含磷钛酸酯偶联剂改性膨胀型阻燃剂及其阻燃聚丙烯的研究

采用含磷钛酸酯偶联(剂PTCA)对由三聚氰胺焦磷酸(盐MPP)和季戊四(醇PER)复配组成的膨胀型阻燃(剂IFR)进行表面改性,并用其制备阻燃聚丙烯(PP)。研究了PTCA用量对PP/IFR共混物力学性能和阻燃性能的影响,并通过热重分析和扫描电镜对共混物进行了表征。结果表明:PTCA有效改善了IFR与PP基体的相容性,提高了PP/IFR共混物的力学性能及阻燃性能。当PTCA用量为1.0%时,共混物的拉伸强度和缺口冲击强度为27.3 MPa和3.2 kJ/m2,分别比未改性的PP/IFR提高了18.7%和6.7%;LOI从未改性PP/IFR的28.5%提高到31.5%,且通过UL94 V-0级;此外,共混物的热稳定性也明显提高,700℃时的残炭率由未改性PP/IFR的8.2%提高到12.1%。     

IFR/可膨胀石墨及协效剂氧化锌对PP阻燃性能影响的研究

制备了聚丙烯(PP)/有机膨胀型阻燃体系(IFR)、PP/IFR/可膨胀石墨(EG)和PP/IFR/可膨胀石墨(EG)/协效剂氧化锌(ZnO)三种体系,通过力学性能、氧指数(LOI)、垂直燃烧测试及热重分析(TG),探讨了复配膨胀型阻燃体系IFR/EG与协效阻燃剂ZnO之间的协同效应。结果表明,当IFR/EG/ZnO质量比为9.25/9.25/1.5时,阻燃PP的LOI值达到最高,同时阻燃PP的力学性能比不含ZnO的PP有所提高。TG结果表明,ZnO的加入使阻燃PP的热稳定性得到提高,形成了更稳定的保护层,从而提高了PP的阻燃效果。     

膨胀型阻燃剂和有机蒙脱土协同阻燃聚丙烯的研究

采用熔融插层法制备了聚丙烯/膨胀型阻燃剂/有机蒙脱土（PP/IFR/OMMT）阻燃复合材料。探讨了OMMT对PP膨胀阻燃体系的影响,通过X射线衍射(XRD)、极限氧指数、热重分析(TG)、力学性能测试对阻燃复合材料的阻燃性、热稳定性及力学性能进行了研究。结果表明,PP高分子链插层进入OMMT层间,形成了插层型复合材料。OMMT与IFR具有明显的协同阻燃性。OMMT添加量为2份时,复合材料的极限氧指数达到31 %,较单独添加IFR时高出30 %;与纯PP相比,复合材料残炭率明显提高。随着OMMT含量的增加,复合材料的拉伸强度、弯曲强度和冲击强度均呈现先上升后下降的趋势,当OMMT含量为3份、IFR含量为22份时,复合材料的拉伸强度、弯曲强度和冲击强度达到最大值。     

超疏水三嗪系膨胀阻燃剂的制备及其应用

采用硅树脂对三嗪系膨胀阻燃剂(IFR)进行表面包覆改性,并通过静态接触角测试对其进行了润湿性能表征。然后将改性前后的IFR分别添加到聚丙烯(PP)中制备了阻燃PP材料,并测试研究了该材料的阻燃性能、力学性能及耐水性。结果表明:当硅树脂的包覆量为5%时,改性IFR的接触角由改性前的0°上升到了151.3°,表现出超疏水性能。与未改性IFR阻燃的PP材料相比,由改性IFR得到的阻燃PP材料,其阻燃性能略有降低,但阻燃剂与聚合物的相容性以及阻燃PP的力学性能有所改善;同时阻燃PP的耐水性能显著提高,其阻燃剂的水抽出率大大降低。当阻燃剂添加量为20%时,未改性IFR阻燃的PP材料,其阻燃剂抽出率为3.71%,且耐水性测试后材料的阻燃性能明显下降;而改性IFR阻燃的PP材料,其阻燃剂抽出率仅为0.38%,且耐水性测试后材料的阻燃性能基本保持不变,表现出优良的耐水性能。     

不同膨胀型阻燃剂改性聚丙烯/聚乳酸复合材料

用两种不同的膨胀型氮磷阻燃剂(IFR1和IFR2)阻燃改性聚丙烯(PP)/聚乳酸(PLA)复合材料。结果表明:两种阻燃剂在PP/PLA基体中都具有良好的分散性和界面粘合性。阻燃剂的加入降低了材料的力学性能,而含有25%阻燃剂的PP/PLA复合材料就能到达垂直燃烧试验(UL-94)的V0等级。燃烧过程中阻燃剂通过在材料表面形成致密的炭层来提高材料的阻燃性,其中IFR1对PP/PLA体系的阻燃改性效果更好。从力学性能和阻燃效果的双重考虑,质量含量25%的阻燃剂适合于PP/PLA材料的阻燃改性。     

层状阻燃结构对PBT/IFR复合材料性能的影响

通过熔融共混和模压成型技术制备了聚对苯二甲酸丁二酯(PBT)/膨胀型阻燃剂(IFR)共混和层状复合材料,其中层状复合材料为3层阻燃结构,内层为非阻燃层(纯PBT),内层外面两层为阻燃层(PBT/IFR)。通过UL94垂直燃烧、极限氧指数(LOI)以及拉伸和冲击性能测试对比分析了两种复合材料的阻燃性能和力学性能。结果表明,与PBT/IFR共混复合材料相比,PBT/IFR层状复合材料的阻燃性能提高幅度更大,虽然低IFR含量下其力学性能低于共混复合材料,但随着IFR含量增加,力学性能下降幅度更小。当层状复合材料中的阻燃层/非阻燃层/阻燃层的厚度比为1.5 mm/1 mm/1.5 mm,即IFR质量分数为22.5%时,其拉伸强度、断裂伸长率和冲击强度与相同IFR用量下的共混复合材料相当,而阻燃性能与IFR质量分数为30%的共混复合材料相当,其UL 94阻燃等级达到V–0级,LOI提高到24.4%。这表明,采用层状阻燃可控受限结构,可在较低的IFR用量下更好地提高PBT/IFR复合材料的阻燃性能,同时减缓了力学性能下降的幅度。     

芳基磷酸酯/膨胀型阻燃剂协同阻燃PP的制备及性能研究

以间苯二酚双(二苯基)磷酸酯(RDP)为阻燃协效剂,与三聚氰胺焦磷酸盐(MPP)和季戊四醇(PER)组成的膨胀型阻燃剂(IFR)复配,制备了具有良好阻燃性能的无卤阻燃聚丙烯(PP)。研究了RDP的用量对PP/IFR体系阻燃性能和力学性能的影响,并通过热重分析(TGA)和动态热机械分析(DMA)等手段对阻燃材料进行了表征。结果表明:RDP与IFR具有明显的协同阻燃作用。当RDP质量分数为5.0%时,阻燃PP的氧指数(LOI)从28.5%提高至30.5%,UL-94由V-1级提升至V-0级;此外,体系的缺口冲击强度也有较大幅度提高。     

ZnB对LGFPP/IFR阻燃体系性能的影响

通过熔融共混法制备了长玻纤增强聚丙烯/膨胀阻燃剂/硼酸锌(LGFPP/IFR/ZnB)复合材料,并测定了其阻燃性、热稳定性及力学性能;通过扫描电镜(SEM)观察燃烧后的微观形貌,考察了ZnB对LGFPP/IFR阻燃体系性能的影响。结果表明:适当用量的ZnB与IFR阻燃剂具有协同阻燃作用,可提高LGFPP/IFR体系的阻燃性、热稳定性及力学性能。在LGFPP/IFR阻燃体系中添加2%的ZnB,LGFPP/IFR/ZnB复合材料的氧指数提高到23.6%;拉伸强度、弯曲强度和冲击强度分别提高了10.7%、15.1%和31.9%。     

三嗪阻燃剂阻燃聚丙烯性能研究

研究了两种三嗪系列阻燃剂IFR1和IFR2对聚丙烯(PP)阻燃性能的影响。进行了烟密度和力学性能测试,并利用差示扫描量热仪、热重分析仪、锥形量热仪和体视显微镜对阻燃PP的各项性能进行了进一步的表征。结果表明,随着IFR1和IFR2用量的增大,材料的拉伸强度先减小后增大,冲击强度减小,而且IFR2对材料上述性能的影响更小;IFR2能使PP的结晶温度和熔融温度提高;当IFR2用量为30 phr或IFR1用量35 phr时,材料均能达到UL94 V-0级(3.2 mm);随着IFR2用量的增大,PP/IFR2的分解温度和残余物含量逐渐降低;IFR2能够降低PP的热释放速率和生烟速率;从综合性能上看,IFR2的阻燃效果优于IFR1。     

EPDM/PP/IFR/Nano-ZnO阻燃复合材料的制备及其性能研究

将纳米氧化锌(nano-ZnO)作为协效改性剂与膨胀阻燃剂(IFR)复配,制成IFR/nano-ZnO复合阻燃剂,并将其用于三元乙丙橡胶/聚丙烯(EPDM/PP)复合材料的阻燃。研究了nano-ZnO用量对该EPDM/PP/IFR/nano-ZnO阻燃复合材料的阻燃性能和力学性能的影响。结果表明:EPDM/PP/IFR/nano-ZnO阻燃复合材料具有优良的阻燃性能,且材料的力学性能明显改善;另外,当nano-ZnO用量为2%时,该阻燃复合材料的综合性能最佳。     

Synergetic toughness and morphology of poly(propylene)/nylon 11/maleated ethylene‐propylene diene copolymer blends

Polypropylene (PP)/nylon 11/maleated ethylene‐propylene‐diene rubber (EPDM‐g‐MAH) ternary polymer blends were prepared via melt blending in a corotating twin‐screw extruder. The effect of nylon 11 and EPDM‐g‐MAH on the phase morphology and mechanical properties was investigated. Scanning electron microscopy observation revealed that there was apparent phase separation for PP/EPDM‐g‐MAH binary blends at the level of 10 wt % maleated elastomer. For the PP/nylon 11/EPDM‐g‐MAH ternary blends, the dispersed phase morphology of the maleated elastomer was hardly affected by the addition of nylon 11, whereas the reduced dispersed phase domains of nylon 11 were observed with the increasing maleated elastomer loading. Furthermore, a core‐shell structure, in which nylon 11 as a rigid core was surrounded by a soft EPDM‐g‐MAH shell, was formed in the case of 10 wt % nylon 11 and higher EPDM‐g‐MAH concentration. In general, the results of mechanical property measurement showed that the ternary blends exhibited inferior tensile strength in comparison with the PP matrix, but superior toughness. Especially low‐temperature impact strength was obtained. The toughening mechanism was discussed with reference to the phase morphology. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

钛酸酯偶联剂在膨胀型阻燃聚丙烯中的偶联作用

研究了钛酸酯偶联剂（TTOPP）对聚丙烯/膨胀型阻燃剂（PP/IFR）复合材料阻燃性能和力学性能的影响,并采用扫描电子显微镜、偏光显微镜和X射线衍射研究了复合材料的微观形态和结晶行为。结果表明,加入TTOPP后,IFR在PP中的分散更加均匀,PP球晶的大小趋于一致,适量的TTOPP改善了IFR与PP间的相容性,促进了IFR对PP形成β晶的诱导作用。当PP/IFR/TTOPP为75/25/0.375时,复合材料的综合性能最佳,自熄时间降到24 s,拉伸强度和冲击强度比PP/IFR分别提高了14.0 %和12.0 %。     

SIS/SBS/PP共混改性的研究

研究了新型聚丙烯(PP)合金材料的配方、制备、工艺及性能。分别讨论了不同用量的三元乙丙橡胶 (EPDM)、苯乙烯与异戊二烯嵌段共聚物(SIS)及苯乙烯与丁二烯嵌段共聚物(SBS)与PP组成的二元和三元共混体系对材料力学性能的影响。结果表明:SIS为PP较好的增韧剂,PP／SIS/SBS三元共混体系具有较好的协同效应,在某种程度上可以代替EPDM改性PP,共混改性后拉伸强度、扯断伸长率等性能优良。     

Dynamically cured polypropylene/Novolac blends compatibilized with maleic anhydride‐g‐polypropylene

In this article, the dynamic vulcanization process was applied to polypropylene (PP)/Novolac blends compatibilized with maleic anhydride‐grafted PP (MAH‐g‐PP). The influences of dynamic cure, content of MAH‐g‐PP, Novolac, and curing agent on mechanical properties of the PP/Novolac blends were investigated. The results showed that the dynamically cured PP/MAH‐g‐PP/Novolac blend had the best mechanical properties among all PP/Novolac blends. The dynamic cure of Novolac improved the modulus and stiffness of the PP/Novolac blends. The addition of MAH‐g‐PP into dynamically cured PP/Novolac blend further enhanced the mechanical properties. With increasing Novolac content, tensile strength, flexural modulus, and flexural strength increased significantly, while the elongation at break dramatically deceased. Those blends with hexamethylenetetramine (HMTA) as a curing agent had good mechanical properties at HMTA content of 10 wt %. Scanning electron microscopy (SEM) analysis showed that dynamically cured PP/MAH‐g‐PP/Novolac blends had finer domains than the PP/MAH‐g‐PP/Novolac blends. Thermogravimetric analysis (TGA) results indicated that the incorporation of Novolac into PP could improve the thermal stability of PP. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

The Effect of Vibration on Mechanical Properties of Blends of EPDM/PP in a Tri-screw Dynamic Mixing Extruder

The effects of vibration force field on mechanical properties of blends of EPDM/PP during process of plastics in tri-screw dynamic mixing extruders were investigated experimentally. It was found that vibration force field enhanced mechanical properties of blends of EPDM/PP, and the amplitude of enhancement varied as EPDM content varying. The yangs modulus, the impact strength and the tensile strength were improved the maximum 17, 28, and 17.3%, respectively under dynamic conditions than that under steady conditions. Mechanical properties of blends of EPDM/PP represented a tendency of a rising followed by a fall with the increase of vibration frequency and amplitude.     

Properties of Paper Sludge Filled Polypropylene (PP)/Ethylene Propylene Diene Terpolymer (EPDM) Composites: The Effect of Silane-Based Coupling Agent

Paper sludge was used as a filler in PP/EPDM composites and 3-aminopropyl triethoxysilane (3-APE) was used in this study as a coupling agent. The effects of filler loading and 3-APE on the mechanical properties, water absorption, morphology, and thermal properties of the composites were investigated. It was found that incorporation of a silane coupling agent (3-APE) increased the stabilization (equilibrium) torque, tensile strength, and Young's modulus but decreased the elongation at break and water absorption. Scanning electron microscopy (SEM) study of the tensile fracture surface of the composites indicated that the presence of 3-APE increased the interfacial interaction between paper sludge and PP/EPDM matrix. The addition of a silane coupling agent also increased the crystallinity of PP and thermal stability of PP/EPDM/PS composites.     

Polypropylene–intumescent flame‐retardant composites based on meleated polypropylene as a coupling agent

The phosphoric acid‐pentaerythritol‐melamine copolymer, which is composed of three main components of intumescent flame retardant (IFR) and has optimal intumescent degree, was selected as IFR. The influence of meleated polypropylene (PP‐g‐MAH) on the properties and compatibility of IFR polypropylene (PP) composites were studied. The results obtained from mechanical tests, rheological behavior of composites, and scanning electron microscope showed that PP‐g‐MAH was a true coupling agent for IFR/PP blends and did not change the necessary flame retardancy. The cocrystallization between bulk PP and PP segments of PP‐g‐MAH was also proven by WAXD analysis. Flow test showed that the flow behaviors of composites in the melt are those of a pseudoplastic and it is very small for PP‐g‐MAH affecting rheological behavior of the PP/IFR composite. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 257–262, 2002     

EPDM/聚烯烃共混型热塑性弹性体的研究

制备ＥＰＤＭ／聚烯烃简单共混型热塑性弹性体。研究了聚合物种类、橡塑比、二元和三元共混对共混物力学性能的影响。结果表明，部分结晶性ＥＰＤＭ共混物的力学性能比无定形ＥＰＤＭ共混物好，部分结晶性ＥＰＤＭ与ＬＤＰＥ（低密度聚乙烯）共混物的拉伸强度大于两者的加和值，而其它二元共混物的拉伸强度均低于两共混单元的加和值；用ＬＤＰＥ部分替代ＰＰ，或用氯磺化聚乙烯（ＣＳＭ）部分替代结晶性ＥＰＤＭ进行三元共混，能改善部分结晶性ＥＰＤＭ／ＰＰ共混物的某些性能。     

Mechanical properties,morphological structure,and thermal behavior of dynamically photocrosslinked PP/EPDM blends

A dynamically photocrosslinked polypropylene (PP)/ethylene–propylene–diene (EPDM) rubber thermoplastic elastomer was prepared by simultaneously exposing the elastomer to UV light while melt‐mixing in the presence of a photoinitiator as well as a crosslinking agent. The effects of dynamic photocrosslinking and blend composition on the mechanical properties, morphological structure, and thermal behavior of PP/EPDM blends were investigated. The results showed that after photocrosslinking, tensile strength, modulus of elasticity, and elongation at break were improved greatly. Moreover, the notched Izod impact strength was obviously enhanced compared with corresponding uncrosslinked blend. Scanning electron microscopy (SEM) morphological analysis showed that for uncrosslinked PP/EPDM blends, the cavitation of EPDM particles was the main toughening mechanism; whereas for dynamically photocrosslinked blends, shear yielding of matrix became the main energy absorption mechanism. The DSC curves showed that for each dynamically photocrosslinked PP/EPDM blend, there was a new smaller melting peak at about 152°C together with a main melting peak at about 166°C. Dynamic mechanical thermal analysis (DMTA) indicated that the compatibility between EPDM and PP was improved by dynamic photocrosslinking. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3371–3380, 2004