SBS纳米复合材料的制备研究现状

介绍目前国内外SBS纳米复合材料的研究现状，重点介绍用蒙脱土和白泥制备SBS纳米复合材料的原理和方法，包括蒙脱土和白泥的精制改性、蒙脱土与高聚物的复合方法、复合熔融插层法和溶液插层法蒙脱土／SBS纳米复合材料的制备以及改性白泥和改性纳米层状白泥／SBS纳米复合材料的制备。指出制备耐热聚合物纳米粒子对SBS进行填充改性或采用纳米复合技术在SBS中引入纳米无机相进行增强反应是SBS纳米复合材料的研究方向。     

SBS/蒙脱土复合材料的制备及其性能Ⅱ.复合材料的性能

分别采用大分子溶液插层法和大分子熔融插层法制备了苯乙烯-丁二烯-苯乙烯共聚物（SBS）／蒙脱土纳米复合材料．研究了材料的力学性能。纳米结构的形成对复合材料的性能产生显著影响,少量蒙脱士的引入可以明显改善SBS／蒙脱土复合材料的力学性能。无论溶液插层法制备的星型SBS／蒙脱土纳米复合材料,还是熔融插层法制备的线型SBS／蒙脱土纳米复合材料,其拉伸强度和断裂伸长率都同时增加。其中,溶液插层法制备的纳米复合材料的拉伸强度和断裂伸长率分别较纯SBS增加了75％和55％;熔融法制备的纳米复合材料的托伸强度和断裂伸长率分别较纯SBS增加了70％和18％。     

SBS/粘土纳米复合材料的制备和性能研究

通过溶液插层法制备了苯乙烯—丁二烯—苯乙烯聚合物(SBS)／粘土纳米复合材料，并用X射线衍射透射电子显微镜分析其纳米分散结构及形态。研究结果表明：所得复合材料为插层型纳米复合材料；与SBS相比，SBS／粘土纳米复合材料断裂拉伸强度和300％定伸强度显著提高，储能模量明显提高。     

SBS/蒙脱土复合材料的制备及其性能Ⅰ.复合材料的结构

分别采用大分子溶液插层法和大分子熔融插层法制备了苯乙烯-丁二烯-苯乙烯共聚物(SBS),蒙脱土纳米复合材料,采用X射线衍射和透射电子显微镜对材料的结构进行了表征。结果表明,无论是采用大分子溶液插层法还是大分子熔融插层法,都能得到SBS／蒙脱土纳米复合材料。对于溶液插层法,蒙脱土插层剂的种类、SBS牌号对插层效果都有影响：对于熔融插层法,SBS牌号对是否形成插层型纳米复合材料影响最大,淬火对熔融挤出后得到的纳米复合材料无益。星形结构的SBS适宜于采用溶液插层法、线形结构的SBS适宜于采用熔融插层法制备纳米复合材料。     

纳米CaCO_3高填充ABS复合材料的制备

分别采用苯乙烯-丁二烯-苯乙烯共聚物(SBS)和乙烯-乙酸乙烯共聚物(EVA)作增韧剂,利用熔融挤出法制备纳米CaCO_3高填充丙烯腈-丁二烯-苯乙烯三元共聚物(ABS)/CaCO_3复合材料,研究了纳米CaCO_3填充量和增韧剂种类对ABS/CaCO_3复合材料力学性能和熔体流动速率的影响。结果表明:SBS对ABS/CaCO_3复合材料的增韧效果优于EVA;当ABS用量为100.0 phr、纳米CaCO_3填充量为25.0 phr、SBS用量为5.0 phr时,可得到力学性能符合GB/T 10009—1988要求的ABS/CaCO_3复合材料;当SBS和EVA用量较低时,SBS更能明显提高ABS/CaCO_3复合材料的熔体流动速率。     

纳米CaCO_3-AES复合材料制备和性能研究

分别以氯化聚乙烯(CPE)和苯乙烯-丁二烯-苯乙烯共聚物(SBS)作为增韧剂,利用熔融共混挤出法制备了纳米CaCO_3填充丙烯腈-三元乙丙橡胶-苯乙烯接枝共聚物(AES)复合材料,研究了纳米CaCO_3填充量和增韧剂种类对纳米CaCO_3-AES复合材料力学性能和热氧老化性能的影响。结果表明,适量的纳米CaCO_3加入到AES树脂中,可以与AES基体充分吸附、键合,提高AES树脂的力学性能;以CPE和SBS作为CaCO_3-AES复合材料增韧剂,添加质量分数12%的纳米CaCO_3的CaCO_3-AES复合材料,分别用质量分数12%的CPE、SBS改性复合材料,与未改性AES树脂相比,其拉伸强度相当,弯曲强度提高了10%,抗冲强度提高了20%;CPE增韧CaCO_3-AES的抗老化性能明显优于同比例的SBS增韧CaCO_3-AES。     

SBS和纳米SiO2协同增韧增强PP复合材料的研究

将热塑性弹性体苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)及纳米Si O2同时添加到聚丙烯(PP)中,以期在熔融共混过程中发挥SBS与纳米Si O2的协同增强增韧作用,达到有效改善PP综合性能的目的。用硬脂酸(SA)对纳米Si O2粒子表面进行功能化包覆改性,再经熔融共混技术制备了PP/SBS/纳米Si O2复合材料,研究了纳米Si O2表面处理效果及其用量对复合材料力学性能、流变性能及热性能的影响。力学性能研究结果表明,纳米Si O2与SBS对PP具有明显的协同增强增韧作用。当纳米Si O2质量分数为3.84%时,PP/SBS/纳米Si O2复合材料的综合性能最佳,其拉伸强度、断裂强度和拉伸弹性模量分别为37.4,23.8,129.9 MPa,室温(25℃)断裂强度比纯PP提高了100%;其室温和–20℃下缺口冲击强度分别较纯PP提高了51.5%和66.7%。微观形貌分析表明,熔融共混过程中,纳米Si O2均匀分散于PP基体中,复合材料基体在室温冲击下发生明显塑性变形,导致其冲击韧性明显高于低温冲击韧性。与纯PP相比,PP/SBS/纳米Si O2复合材料的流动性增大,耐热变形性能提高。     

纳米复合粒子GO-g-PS改性SBS复合材料性能的研究

通过原位自由基聚合法在氧化石墨烯(GO)表面接枝聚苯乙烯(PS),制备纳米复合粒子GO-g-PS,并以此对苯乙烯-丁二烯-苯乙烯三嵌段共聚物(SBS)进行改性,研究其对SBS物理性能、热稳定性和动态力学性能的影响。结果表明:PS成功接枝到GO表面,生成GO-g-PS;当GO-g-PS质量分数为0.03时,GO-g-PS改性SBS复合材料的拉伸强度和拉断伸长率较高;与SBS和GO改性SBS复合材料相比,GO-g-PS改性SBS复合材料的物理性能、热稳定性和高温峰玻璃化温度均提高。     

原位自由基聚合法在GO表面接枝PS及其对SBS的改性

以天然石墨为原料,采用改进的Hummers氧化法制备氧化石墨烯(GO),再通过原位自由基聚合法在GO表面接枝聚苯乙烯(PS),制备的产物即为纳米GO-g-PS复合粒子,并以此对苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)进行改性。采用傅里叶红外光谱(FTIR)、透射电镜(TEM)、热重分析(TGA)和拉伸试验对复合材料的结构和性能进行了表征。结果表明：SBS/GO-g-PS复合材料的力学性能、热稳定性都明显高于纯的SBS和SBS/GO复合材料。动态力学分析( DMA) 测试结果表明,SBS/GO-g-PS复合材料高温区的玻璃化转变温度比纯SBS和SBS/GO复合材料提高4℃。     

2005年中国聚丙烯研发与应用论文题录(上半年)

等通道转角挤出制备自增强等规聚丙烯的结构与性能研究,聚丙烯发泡体系粘度预测模型的确立,PP／POE／纳米CaCO3复合材料流变性能的研究,PP／SBS／纳米CaCO3复合材料结构与性能研究,聚丙烯基杂化材料的动态力学性能与流变行为.     

SBS/蒙脱土纳米复合材料耐热性能研究

采用溶液混合方法制备了苯乙烯/丁二烯三元嵌段共聚物（SBS）/有机蒙脱土（OMMT）纳米复合材料（NC）,对SBS/OMMT NC的热学性能进行了研究。结果表明,添加OMMT对于所有复合体系均提高了耐热性能,其中以SBS4402/OMMT-DK1B体系最为明显,热失重中心温度Tdc提高幅度达27℃;当OMMT用量为2.5质量份时,NC的Tdc最高,表明耐热性能最好,超过2.5质量份后,耐热性能下降;星型结构SBS耐热性能的提高明显高于线型SBS。     

Preparation and structure and mechanical properties of poly(styrene‐b‐butadiene)/clay nanocomposites

Star‐shaped and linear block thermoplastic poly(styrene‐b‐butadiene) copolymer (SBS)/organophilic montmorillonite clays (OMMT) were prepared by a solution approach. The intercalation spacing in the nanocomposites and the degree of dispersion of nanocomposites were investigated by X‐ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. The mechanical properties, dynamic mechanical properties, and thermal stability of these nanocomposites were determined. Results showed that SBS chains were well intercalated into the clay galleries and an intercalated nanocomposite was obtained. The mechanical strength of nanocomposites with the star‐shaped SBS/OMMT were significantly increased. The addition of OMMT also gave an increase of the elongation, the dynamic storage modulus, the dynamic loss modulus, and the thermal stability of nanocomposites. The increase of the elongation of nanocomposites indicates that SBS has retained good elasticity. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3430–3434, 2004     

Microstructure and rheological behavior of block copolymer/clay nanocomposites

Organic/Inorganic hybrid nanocomposites based on poly(styrene-butadiene-styrene) copolymer (SBS) and clay are fabricated by melt intercalation. The degree of intercalation is dependent on the surface properties of clay and SBS. The epoxized block in epoxized SBS acts as a strong attractive site with the clay surface, which yields the increased interlayer space in the layered silicates. It is also shown that the thermal stability of clay as well as the surface properties is very important in fabricating the polymer/clay nanocomposites. The rheological behavior of the SBS/clay nanocomposites is quite different from that of SBS itself. Both storage moduli and complex viscosity of the SBS/layered silicate nanocomposites increase and show non-terminal flow behavior.     

Structural and ordering behavior of lamellar polystyrene‐block‐polybutadiene‐block‐polystyrene triblock copolymer containing layered silicates

Nanocomposites based on organically modified montmorillonites (OMMTs) and sodium montmorillonite (CLO‐Na⁺) with poly(styrene‐b‐butadiene‐b‐styrene) (SBS) diblock copolymer have been investigated. Solution blending of OMMT suspension in toluene with SBS and subsequent static casting and annealing resulted in transparent films. Final samples were processed by compression molding. The intercalation spacing in the nanocomposites, microphase separation of the SBS, and the degree of dispersion of nanocomposites were investigated by X‐ray diffraction (Wide and small‐angle X‐ray scattering), transmission optical microscopy (TOM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The increase of basal spacing of OMMT in the nanocomposites suggested the intercalation of SBS. The lamellar structure perfection was extensively affected by both OMMT. AFM images and TOM micrographs only showed well dispersed but not exfoliated nanocomposites. On the other hand, TEM showed inserted tactoids into both blocks depending on the surfactant used (stained samples) and the dispersion of those tactoids (unstained samples). Fourier transform infrared spectroscopy indicated only the presence of the OMMT into the SBS. Deviations of the decomposition pathway of pristine SBS with addition of the OMMT were found by thermogravimetric analysis. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

SBS nanocomposites as toughening agent for polypropylene

The toughening of polypropylene [PP] with styrene–butadiene–styrene rubber [SBS]/montmorillonite [MMT] nanocomposites was investigated with respect to morphological, thermal, and mechanical properties. The MMT/SBS nanocomposites were prepared in an internal mixer, using an epoxidized SBS [SBSe] to investigate its effect as a compatibilizer. The MMT/SBS nanocomposite was added to PP up to 10 wt%, aiming at material toughening. Transmission electron microscopy (TEM) revealed MMT induced dispersed-phase reductions when compared to typical PP/SBS blends. In addition, changes in the PP crystallization process were observed in the presence of the nanocomposite. Surprisingly, the use of nanofiller, combined with SBSe compatibilizer agent, increased the PP impact strength by about 60%, with no reduction in the tensile module.     

Preparation and mechanical properties of clay/polystyrene‐block‐polybutadiene‐block‐polystyrene triblock copolymer (SBS) intercalated nanocomposites using organoclay containing stearic acid

Organoclays containing various amounts of stearic acid (SA) were synthesized, and clay/polystyrene‐block‐polybutadiene‐block‐polystyrene triblock copolymer (SBS) intercalated nanocomposites were prepared using organoclays containing SA by melt‐blending. Montmorillonite was the clay used, and both stearylamine and SA were used as surface modifiers. The amount of SA added was 0, 20, 50 and 100% of the cation‐exchange capacity (CEC). In this study, the effects of SA on the microstructure and mechanical properties of the clay/SBS nanocomposites were investigated. In clay/SBS with 100% CEC of SA, although no exfoliation of the clay occurred, the stacked clay layers were uniformly dispersed at the nanometer level (100–800 nm) without agglomeration. Clay/SBSs containing SA exhibited superior mechanical properties compared to clay/SBS without SA. It was found that SA effectively improved the clay dispersion in the SBS matrix and the mechanical properties of the clay/SBSs. Copyright © 2006 Society of Chemical Industry     

SBS／蒙脱土纳米复合材料的流变行为

用毛细管流变仪测定并研究了热塑性丁苯三嵌段共聚物（SBS）／蒙脱土纳米复合材料的熔体的稳态剪切流变行为，研究结果表明：温度和压力一定的条件下，加入一定量的改性蒙脱土可以降低熔体的粘度；在较低的剪切速率下，即出现剪切变稀现象；在高剪切速率下，粘度对剪切速率的敏感性是降低的，改性蒙脱土加入量对熔体的剪切粘度影响较小，主要是由基体材料所决定的；随温度的升高熔体粘度对剪切速率的敏感性是降低的。采用转矩流变仪对材料的加工性能进行研究，发现复合材料的加工性能基本上保持了纯SBS的加工性能。     

Preparation and characterization of poly(styrene‐b‐butadiene‐b‐styrene)/montmorillonite nanocomposites

With some polymerizable small molecules grafting onto the montmorillonite surface, we disposed the clay through in‐situ emulsion polymerization, and the structure of the modified montmorillonites were studied through Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD). The nanocomposites of poly(styrene‐b‐butadiene‐b‐styrene) (SBS)/montmorillonite with excellent mechanical properties were prepared by mixing SBS and the modified montmorillonite on the double rollers at 150°C. The exfoliation of the layered silicates was confirmed by XRD analysis and transmission electron microscopy (TEM) observation. After mechanical kneading of the molten nanocomposites, the exfoliation structure of the silicates is still stable for polystyrene macromolecules grafting onto the silicates. Upon the addition of the modified montmorillonite, the tensile strength, elongation at break and tear strength of the nanocomposites increased from 22.6 MPa to 31.1 MPa, from 608% to 948%, from 45.32 N/mm to 55.27 N/mm, respectively. The low‐temperature point of glass‐transition temperature (T_g) of the products was about −77°C, almost constant, but the high‐temperature point increased from 97°C to 106°C. In addition, the nanocomposites of SBS and modified montmorillonites showed good resistance to thermal oxidation and aging. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers