可生物降解聚(3-羟基丁酸酯-co-4-羟基丁酸酯）/层状?-磷酸锆纳米复合材料的制备及性能

以可生物降解聚（3-羟基丁酸酯-co-4-羟基丁酸酯）[P(3,4)HB]为基体,有机改性层状化合物?-磷酸锆（OZrP）为增强相,采用溶液插层法制备了P(3,4)HB/OZrP纳米复合材料。分别用X射线衍射仪（XRD）、扫描电镜（SEM）、偏光显微镜（POM）、热重分析仪（TGA）和差式扫描量热仪（DSC）等对其微观结构、热稳定性、结晶行为及降解性能进行了表征与分析。研究表明,具有纳米片层结构的OZrP能均匀分散在P(3,4)HB基体中形成纳米复合结构,OZrP能通过异相成核作用促进P(3,4)HB的结晶,并能促进P(3,4)HB的降解,但降低P(3,4)HB 的热稳定性。     

P(3,4HB)/PHBV共混改性及微生物降解研究

将聚(3羟基丁酸共聚4羟基丁酸酯)［P(3,4HB)］与聚(3羟基丁酸共聚3羟基戊酸酯)(PHBV)通过溶剂共混的方式进行共混改性,研究了改性后材料力学性能的变化情况,并进一步利用差示扫描量热法和热重法进行了表征,最后利用Pseudomonas mendocina DS04-T菌株对共混材料的降解性能进行了考查,并利用扫描电子显微镜观察了薄片降解后的微观形貌。结果表明,当P(3,4HB)与PHBV的混合比例为80/20时复合材料有较好的力学性能,断裂伸长率和拉伸强度均达到最大值;当PHBV组分的含量小于60 %时,共混物均形成了稳定的晶体结构,且两组分具有较强的相互作用和较好的相容性;Pseudomonas mendocina DS04-T对共混材料的完全降解时间大大低于单独降解P(3,4HB)所需的时间。     

聚(3-羟基丁酸酯-co-4-羟基丁酸酯)/纳米氮化钛共混体系研究

采用熔融共混方法制备了聚(3-羟基丁酸酯-co-4-羟基丁酸酯) [P(3HB-co-4HB)]和纳米氮化钛(TiN)的复合体系,并通过万能材料试验机、差示扫描量热仪(DSC)、偏光显微镜(POM)、X射线衍射仪(XRD),热失重分析仪(TG)等测试手段考察了不同含量TiN对P(3HB-co-4HB)基体的力学、热力学及结晶性能的影响.结果表明:纳米氮化钛在共混体系中起到成核剂作用,可有效改善P(3HB-co-4HB)结品性能,提高其韧性.     

聚(3-羟基丁酸酯-co-4-羟基丁酸酯)的性能

采用毛细管流变仪、差示扫描量热仪、热失重分析仪及偏光显微镜(POM)研究了聚(3-羟基丁酸酯-co-4-羟基丁酸酯)[P(3HB-co-4HB)]的流变性能、热性能及结晶性能.P(3HB-co-4HB)熔体属于典型的假塑性流体,剪切应力与剪切速率关系符合Ostwald-de Wale幂率定律,熔体表观黏度与温度的关系符合Arrhenius方程;P(3HB-co-4HB)的玻璃化转变温度约为-10℃,熔点在100～120℃,降解温度约为205℃;POM观察发现,P(3HB-co-4HB)在约78℃时球晶半径径向生长速率最大.     

聚(3-羟基丁酸酯-co-4-羟基丁酸酯)/酰胺成核剂共混体系

采用熔融共混方法制备了聚(3-羟基丁酸酯-co-4 -羟基丁酸酯)[P( 3HB-co-4HB)]和酰胺成核剂的复合体系,并通过万能材料试验机、差示扫描量热仪( DSC)、偏光显微镜(POM)和X射线衍射仪(XRD)等测试手段考察了不同含量酰胺成核剂对P( 3HB-co-4HB)基体的力学、热力学及结晶性能的影响.结果表明:酰胺成核剂在共混体系中起到成核剂作用,可有效改善P(3 HB-co-4HB)结晶性能,提高其韧性.     

聚乳酸/聚羟基脂肪酸酯共混物辐照交联

聚乳酸(PLA)/聚(3-羟基丁酸酯-co-4-羟基丁酸酯)[P(3HB-co-4HB)]共混后,通过电子束辐照在0~100 kGy的剂量范围内使之交联,然后测试凝胶含量、材料回缩性能、力学性能,并进行差示扫描量热分析。结果显示,辐照交联PLA/P(3HB-co-4HB)后,材料具有形状记忆功能,其屈服强度提高,断裂伸长率降低;辐照交联提高了PLA/P(3HB-co-4HB)耐热性,降低了材料结晶性能。     

膨胀型阻燃剂APP/MPR/PEPA的制备及其在ABS中的应用

用氧代-4-羟甲基-2,6,7-三氧杂-1-磷杂双环[2,2,2]辛烷(PEPA)作为成炭剂,用三聚氰胺酚醛树脂(MPR)作为气源和聚磷酸铵(APP)按一定比例复配成膨胀型阻燃剂(IFR),用于丙烯腈-丁二烯-苯乙烯共聚物(ABS)的阻燃研究。研究IFR的比例和含量对ABS燃烧性能的影响。阻燃实验结果表明,APP/MPR/PEPA质量比按2/1/2和3/3/4比例复配阻燃效果最佳,添加量为30%时,阻燃复合材料燃烧等级达到V-0,氧指数分别为29.4%和29%;热重分析和扫描电镜结果表明,阻燃复合材料热稳定性能较纯ABS有所降低,微观炭层更加致密无孔洞。     

P(3HB-co-4HB)/α-CSH复合材料的结晶性能和流变性能研究

采用共混的方法制备了聚(3-羟基丁酸酯-co-4-羟基丁酸酯)/α-半水硫酸钙晶须(P(3HB-co-4HB)/α-CSH)复合材料,研究了α-CSH用量对复合材料结晶性能和流变性能的影响。结果表明:α-CSH对P(3HB-co-4HB)具有明显的异相成核作用,提高了复合材料的熔融温度和结晶度。P(3HB-co-4HB)/α-CSH复合体系的表观黏度随着剪切速率的增加和温度的升高而逐渐降低,随着α-CSH用量的增加先减小后增大。复合材料的非牛顿指数(n)随着温度的升高而增大,随着α-CSH用量的增加先增大后减小,且n值均小于1,属于假塑性流体。复合材料的黏流活化能随着剪切速率的增加而逐渐减小,随着α-CSH用量的增加先减小后增大,但总体呈下降的趋势。     

聚3-羟基丁酸酯4-羟基丁酸酯性能研究

概述了聚羟基脂肪酸酯(PHA)类生物塑料的发展过程,分析了聚3-羟基丁酸酯4-羟基丁酸酯(P34HB)的结构、综合性能、加工特性,详细介绍了P34HB的改性方法。结果表明:P34HB是新一代优异的生物塑料,通过改性,其力学性能与聚丙烯和聚乙烯相近,可以在传统塑料加工设备上加工成型。但对P34HB的研发及应用还需做大量工作。     

聚乳酸/聚(3-羟基丁酸酯-co-4-羟基丁酸酯)/改性高岭土纳米复合材料的结晶、动态力学及流变行为

为提高聚乳酸(PLA)/聚(3-羟基丁酸酯-co-4-羟基丁酸酯)(P(3HB-co-4HB))基体的综合性能,采用熔融共混法制备聚乳酸/聚(3-羟基丁酸酯-co-4-羟基丁酸酯)/改性高岭土(modified kaolin)纳米复合材料。利用DSC、DMA、旋转流变仪、扫描电镜(SEM)等对复合体系的结晶、动态力学性能、流变行为、表面结构等进行了研究。结果表明:复合体系的冷结晶温度逐渐变小,降低了12.5℃,结晶能力有所提高。此外,结晶度由21.65%增加到35.22%,提高了62.68%。DMA结果显示,随着改性高岭土添加量的增多,复合体系的储能模量E′和玻璃化转变温度出现先增大后减小的变化。熔融态下,复合体系的黏度随剪切速率的增大而减小,属假塑性流体。当体系中改性高岭土添加量为4%时,材料的缺口冲击强度有明显的改善。利用SEM发现,少量改性高岭土可以均匀地分散在PLA/P(3HB-co-4HB)基体中并能显著提高复合体系的韧性。     

改性赤泥协同膨胀型阻燃剂阻燃聚乙烯

以聚磷酸铵（APP）、季戊四醇（PER）和三聚氰胺（MEL）复配的膨胀型阻燃体系（IFR）为主要阻燃剂,表面改性后的赤泥（Ti-MRM）作为协效剂阻燃聚乙烯（PE）,采用熔融共混法制备PE基阻燃复合材料（PE/IFR-Ti-MRM）。通过热重分析仪（TGA）、垂直燃烧仪（UL-94）、极限氧指数测定仪（LOI）及扫描电镜（SEM）等对其热氧稳定性、燃烧等级、阻燃性能和残炭形貌进行了表征与分析。结果表明：加入改性赤泥的PE/IFR-Ti-MRM复合材料形成的炭层更加致密和连续,当最优配比时,复合材料的极限氧指数达到32.2,燃烧等级达到V-0级;而PE/IFR阻燃复合材料的极限氧指数只能达到27.5,燃烧等级为V-2级。     

Preparation of aluminum diethyl hypophosphite intercalation-modified montmorillonite AlPi-MMT and its effect on the flame retardancy and smoke suppression of thermoplastic polyester elastomer

An aluminum diethyl hypophosphite intercalation-modified montmorillonite flame retardant (AlPi-MMT) is successfully prepared and characterized by FT-IR, SEM, and X-ray diffraction. It is found that thermoplastic polyester elastomer (TPEE) composites incorporating 15 wt% AlPi-MMT flame retardant exhibited better char formation and flame retardant properties compared to those incorporating 15 wt% (4:1, w:w) AlPi and MMT. And the char residual of TPEE/AlPi-MMT at 700°C is 16.17%, which is higher than that of TPEE/AlPi-MMT at 13.94%. and the former can pass UL-94 V-0 rating test while the latter can only pass UL-94 V-1 rating test. Afterwards, the combustion performance of TPEE composites is characterized, and it is found that the heat release and smoke release of TPEE/AlPi-MMT are greatly reduced compared with those of pure TPEE and TPEE/AlPi/MMT, which is a flame retardant and smoke suppressant TPEE composite. Finally, by analyzing the residual char morphology and elements of TPEE composites after combustion, the mechanism of the flame retardant AlPi-MMT to promote char formation and flame retardancy is demonstrated.     

新型含氮阻燃剂/PEPA协同阻燃PP的性能

以三聚氯氰、对羟基苯甲酸甲酯、水合肼为原料经两步反应合成了一种新型含氮阻燃剂4,4′,4″–(1,3,5–三嗪–2,4,6–三取代)三氧三苯甲酰肼(TNTN),并通过核磁共振等对其进行表征。将合成的含氮阻燃剂TNTN与1–氧–4–羟甲基–2,6,7–三氧杂–1–磷杂双环[2.2.2]辛烷(PEPA)以不同配比制备膨胀型阻燃聚丙烯(PP)材料(IFR–PP)。通过极限氧指数(LOI)、垂直燃烧(UL–94)、热重(TG)分析、锥形量热(CCT)法以及扫描电子显微镜(SEM)对阻燃PP燃烧及热稳定性能进行表征。结果表明,IFR–PP同时具有良好的阻燃性及抗熔滴能力,当PEPA∶TNTN=2∶1时,UL–94达到V–0级,LOI值达到了33.7%,表现出良好的阻燃性能。TG测试表明:阻燃剂的加入使IFR–PP材料提前降解,同时提高了材料的成炭性能,当PEPA∶TNTN=5∶1时,600℃时IFR–PP材料的残炭量由空白样的0.07%提高到了20.6%。CCT测试表明:相对于纯PP,经阻燃剂改性后的PP热释放率和总热释放量均显著减少。SEM测试表明:不同配比阻燃剂的加入使PP在燃烧过程中形成膨胀、致密的炭层,很好地保护了下层材料,提高了PP材料的阻燃性能。     

A novel bio-based charcoal-forming agent based on chitosan and phytate@Mg to improve the flame retardancy of poly(lactic acid)

A novel bio-based carbon forming agent (Mg@PA-CS) containing P and N elements was were synthesized using the complexation characteristics of chitosan (CS) and phytate (PA). The flame retardant behavior of poly(lactic acid) (PLA)/Mg@PA-CS/APP composites (addition of 20 wt% of different ratios of Mg@PA-CS and APP to polylactic acid composites) were investigated by the limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetry test (CCT), and thermogravimetric analysis (TGA). Due to the biphasic flame retardant and synergistic effect, since the 20 wt% flame retardant system (Mg@PA-CS:APP = 1:2), PLA composites passed the UL-94 test V-0 rating, reached 34% LOI value. The peak heat release rate (PHRR) and total heat release rate (THR) were reduced to 1/2 of the pure PLA, char residue could be as high as 11.49% at 800°C. Moreover, the flame-retardant mechanism of PLA composites during thermal decomposition was analyzed using a scanning electron microscope (SEM) and the coupling techniques of TGA linked with FT-IR (TG-FTIR).     

Vinyl polysiloxane microencapsulated ammonium polyphosphate and its application in flame retardant polypropylene

Vinyl polysiloxane microencapsulated ammonium polyphosphate (MAPP) was prepared by a sol-gel method using vinyltrimethoxysilane as a precursor to improve its thermal stability and hydrophobicity. The MAPP was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and thermogravimetric analyzer (TGA). The results showed that ammonium polyphosphate (APP) was successfully coated with vinyl polysiloxane. MAPP and pentaerythritol (PER) were used together to improve the flame retardancy of polypropylene (PP). The flame retardant properties of PP composites were investigated by limiting oxygen index (LOI), UL-94 test, TGA and SEM. When the MAPP was added as a flame retardant, with PER as a char forming agent, the LOI of PP/MAPP/PER composites was 33.1%, and it reached the UL-94 V-0 level. The results also demonstrated that the flame retardant properties of PP/MAPP/PER composites were better than those of PP/APP/PER composites at the same loading. Moreover, the addition of flame retardant and carbon forming agent could promote the crystallization behavior of PP.     

锡酸镁对膨胀阻燃聚丙烯的协效研究

在以聚乙烯基脲醛和聚磷酸铵构成的膨胀型阻燃剂阻燃聚丙烯的基础上,加入少量锡酸镁用作阻燃协效剂,并通过锥形量热仪、TG、FTIR、SEM及EDX 能谱分析等,研究了锡酸镁对该体系阻燃性能及炭层结构的影响。研究表明,添加1％锡酸镁能增加燃烧残余率,使炭层更连续致密,明显提高阻燃效率,有焰燃烧时间由415s增加到805s。与未添加锡酸镁相比,在达到UL-94 V-0（1.6mm）的阻燃级别时,阻燃剂的添加量由32％减少到28％,氧指数由33.4%提高到35.1%,阻燃材料的拉伸强度由24.3MPa提高到26.0MPa,断裂伸长率由23％增加到45％。     

磷腈/三嗪双基分子复配阻燃聚乳酸

将磷腈/三嗪双基分子阻燃剂（HTTCP）分别与六苯氧基环三磷腈（HPCTP）和季戊四醇磷酸酯（PEPA）按不同配比复配,采用熔融共混法制备了阻燃聚乳酸（PLA）的复合材料。采用热失重分析仪、极限氧指数仪、垂直燃烧试验箱和锥形量热仪研究了2种复配阻燃体系及其配比对PLA阻燃复合材料热稳定性和阻燃性能的影响,并采用扫描电子显微镜对材料的残炭形貌进行了分析,探究了其阻燃机理。结果表明,PEPA/HTTCP复配阻燃剂的阻燃效果优于HPCTP/HTTCP复配阻燃剂。当PEPA/HTTCP的质量比为3/1,总添加量为20 %时,阻燃PLA的极限氧指数最高,为27.2 %,热释放速率峰值、平均热释放速率以及热释放总量达到最小值,且能够达到UL 94 V-0级。     

含PEPA/纳米Al(OH)3的膨胀型阻燃聚丙烯研究

用磷酰基季戊四醇（PEPA）替代传统的季戊四醇作为炭源，与APP、三聚氰胺复合组成膨胀型阻燃剂（IFR），制备了膨胀型阻燃聚丙烯（IFR-PP）。讨论了阻燃剂对IFR-PP的阻燃性能、力学性能、热稳定性的影响，以反纳米Al（OH）3对该阻燃体系的影响。结果表明：PEPA在阻燃效果上优于季戊四醇，且PEPA对IFR-PP力学性能的影响小于季戊四醇，当PEPR用量为5份，纳米Al（OH）3用量为15份时，阻燃级别达UL-94 V-0级。同时，纳米Al（OH）3的添加使IFR-PP体系阻燃效果得到提高，且对材料的热稳定性反力学性能影响较小。     

Preparation,characterization and its flame retardance performance of microencapsulated ammonium polyphosphate/ bridged polysesquisiloxane polyurethane composites

A core shell material consisting of ammonium polyphosphate as core and 4,4-oxydianiline-formaldehyde resin as shell was prepared through a situ microencapsulation technology. The monomer of the polyurethane (PU) was modified to form bridged polysesquisiloxane. The purpose of modification is to improve the thermal stability of polyurethane matrix through the formation of networks. The degree of the networks was evaluated by solid state ²⁹Si-nuclear magnetic resonance. The structure and hydrophobic property of microencapsulated flame retardant were characterized using X-ray photoelectron spectroscopy and water solubility. The results indicated that the microencapsulation of APP with 4,4′-oxydianiline-formaldehyde resin (OF resin) resulted in improved hydrophobicity. The thermal properties of final flame retardant were systematically analyzed through thermogravimetric analysis. Limiting oxygen index and UL-94 test were used to classfied the flame retardant properties of varying the composition of APP and OFAPP in silanol-terminated polyurethane composites. Pure PU exhibited an LOI of 17 % and failed the UL-94 test. The LOI values of the 40 % OFAPP-added composites can reach 41 % and pass V-0 level. The results revealed that the microcapsulation of commercial flame retardant can improve the flame retardance of the composites.     

无卤膨胀型阻燃聚乙烯的性能研制

选择自制碳源、酸源、气源与一体的阻燃剂B-1,螺环类阻燃剂-PEPA及具有酸源和气源的多聚磷酸铵(APP)为基本阻燃元素进行配方设计,考察了不同成碳剂品种(A1、A2、A3、A4、A5)及用量对阻燃效果的影响。试验结果表明:PEPA与APP复配具有很好的阻燃效果,当PEPA/APP配比在60~40/40~60范围内,成碳剂A1加入量为1.0%,阻燃剂总添加量为30%时达到UL-94 V-0标准,通过优化偶联剂的品种和用量,使膨胀型阻燃聚乙烯在拥有阻燃效果的同时具有优良的力学性能及加工性能。