适用于3D打印技术的ABS/SEBS复合材料制备

采用热塑性弹性体苯乙烯–乙烯–丁烯–苯乙烯嵌段共聚物(SEBS)对丙烯腈–丁二烯–苯乙烯塑料(ABS)进行改性,制备3D打印ABS/SEBS复合材料,研究了SEBS的用量对3D打印ABS/SEBS复合材料流动性能、力学性能与热降解行为的影响。结果表明,随SEBS用量的增加,ABS/SEBS复合材料的熔体流动速率先增加后降低;随SEBS用量增加,ABS/SEBS复合材料的冲击强度增加,SEBS能提高ABS/SEBS复合材料的断裂伸长率,但同时也使拉伸强度和弯曲强度降低;随SEBS用量的增加,ABS/SEBS复合材料的热稳定性增加;当SEBS质量分数为15%时,ABS/SEBS复合材料在3D打印中的综合性能最好。     

不同化学结构的PP对热塑性弹性体复合材料性能的影响

研究了不同化学结构的聚丙烯(PP)对苯乙烯-乙烯/丁烯-苯乙烯共聚物(SEBS)/白油/PP热塑性弹性体复合材料力学性能和流动性能的影响。结果表明,复合材料的力学性能与所添加PP的力学性能保持一致,按照均聚PP、无规共聚PP、共聚PP的化学结构特性,复合材料的拉伸性能、弯曲性能和硬度都依次变小;但是复合材料的流动性能不仅和PP的熔体质量流动速率(MFR)有关系,而且还与PP和SEBS的相互作用有关。在PP的MFR相同的情况下,复合材料的MFR按照均聚PP、无规共聚PP、共聚PP的不同依次降低。     

充油SEBS/PP热塑性弹性体的制备及性能研究

采用HAAKE转矩流变仪制备了充油苯乙烯-乙烯-丁二烯-苯乙烯嵌段共聚物/聚丙烯(SEBS/PP)热塑性弹性体,利用热重分析(TG)、差示扫描量热法(DSC)等研究了填充油对SEBS/PP加工性能、热稳定性和力学性能的影响,并考察了该充油SEBS/PP中PP的结晶行为。结果表明:填充油的加入可以明显改善SEBS/PP的加工性能。在各种充油SEBS/PP体系中,添加了石蜡油KP6030的SEBS/PP体系具有最优综合力学性能,而且该体系的热分解温度最高、失重率最低、热稳定性能最好。另外在充油SEBS/PP体系中,PP的结晶温度降低、结晶度基本不变、结晶速率加快。     

无卤阻燃PP/SEBS复合材料的研究

采用高速混合机将聚丙烯(PP)、SEBS(苯乙烯-乙烯/丁烯-苯乙烯三嵌段聚合物),白油,含磷阻燃剂MPP(0,0-二甲基-0-[(4-甲巯基-3-甲基)-苯基]硫代磷苯酯)及协同剂等按照比例预混,经双螺杆挤出机挤出,制备无卤阻燃PP/SEBS热塑性弹性体材料。并采用聚氯乙烯(PVC)电线押出机制备单芯电线。燃烧测试结果发现:阻燃PP/SEBS材料的热释放速率(HRR)及热释放速率峰值(PHRR),总热释放量(THR)均明显降低,UL 94最高可以达V-0级,极限氧指数(LOI)达30%,材料的阻燃性显著提高。白炭黑(Si02)具有明显的阻燃协同作用。同时,对PP/SEBS阻燃材料及其制造的电线进行了测试,结果表明:制备的PP/SEBS阻燃电线阻燃性能达到VW-1级,强度≥10.0 MPa,热老化后的强度和断裂伸长率的保持率≥88%,其各项物性指标符合UL62/1581的要求,综合性能优异,是替代含卤PVC电线材料的良好选择。     

PTT/SEBS复合材料的制备及其流变性能

采用熔融共混法,将聚对苯二甲酸丙二酯（PTT）纤维与氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物（SEBS）弹性体共混制备PTT/SEBS复合材料,考察了SEBS弹性体含量对复合材料力学性能的影响,以及剪切速率、温度对复合材料流变性能的影响,并分析了复合材料的亚微相态。结果表明：加入SEBS弹性体使PTT/SEBS复合材料的拉伸强度提高,断裂拉伸应变降低;随着SEBS弹性体含量的增加,PTT/SEBS复合材料的流动阻力增大,流变性能降低。     

纳米有机蒙脱土改性SEBS/PP共混物的研究

通过熔融插层的方法将纳米有机蒙脱土（OMMT）与氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物（SEBS）／聚丙烯（PP）共混制备得到SEBS／PP／OMMT复合材料。X射线衍射实验证明,复合材料SEBS／PP／OMMT5％、SEBS／PP／OMMT10％片层间距分别为4．17nm,3．91nm,说明聚合物插层进入OMMT片层之间,制备得到SEBS／PP／OMMT插层复合材料。采用锥形量热仪测试材料的阻燃性能,燃烧测试结果表明,SEBS／PP／OMMT复合材料具有比较低的热释放速率和质量损失速率,并且随着OMMT添加量增加,复合材料的热释放速率、峰值热释放速率和总热释放先显著降低最后趋于一个稳定值。综合力学测试结果表明,当有机蒙脱土质量分数为5％～10％时,该复合材料的综合性能最好。     

PC/SEBS/CB抗静电复合物的加工方式研究

以聚碳酸酯（PC）／苯乙烯-乙烯／丁烯-苯乙烯共聚物（SEBS）共混物为基体材料,以导电炭黑（CB）为填料,通过熔融共混的方法制备了高抗冲抗静电复合材料。研究了PC／SEBS／CB一步挤出、分别以PC／CB和SEBS／CB为母粒两步挤出三种不同加工方式对复合物电性能和力学性能的影响。结果表明,采用母粒两步挤出的加工方式能够使PC／SEBS（质量比80／20）的发生渗滤转变时所需的炭黑质量分数从3．2％降低至2．1％;采用SEBS／CB母粒两步挤出时,添加质量分数20％的SEBS和质量分数3．5％的CB,能够获得电性能和力学性能俱佳的复合材料,缺口冲击强度达到63kJ／m^2,断裂伸长率保持在115％。     

PP-g-MAH对SEBS/PP/MH/EG阻燃复合体系结构与性能的影响

在氢氧化镁(MH)与可膨胀石墨(EG)复配阻燃石蜡油改性苯乙烯-乙烯/丁烯-苯乙烯(SEBS)/聚丙烯(PP)共混物(O-SEBS/PP)体系中,用马来酸酐接枝聚丙烯(PP-g-MAH)增容,研究其对O-SEBS/PP/MH/EG阻燃复合体系结构和性能的影响。结果表明:以一定量的PP-g-MAH代替基体中的PP增容后,复合材料在保持UL94垂直燃烧V-0级的同时,拉伸强度(σmax)与100%定伸强度(σ100)随着PP-g-MAH用量的增加而增大,在质量分数为6%时,分别为13.4 MPa和9.0 MPa,较未添加PP-g-MAH时分别提高13.6%和76.5%;撕裂强度则下降4.0%。复合材料的毛细管流变实验和淬断面扫描电子显微照片分析表明:PP-g-MAH的加入改善了复合材料中MH、EG与O-SEBS/PP共混物基体间的界面黏合力,提高了相容性。     

环氧大豆油对高流动苯乙烯-乙烯/丁烯-苯乙烯/聚丙烯复合材料的结构与流变性能的影响

以高流动苯乙烯-乙烯/丁烯-苯乙烯嵌段共聚物(SEBS)/聚丙烯(PP)复合材料体系为研究对象,进行红外、热重分析、流变性能等测试表征,系统研究了环氧大豆油(ESO)对SEBS/PP复合材料体系的结构、热稳定性、流变性能的影响,同时考察了ESO的加入对拉伸性能的影响。结果表明：加入ESO后,不会改变SEBS/PP的结构,使复合体系的柔韧性增加,加工性能变好,初始分解温度降低,但最大分解温度变化不大,随ESO含量增加,对复合材料热稳定性影响不大,对碳分解有促进作用,拉伸强度降低,ESO质量分数在5%以内,复合材料拉伸性能的保持率较好,均在78%以上,质量分数超过20%后性能会急剧下降。流变性能测试显示ESO的引入可以明显降低SEBS/PP复合体系的储能模量(G′)、损耗模量(G″)和负数黏度,未添加或是含量在5%以下,储能模量和损耗模量曲线图存在一个由黏性流体的特性向弹性固体的特性的转变点,添加10%及以上ESO,复合体系的G′相似文献   

SEBS和SEBS-g-MA对PPO/PP合金力学和流变性能影响

采用苯乙烯-乙烯-丁二烯-苯乙烯嵌段共聚物(SEBS)和马来酸酐接枝SEBS(SEBS-g-MA)增容改性聚苯醚/聚丙烯(PPO/PP)合金。通过正交试验综合考察了PP,SEBS/SEBS-g-MA含量对合金拉伸强度、冲击强度和弯曲强度的影响,优化了各组分之间的配比。结果表明,PPO/PP/SEBS-g-MA合金的综合力学强度较PPO/PP/SEBS合金高;当PPO/PP/SEBS质量比为48∶28∶24时,PPO/PP/SEBS(SEBS-g-MA)合金综合力学性能最佳;SEBS-g-MA和SEBS可降低PPO/PP合金的黏度,提高其加工性能。     

Structure and properties of polypropylene composites filled with magnesium hydroxide

Silane and silicone oil modified superfine magnesium hydroxide (MH) was filled into polypropylene (PP) as a flame retardant. The PP and flame‐retarded PP composites were studied for their mechanical properties and rheological behaviors by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), limiting oxygen index (LOI), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results showed that the addition of MH improved flame retardancy of PP/MH composites, but seriously deteriorated mechanical properties of the composites. Surface treatment of MH could significantly improve tensile and impact strength of PP/MH composite because of its enhanced interfacial adhesion between MH and PP matrix. DSC results showed that MH had heterogeneous nucleation effect on PP. Surface treatment of MH weakened its heterogeneous nucleation effect. POM results showed that the dispersion of MH particles played an important role in the crystalline morphology and spherulite size of PP crystals. TGA indicated that MH greatly enhanced the thermal stability of PP. The introduction of treatment agent further improved the thermal oxidative stability of the composite. According to LOI, silane‐treated MH greatly enhanced flame retardancy of PP/MH composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4943–4951, 2006     

Effects of zinc borate and microcapsulated red phosphorus on mechanical properties and flame retardancy of polypropylene/magnesium hydroxide composites

In this paper, the mechanical properties and flame retardancy of zinc borate (ZB) and microcapsulated red phosphorus (MRP) with modified magnesium hydroxide (MH) in flame-retardant polypropylene (PP) were studied by mechanical properties test, UL-94 test, and thermogravimetric analysis (TGA). The crystallization behaviors of the composites were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). The addition of ZB could improve tensile strength and elongation at break of PP/MH composite. The MRP powders had a little effect on the mechanical properties of the PP composites. DSC results showed the addition of ZB and MRP weakened the heterogeneous nucleation effect of MH on PP. The addition of ZB and MRP had a great effect on the flammability of the PP/MH/EG composites. The thermal stability of PP/MH/ZB and PP/MH/ZB/MRP composites was better than that of PP/MH composite.     

Enhanced flame retardancy,smoke suppression,and acid resistance of polypropylene/magnesium hydroxide composite by expandable graphite and microencapsulated red phosphorus

Low flame retardant efficiency and poor acid resistance of filled polymer composites are two main drawbacks of magnesium hydroxide (MH) as a flame retardant (FR). To solve these problems, expandable graphite (EG) and microencapsulated red phosphorus (MRP) were introduced into polypropylene/magnesium hydroxide (PP/MH) composite by melt compounding. The obtained PP/MH/EG/MRP quadruple composite was studied regarding its fire behavior as well as acid resistance. Obvious flame retardant synergism among MH, EG, and MRP is found in PP, which diminishes the loading of FR from 63.0 to 37.5 wt% to obtain V-0 rating in UL-94 test and low smoke release. Compact intumescent char with high thermo-oxidative stability was generated on composite surface, which plays a vital role in flame retardancy. The removal of MH by acid erosion on PP/MH/EG/MRP composite surface does not affect production of intumescent char and fire behavior of this composite. The composite displays good fire retardancy, smoke inhibition, and acid resistivity concurrently. This article renders an easy and cheap route to overcome the main faults of MH.     

硅烷交联无卤阻燃PP/POE复合材料的制备和性能

采用双螺杆挤出机和单螺杆挤出机两步熔融共混的方法,制备了硅烷接枝交联聚丙烯(PP)/乙烯辛烯共聚物(POE)/氢氧化镁（MH）/氢氧化铝（ATH）复合材料,并研究了不同硅烷接枝PP/POE共混物的效率和硅烷交联阻燃PP/POE复合材料的力学、热延伸、热失重和阻燃等性能。结果表明,PP/POE/MH/ATH/硅烷偶联剂A-151质量比为50∶50∶（95~47.5）∶（0~47.5）∶3.0时,复合材料的热延伸变形率≤25 %,冷却后永久变形率≤4 %;阻燃剂用量一定时,硅烷交联PP/POE/MH/ATH的极限氧指数随ATH含量增加而小幅度提高;PP/POE/MH/ATH复合材料的热稳定性低于PP/POE/MH复合材料;PP/POE/MH、PP/POE/MH/ATH、PP/POE/ATH的生烟速率依次变大。     

Flame retardancy and water resistance of novel intumescent flame‐retardant oil‐filled styrene–ethylene–butadiene–styrene block copolymer/polypropylene composites

A novel halogen‐free flame‐retardant composite consisting of an intumescent flame retardant (IFR), oil‐filled styrene–ethylene–butadiene–styrene block copolymer (O‐SEBS), and polypropylene (PP) was studied. On the basis of UL‐94 ratings and limiting oxygen index (LOI) data, the IFRs consisted of a charring–foaming agent, ammonium polyphosphate, and SiO₂ showed very effective flame retardancy and good water resistance in the IFR O‐SEBS/PP composite. When the loading of IFR was only 28 wt %, the IFR–O‐SEBS/PP composite could still attain a UL‐94 V‐0 (1.6 mm) rating, and its LOI value remained at 29.8% after a water treatment at 70°C for 168 h. Thermogravimetric analysis data indicated that the IFR effectively enhanced the temperature of the main thermal degradation peak of the IFR–O‐SEBS/PP composites because of the formation of abundant char residue. The flammability parameters of the composites obtained from cone calorimetry testing demonstrated that water treatment almost did not affect the flammability behavior of the composite. The morphological structures of the char residue and fractured surfaces of the composites were not affected by the water treatment. This was attributed to a small quantity of IFR extracted from the composite. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39575.     

Interfacial modification of high impact polystyrene magnesium hydroxide composites effects on flame retardancy properties

High impact polystyrene (HIPS)/magnesium hydroxide (MH) composites were prepared by melt‐blending. Two kinds of interfacial modifiers were used in this research, maleinated poly[styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene] (SEBS‐g‐MA) triblock copolymer and PS. The effects of the use levels of SEBS‐g‐MA on the flame retardancy of HIPS/elastomer/MH based on unmodified and PS‐modified surface were investigated by TEM, FTIR, and combustion tests (horizontal burning test and cone calorimetry). The combustion results showed that comparing composites containing unmodified MH, the flame retarding properties of composites containing PS‐modified MH were obviously improved. The increased performance can be explained that the PS covered on the surface of MH could further improve dispersion of the filler in matrix. Furthermore, there existed a critical thickness of interfacial boundary for optimum flame‐retarding properties in both ternary composites based MH and PS‐modified MH. When the interfacial boundary relative thickness is less than 0.53, the introduction of SEBS‐g‐MA can improve the dispersion degree, leading the improvement of flame retardancy properties. However, with the increase of interfacial boundary thickness, the SEBS‐g‐MA coating around MH acted as a heat and mass transfer barrier, leading to the reduction of flame retardancy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

OMMT和EG/MH协同阻燃LLDPE的研究

采用氢氧化镁(MH)、膨胀石墨(EG)和有机蒙脱土(OMMT)为阻燃剂制备了无卤阻燃线性低密度聚乙烯(LLDPE),研究了OMMT对LLDPE/EG/MH阻燃性能和力学性能的影响。结果表明:少量OMMT的加入,可以有效改善LLDPE/EG/MH的力学性能、阻燃性能和热稳定性。当OMMT质量分数为3.0%时,LLDPE/EG/MH/OMMT的拉伸强度和冲击强度分别为1.4 MPa和26.5 kJ/m~2;极限氧指数为35.0%,符合UL-94 V-0级;其热释放速率峰值、平均热释放速度、生烟速率和总生烟量比LLDPE/EG/MH的低。     

白炭黑改性膨胀阻燃剂对PP/POE燃烧及力学性能的影响

采用白炭(黑SiO2)作为协效阻燃剂,与膨胀阻燃(剂IFR)复配阻燃聚丙烯/乙烯-辛烯共聚物(PP/POE)复合材料,观察其用量对复合体系燃烧及力学性能的影响。结果表明:当SiO2/IFR/PP/POE为1/9/3.3/20时,体系的阻燃效果较好,垂直燃烧实验达到了UL 94 V-0级,拉伸强度提高很大,冲击强度略微降低,体系的综合性能最佳。     

聚丙烯/低温可膨胀石墨阻燃复合材料的性能研究

采用低温可膨胀石墨(LTEG)作为阻燃剂,制备了聚丙烯基阻燃复合材料。研究了聚丙烯/LTEG阻燃复合材料的阻燃性能、热性能、剩炭结构和力学性能。研究发现,采用LTEG为阻燃剂的聚丙烯基阻燃复合材料具有优异的阻燃性能,LTEG质量分数为15%时,复合材料氧指数已达27%。聚丙烯/LTEG复合材料的热失重温度低,在燃烧过程中并没有形成理想致密的炭层。LTEG对聚丙烯具有增强作用,随着其用量的增加,复合材料的拉伸强度增加,断裂伸长率不断下降。