermal conductivity and diffusivity of carbon-reinforced polyetherketoneketone composites

Heat transfer properties play an important role in processing of polyetherketoneketone (PEKK)/carbon fiber (CF) composites. Accordingly, thermal conductivity and diffusivity of PEKK, PEKK/glassy carbon (GC), and PEKK/CF composites have been studied. Observed increase in conductivity and diffusivity with carbon filler addition was analyzed using the Maxwell–Eucken model. PEKK/GC composites with low carbon fraction indicated good fitting experimental points of the model, indicating good dispersion of particles. For PEKK/CF composites, the thermal conductivity and diffusivity increase is a reflection of a decrease in porosity. Results as observed from the model points to a homogenous dispersion within the PEKK/CF composites as well. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47975.     

ABS树脂市场分析及预测

综述了2008年国内外ABS树脂生产商的生产能力和实际产量、国内外ABS市场和价格，对国内ABS技术现状及其市场发展趋势进行了分析和预测。另外，还介绍了国内外科研开发、技术进展以及新产品开发情况，并针对国内ABS装置提出了几点建议。     

ABS树脂国内外市场分析及预测

综述了国内外ABS树脂生产商的生产能力和实际产量、国内外ABS市场和价格,对国内ABS技术现状及其市场发展趋势进行了分析和预测。另外,还介绍了国内外科研开发、技术进展以及新产品开发情况,并针对国内ABS装置提出了几点建议。     

ABS树脂阻燃剂的研发进展

介绍了ABS树脂阻燃剂的研究开发进展,指出了其今后的发展趋势。