含氟聚醚醚酮增韧环氧树脂相形貌与性能研究

采用SEM观察了热塑性含氟结构聚醚醚酮(6FPEEK)共混增韧环氧树脂的浇铸体脆断断口相形貌,测试了浇铸体的力学性能及动态机械性能,通过统计和数学分析建立了冲击韧性(αk)、热塑颗粒粒径(d)和粒间距(D)间的半定量关系。结果表明,该体系可得到连续相为环氧树脂而分散相为热塑颗粒的相结构,热塑相颗粒尺寸较为统一,且随热塑性树脂含量的增加而增大;6FPEEK含量增加对拉伸强度的影响不大,环氧树脂和热塑性塑料的结合界面差导致了冲击韧性在6FPEEK质量分数达到9.09%时出现峰值而后下降;该增韧体系的增韧机理可能为刚性粒子增韧。     

溶聚丁苯橡胶/炭黑/短纤维多相复合材料的动态力学性能

研究了短纤维用量和黏合水平、测试温度及频率对溶聚丁苯橡胶（SSBR）／炭黑／短纤维复合材料（SFRC）动态力学性能的影响。结果表明,SFRC的储能模量（E’）随短纤维用量的增加而增大;填充预处理短纤维的SFRC的E’大于填充同种未处理短纤维的SFRC,损耗因子（tanδ）则是后者大于前者（填充20份尼龙短纤维的SFRC除外）。与相同填充量的纯炭黑硫化胶相比,短纤维部分取代炭黑后,硫化胶在大于15℃时的E’增大（填充未处理聚酯短纤维的SFRC除外）,tanδ减小;SFRC的E’和tanδ随频率的增加而增大,但频率为50～100Hz时,随着温度的升高,短纤维用量越高,SFRC的E’减小,且E。和tanδ受频率的影响越小。     

改性炭黑增强三元乙丙橡胶的力学性能与加工性能

研究了用甲基丙烯酸缩水甘油酯(GMA)、甲基丙烯酸-2-羟乙酯(HEMA)和N-羟甲基丙烯酰胺(NMA)3种单体改性炭黑增强三元乙丙橡胶(EPDM)的力学性能,并用橡胶加工分析仪分析了GMA、HEMA和NMA改性炭黑对EPDM未硫化胶的加工性能。结果表明,GMA、HEMA和NMA改性炭黑均改善了EPDM硫化胶的力学性能,当其用量分别为3.75,3,3份时,EPDM硫化胶的定伸应力、拉伸强度和撕裂强度达到最佳值;降低频率、提高应变或温度有利于改善改性炭黑增强EPDM的加工性能。     

紫炭黑／天然橡胶共混胶性能的研究

采用机械共混法,探讨了紫炭黑（PCB）用量以及紫炭黑经偶联剂Si69改性后对紫炭黑／天然橡胶共混胶力学性能和热稳定性的影响,通过扫描电子显微镜（SEM）观察紫炭黑／天然橡胶共混胶的分散情况和断面形貌。结果表明,紫炭黑能提高橡胶的力学性能和热稳定性,经硅烷偶联剂Si69改性处理的紫炭黑可提高共混胶的力学性能,当Si69的用量为紫炭黑质量的8％时,胶料的力学性能最佳,其拉伸强度达到29．48MPa。     

Processing and mechanical behavior of carbon black graded rubber compounds

Functionally graded rubber compounds (FGRCs) were prepared by construction based method. The matrix used was natural rubber (NR). Amorphous carbon black (N‐330) was used as grading material. The gradation of nanoparticles in a rectangular geometry comprised the variation of particle volume fraction along thickness direction. Its performance was evaluated for structural application through various mechanical and surface properties like tensile strength, modulus, tear strength, elongation at break, hardness, fracture surface by scanning electron microscopy, etc. At the same percentage of nanofiller loading, FGRCs show enhanced properties, i.e., modulus and tear strength (in some grades) compared to uniformly dispersed rubber compounds (UDRCs). Modulus of FGRCs, for a given particular stacking sequence of the layers, increases as much as by 275% compared to UDRCs. The ultimate properties like tensile strength and elongation at break made up for the modulus enhancement that decreases to as minimum as 50 and 80%, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Structural,mechanical, thermal,and electrical properties of carbon black reinforced polyester resin composites

Carbon black (CB) reinforced polyester resin (PR) composites (CPC) have been fabricated from mechanical mixtures of liquid PR and CB powder having 0–50 wt% CB contents and cured with 1% of methyl ethyl ketone peroxide at room temperature under a pressure of 50 MPa. The samples have been examined by the Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD) technique, scanning electron microscopy (SEM), mechanical test, micromechanical test, differential thermal analysis (DTA), and thermogravimetric analysis (TGA) and electrical test. FTIR spectra confirm the physical and chemical bond formations between CB and PR. XRD shows a very partial crystalline structure in cured PR and hexagonal structure in CB particles. SEM exhibits a clear dispersion of CB particles in PR matrix at lower loading and aggregates at higher loading. With the increase of fillers, while the tensile and flexural strengths of CPCs decrease, the Young's and tangent modulii increase by 80 and 100%, respectively. These increments are found consistent with the theoretical values. The degree of physical crosslinking between CB and PR as well as the aspect ratio of CB in CPCs are found to increase with the increase of filler. A remarkable increase in microhardness of about 61% at 50 wt% CB content is observed. The TGA represents that the thermal degradation temperature for pure PR is 373°C and that for CPC is 393°C. The dielectric constant of CPCs decreases with increasing frequency, whereas the ac‐ and dc‐ conductivities of CPC are found to increase with CB content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40421.     

Morphology,thermal, and mechanical properties of acrylonitrile–butadiene–styrene/carbon black composites

Acrylonitrile–butadiene–styrene (ABS) polymers are susceptible to degradation that increases the yellowness of the polymer, distorts the surface glossy, and affects the mechanical properties. One way to protect ABS against degradation is the addition of carbon black (CB) that can act as a stabilizer. In this work, CB was dispersed in ABS through melt‐compounding. Electron microscopy was used to study the morphology of the filled‐ and unfilled‐ABS, and revealed that the CB particles/aggregates were distributed within the styrene–acrylonitrile (SAN) phase and around the PB phase. The results of the Fourier transform infrared spectroscopy showed that upon processing of ABS, crosslinking in the polybutadiene (PB) phase was the governing degradation mechanism. Increasing the CB content resulted in increasing the heat stability of the ABS/CB compounds, which was confirmed by thermogravimetric analysis. The DTA results showed that the PB degradation peak occurring at about 395°C was disappeared by addition of CB. Impact strength test was performed to study the effect of CB on the toughness of ABS. Impact strength was reduced with increasing CB loading. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Hysteresis and strain-dependent dynamic mechanical properties of epoxidized natural rubber filled with surface-oxidized carbon black

High-temperature molding of a mixture of epoxidized natural rubber (ENR) and intermediate super abrasion furnace (ISAF) carbon black results in strong rubber–filler interaction, the extent of which is greater in the case of the oxidized grade of the carbon black. It has been observed that ENR is bonded to the filler surface through the formation of primary bonds, such as ester and phenolic ether. An extensive filler–filler network formation takes place through the hydrogen bonding between the active groups of the rubber and filler surface. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 723–730, 1998     

Mechanical and surface properties of polyurethane/fluorinated multi‐walled carbon nanotubes composites

To improve the mechanical and surface properties of poly(etherurethane) (PEU), multi‐walled carbon nanotubes (MWCNTs) were surface grafted by 3,3,4,4, 5,5,6,6,7,7,8,8,8‐tridecafluoro‐1‐octanol (TDFOL) (MWCNT‐TDFOL) and used as reinforcing agent for PEU. Fourier‐transform infrared spectroscopy revealed the successful grafting of MWCNTs. PEU filled with MWCNT‐TDFOL could be well dispersed in tetrahydrofuran solution, and tensile stress–strain results and dynamic mechanical analysis showed a remarkable increase in mechanical properties of PEU by adding a small amount of MWCNT‐TDFOL. Contact angle testing displayed a limited improvement (just 9°) in the hydrophobicity of PEU surface by solution blending with MWCNT‐TDFOL. However, a large improvement of surface hydrophobicity was observed by directly depositing MWCNT‐TDFOL powder on PEU surface, and the water contact angle was increased from 80° to 138°. Our work demonstrated a new way for the modification of carbon nanotubes and for the property improvement of PEU. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

炭黑在天然橡胶/溶聚丁苯橡胶硫化胶中的分散及其对性能的影响

考察了溶聚丁苯橡胶(SSBR)用量、炭黑的种类及用量对天然橡胶(NR)/SSBR硫化胶动态力学性能和力学性能的影响.结果表明,炭黑与SSBR的结合作用比与NR弱;随SSBR用量的增加,炭黑在NR/SSBR共混硫化胶中的分散性提高,Payne效应减弱,频率敏感性增强;随SSBR用量的增加,NR/SSBR共混硫化胶的拉伸强度和撕裂强度减小,扯断伸长率变化不大;而定伸应力则呈先减小后增大的趋势;随不同种类的炭黑在NR/SSBR硫化胶中分散性的提高,定伸应力呈上升趋势,损耗因子和压缩生热呈减小趋势.     

Dynamic percolation phenomenon of poly(methyl methacrylate)/surface fluorinated carbon black composite

The electrical resistivity of polymer filled with conductive filler, such as carbon black (CB) particles, is greatly decreased by incorporating the conductive filler. This is called the percolation phenomenon and the critical CB concentration is called the percolation threshold concentration (Φ*). For CB particle–filled insulating polymer composite at lower than Φ*, the conductive CB network is constructed in the polymer matrix when the composite is maintained at a temperature higher than the glass‐transition temperature or the melting temperature of the polymer matrix. This phenomenon is called dynamic percolation and the time to reach the substantial decrease in resistivity is called percolation time (t_p). To investigate the relationship between the dynamic percolation process and the surface state of CB particles, we used three kinds of carbon black particles such as original carbon black (CB0) and fluorinated carbon black (FCB010 and FCB025)–filled poly(methyl methacrylate) (PMMA). It was observed that the dynamic percolation curves for CB0‐filled PMMA and FCB‐filled PMMA composites shifted to a shorter percolation time with increases in both the annealing temperature and the filler concentration. However, the dynamic percolation curves of FCB‐filled PMMA showed a gradually decreasing trend compared to that of CB0‐filled PMMA composites. The activation energy calculated from an Arrhenius plot of the t_p against the inverse of the annealing temperature was decreased by surface fluorine treatment. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1151–1155, 2003     

淀粉/炭黑/丁苯橡胶复合材料的抗疲劳性能

采用乳液共混法,用少量淀粉等量替代炭黑,制备淀粉/炭黑/丁苯橡胶(SBR)复合材料,研究了淀粉用量对复合材料抗疲劳性能的影响。结果表明,当丁苯胶乳为100份、炭黑与淀粉的总量为50份时,淀粉最佳替代量为5～8份,在此条件下复合材料的抗疲劳性能大幅度提高;淀粉/炭黑/SBR复合材料的抗疲劳性能与硫化胶的抗切割性能、裤形撕裂强度以及损耗因子有一定的相关性。     

Dynamic mechanical properties of polycarbonate and acrylonitrile–butadiene–styrene copolymer blends

Blends of polycarbonate (PC) and poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS) with different compositions are characterized by means of dynamic mechanical measurements. The samples show phase separation. The shift in the temperatures of the main dynamic mechanical relaxation shown by the blend with respect to those of the pure components is attributed to the migration of oligomers present in the ABS toward the PC in the melt blending process. A comparison with other techniques (dielectric and calorimetric analysis) and the application of the Takayanagi three block model confirm this hypothesis. In all the studied blend compositions (ABS weight up to 28.6%) the PC appears as the matrix where a disperse phase of ABS is present. The scanning and transmission electron microscopy micrographs show that the size of the ABS particles increases when the proportion of ABS in the blend increases. The FTIR results indicate that the interaction between both components are nonpolar in nature and can be enhanced by the preparation procedure. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1507–1516, 2002     

溶聚丁苯橡胶/炭黑/短纤维复合材料的取向结构与力学性能

研究了溶聚丁苯橡胶(SSBR)／炭黑／短纤维复合材料(SFRC)的力学性能和短纤维在橡胶中的取向度及其黏合效果,分析了短纤维的黏合作用对复合材料应力．应变形为的影响。结果表明,短纤维的加入显著提高了SFRC的撕裂强度、10％定伸应力及邵尔A型硬度;短纤维用量小于30份时。2种预处理短纤维的取向度呈增长趋势,且尼龙短纤维的取向度明显高于聚酯短纤维;SFRC在平行方向上有不同程度的屈服现象,且添加聚酯短纤维的SFRC屈服应变及应力值小于添加尼龙短纤维的SFRC。SFRC在垂直方向没有应力屈服现象;预处理短纤维与橡胶的黏合效果优于未处理短纤维。     

Particle size distribution,mixing behavior,and mechanical properties of carbon black (high‐abrasion furnace)–filled powdered styrene butadiene rubber

High‐abrasion furnace black (HAF, grade N330)–filled powdered styrene butadiene rubber [P(SBR/HAF)] was prepared and the particle size distribution, mixing behavior in a laboratory mixer, and mechanical properties of P(SBR/HAF) were studied. A carbon black–rubber latex coagulation method was developed for preparing carbon black–filled free‐flowing, noncontact staining SBR powders, with particle diameter less than 0.9 mm, under the following conditions: carbon black content > 40 phr, emulsifier/carbon black ratio > 0.02, and coating resin content > 2.5 phr. Over the experimental range, the mixing torque τ_α of P(SBR/HAF) was not as sensitive to carbon black content and mixing temperature as that of HAF‐filled bale SBR (SBR/HAF), whereas the temperature build‐up ΔT showed little dependency on carbon black content. Compared with SBR/HAF, P(SBR/HAF) showed a 20–30% mixing energy reduction with high carbon black content (>30 phr), which confers to powdered SBR good prospects for internal mixing. Carbon black and the rubber matrix formed a macroscopic homogenization in P(SBR/HAF), and the incorporation step is not obvious in the internal mixing processing results in these special mixing behaviors of P(SBR/HAF). A novel mixing model of carbon black–filled powdered rubber, during the mixing process in an internal mixer, was proposed based on the special mixing behaviors. P(SBR/HAF) vulcanizate showed better mechanical properties than those of SBR/HAF, dependent primarily on the absence of free carbon black and a fine dispersion of filler on the rubber matrix attributed to the proper preparation conditions of noncontact staining carbon black–filled powdered SBR. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2494–2508, 2004     

无喷霜硫化体系中硫黄用量对三元乙丙橡胶/白炭黑硫化胶性能的影响

采用无喷霜硫黄硫化体系,考察了硫黄用量对三元乙丙橡胶(EPDM)/白炭黑(WCB)混炼胶硫化特性及硫化胶物理机械性能、耐热老化性能、动态力学性能和压缩永久变形的影响。结果表明,在硫黄用量为0.5~1.5份的条件下,随着硫黄用量的增加,EPDM/WCB混炼胶的硫化速率减慢,硫化胶的拉伸强度先升高后下降,当硫黄用量为1.00份时达到最大值(22.4 MPa),同时扯断伸长率和永久变形逐渐下降,邵尔A硬度升高;热空气老化后,硫化胶的拉伸强度、撕裂强度和硬度均提高,但扯断伸长率下降幅度较大;随着硫黄用量的增加,硫化胶的玻璃化转变温度向高温方向移动,损耗因子峰值先升高后下降,储能模量增大,压缩永久变形略有减小。     

Interfacial mechanical behavior of 3D printed ABS

We describe an experimental approach for characterizing the local mechanical behavior of acrylonitrile butadiene styrene (ABS) structures processed through fused deposition modeling. ABS test specimens processed in various build orientations were subject to multiscale mechanical tests as well as local morphology and chemical analyses. Instrumented indentation, local dynamic mechanical analysis, and atomic force microscopy tests were used to explore the mechanical behavior and morphology of build surfaces and weld interfaces. An interfacial stiffening effect was found for the majority of the specimens tested, with up to a 40% increase in the indentation elastic modulus measured with respect to the build surfaces. Raman spectroscopy mapping of the interfacial areas revealed ～30% less butadiene/styrene and butadiene/acrylonitrile ratios with respect to analysis of the build surfaces. The results provide insight into the multiscale behavior of additive manufactured structures and offer the potential to guide processing–structure–property understanding of these materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43671.     

炭黑/黏土/丁苯橡胶纳米复合材料的性能

研究了用1份(质量,下同)或2份黏土替代5份或10份炭黑对炭黑/黏土/丁苯橡胶纳米复合材料性能的影响。结果表明,用少量黏土非等量替代炭黑后,复合材料的物理机械性能变化不大;复合材料的耐磨性能随炭黑用量的减少而降低,耐屈挠疲劳性能随黏土用量增加而提高。当炭黑与黏土的填充量分别为45份和2份时,复合材料的物理机械性能和动态生热与填充50份炭黑时相当。     

炭黑填充橡胶复合材料动态力学性能和生热预报

基于应变放大因子的概念,对炭黑填充橡胶的动态力学性能和在不同外载条件下的生热性能作了分析预报。对非均一橡胶复合部件或混炼不充分导致炭黑分散不均匀胶料的生热性能和动态模量进行了研究。用两种材料并联而成的复合材料模型说明了炭黑分散度对橡胶性能的影响。结果表明,随着炭黑分散度的提高,动态模量和滞后损失都下降,并且趋于炭黑完全分散时的值。还对复合部件在不同我上的生热情况和动态性能作了比较。     

High‐density polyethylene/carbon black conductive composites. I. Effect of CB surface modification on its resistivity–temperature behavior

The effect of the interaction between a polymeric matrix and conductive particles of carbon black (CB), especially the interaction enhanced by oxidizing CB (o‐CB), on the resistivity–temperature behavior of its composites was studied. The results reveal that the interaction between ethylene‐vinyl‐acetate and CB is stronger than that between high‐density polyethylene and CB. The room temperature resistivity of the o‐CB filled system subsequent to thermal cycles increases to a lower extent in comparison with those filled with virgin CB. Moreover, the resistivity decrease of composites filled with o‐CB needs a longer time than that of the virgin CB filled system during isothermal annealing, meaning that the resistivity–temperature behavior of the former is much more stable than that of the latter. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3112–3116, 2002; DOI 10.1002/app.10049