邻苯二甲酸二辛酯与PHB共混改性的研究

采用邻苯二甲酸二辛酯(DOP)对聚3-羟基丁酸酯(PHB)进行共混改性，并对共混物的流变行为、结晶行为和力学行为进行了研究。结果表明，DOP与PHB具有良好的相容性，能降低PHB的结晶行为，降低熔融温度，加宽熔融温区，改善加工条件，提高韧性。     

PHB及改性体系的热性能与流变性能

采用热差分析法分析了聚3-羟基丁酸酯( PHB)的热性能及邻苯二甲酸二辛酯(DOP)、滑石粉对其热性能的影响,研究PHB的流变性能以及DOP、滑石粉对PHB流变性能的影响.结果表明:PHB的黏度随剪切速率增大而迅速下降.DOP加入会显著降低其熔点,并对其剪切变稀现象改善较大.而滑石粉的加入使其流动性先减小后增大,对其剪切变稀稍有缓解作用.     

PHBV共混改性研究进展

介绍了聚(β-羟基丁酸戊酸酯)(PHBV)的现有生产状况、性能特点以及存在的不足。简述了PHBV结晶改性的研究成果,总结了PHBV共混改性的研究进展,包括PHBV与聚乳酸(PLA)、聚己内酯(PCL)、聚己二酸/对苯二甲酸丁二醇酯(PBAT)、二氧化碳共聚物(PPC)、淀粉、纤维素及有机黏土等。     

P34HB共混改性聚乳酸纤维柔软性能研究

将聚乳酸与聚3-羟基丁酸酯-4-羟基丁酸酯共聚物(P34HB)按一定比例进行共混,再用熔融纺丝的方法制备聚乳酸共混纤维,通过扫描电镜、X射线衍射仪、织物风格仪等对纤维的结晶取向、相容性、力学性能、手感等进行了研究。结果表明:随着P34HB含量增加,共混纤维的断裂强度下降,断裂伸长率变大,分子链的取向度、动态弹性模量降低;但P34HB的加入,能大大改善织物的表面粗糙度,特别在P34HB质量分数为40%的时候,共混织物表面粗糙度为3.07μm,表面光滑;并且该比例的织物易剪切变形,剪切回复力好,能轻松错动。     

PHB/PLLA/PEO共混纤维的晶态结构与拉伸性能研究

采用溶液干纺法制备了聚β-羟基丁酸酯/聚乳酸/聚氧乙烯(PHB/PLLA/PEO)共混纤维,研究了PHB/PLLA/PEO初生纤维的晶态结构、在50℃和110℃下拉伸后共混纤维的力学性能及表面形态。结果表明:PHB与PLLA在PHB/PLLA/PEO共混纤维中的晶型均为α晶型;初生纤维经50℃和110℃拉伸2倍后,纤维的断裂强度均有所增加,断裂伸长率减小,50℃拉伸的纤维断裂强度高于110℃拉伸,其断裂方式均为韧性断裂;w(PEO)为5%,PHB/PLLA质量比为1:1,50℃拉伸2倍的PHB/PLLA/PEO共混纤维断裂强度为0.471 cN/dtex,断裂伸长率为34.05%     

聚羟基丁酸己酸酯／聚乙二醇共混膜的制备与性能研究

采用溶液浇铸法制备了聚羟基丁酸己酸酯/聚乙二醇(PHBHHx/PEG)共混膜,用DSC和POM研究了其热性能与结晶行为,并测量了其静态水接触角.结果表明,PHBHHx与PEG间存在较强的相互作用.在第二次升温过程中,个别共混比例的PHBHHx在PEG的诱导下可以发生一定程度的结晶,PEG起成核剂的作用.当PEG质量分数为40%时,PHBHHx亲水性能有所改善.PEG的加入对PHBHHx的球晶形态有影响,一定量PEG的加入可以加快PHBH-Hx的结晶速度.     

PHB和PHBV注塑和挤出成型工艺研究

对聚3-羟基丁酸酯(PHB)和聚3-羟基丁酸3-羟基戊酸酯(PHBV)的热性能和流变性能进行了测试和比较。结果表明:两者的加工温度范围均较窄,剪切变稀严重;PHBV比PHB的熔融温度和分解温度稍低。以此为依据,通过注塑和挤出成型实验,分析了PHB和PHBV的加工特点,确定了其注塑和挤出成型工艺条件。     

PLA/P34HB共混纤维的制备与性能

采用熔融纺丝法制备了聚乳酸（PLA）/聚（3-羟基丁酸酯-co-4-羟基丁酸酯）（P34HB）共混纤维,分析了P34HB含量对PLA/P34HB共混纤维热学性能、结晶性能和力学性能的影响,并研究了拉伸倍数对P34HB含量为30%(w)的共混纤维性能的影响。结果表明：当拉伸倍数为3倍时,随着P34HB含量的增加,PLA/P34HB共混纤维的结晶度逐渐降低,断裂强度和初始模量逐渐下降,而断裂伸长率逐渐增大;随着拉伸倍数的增大,P34HB含量为30%(w)的PLA/P34HB共混纤维的结晶度、断裂强度和初始模量逐渐提高,断裂伸长率逐渐降低,当拉伸8倍时,共混纤维的断裂强度达到425 MPa,断裂伸长率为15.5%,初始模量为7 005 MPa。     

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。     

聚羟基丁酸酯共混改性的研究进展

阐述了近年来生物塑料聚卢．羟基丁酸酯(PHB)共混改性的研究进展;介绍了PHB生物合成、化学改性和物理共混3种改性手段;分别探讨了PHB与非生物降解聚合物、可生物降解聚合物之间的共混情况,特别就共混体系的相容性、玻璃化转变温度、结晶性及机械性能进行了总结和评述;并展望了PHB材料的改性方向。     

Thermal analyses of poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Thermal analyses of poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(HB–HV)], and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(HB–HHx)] were made with thermogravimetry and differential scanning calorimetry (DSC). In the thermal degradation of PHB, the onset of weight loss occurred at the temperature (°C) given by T_o = 0.75B + 311, where B represents the heating rate (°C/min). The temperature at which the weight-loss rate was at a maximum was T_p = 0.91B + 320, and the temperature at which degradation was completed was T_f = 1.00B + 325. In the thermal degradation of P(HB–HV) (70:30), T_o = 0.96B + 308, T_p = 0.99B + 320, and T_f = 1.09B + 325. In the thermal degradation of P(HB–HHx) (85:15), T_o = 1.11B + 305, T_p = 1.10B + 319, and T_f = 1.16B + 325. The derivative thermogravimetry curves of PHB, P(HB–HV), and P(HB–HHx) confirmed only one weight-loss step change. The incorporation of 30 mol % 3-hydroxyvalerate (HV) and 15 mol % 3-hydroxyhexanoate (HHx) components into the polyester increased the various thermal temperatures T_o, T_p, and T_f relative to those of PHB by 3–12°C (measured at B = 40°C/min). DSC measurements showed that the incorporation of HV and HHx decreased the melting temperature relative to that of PHB by 70°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 90–98, 2001     

Biodegradable polymer blends of poly(3-hydroxybutyrate) and poly(DL-lactide)-co-poly(ethylene glycol)

The melting and crystallization behavior and phase morphology of poly(3-hydroxybutyrate) (PHB) and poly(DL-lactide)-co-poly(ethylene glycol) (PELA) blends were studied by DSC, SEM, and polarizing optical microscopy. The melting temperatures of PHB in the blends showed a slight shift, and the melting enthalpy of the blends decreased linearly with the increase of PELA content. The glass transition temperatures of PHB/PELA (60/40), (40/60), and (20/80) blends were found at about 30°C, close to that of the pure PELA component, during DSC heating runs for the original samples and samples after cooling from the melt at a rate of 20°C/min. After a DSC cooling run at a rate of 100°C/min, the blends showed glass transitions in the range of 10–30°C. Uniform distribution of two phases in the blends was observed by SEM. The crystallization of PHB in the blends from both the melt and the glassy state was affected by the PELA component. When crystallized from the melt during the DSC nonisothermal crystallization run at a rate of 20°C/min, the temperatures of crystallization decreased with the increase of PELA content. Compared with pure PHB, the cold crystallization peaks of PHB in the blends shifted to higher temperatures. Well-defined spherulites of PHB were found in both pure PHB and the blends with PHB content of 80 or 60%. The growth of spherulites of PHB in the blends was affected significantly by 60% PELA content. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 1849–1856, 1997     

聚(3-羟基丁酸酯)的共混改性

聚（3－羟基丁酸酯）（PHB）的共混改性是目前研究的一个重要，本文主要从热行为，结晶行为等方面论述了研究较多的PHB与热塑性高聚物，橡胶及多糖类的共混行为及其结果。     

Biodegradable polymer blends of poly(3-hydroxybutyrate) and starch acetate

The thermal behaviour and phase morphology of poly(3-hydroxybutyrate) (PHB) and starch acetate (SA) blends have been studied by differential scanning calorimetry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy and polarizing optical microscopy. PHB/SA blends were immiscible. The melting temperatures of PHB in the blends showed some shift with increase of SA content. The melting enthalpy of the PHB phase in the blend was close to the value for pure PHB. The glass transition temperatures of PHB in the blends remained constant at 9°C. The FTIR absorptions of hydroxyl groups of SA and carbonyl groups of PHB in the blends were found to be independent of the second component at 3470cm^-1 and 1724cm^-1, respectively. The crystallization of PHB was affected by the addition of the SA component both from the melt on cooling and from the glassy state on heating. The temperature and enthalpy of non-isothermal crystallization of PHB in the blends were much lower than those of pure PHB. The crystalline morphology of PHB crystallized from the melt under isothermal conditions varied with SA content. The cold crystallization peaks of PHB in the blends shifted to higher temperatures compared with that of pure PHB. ©1997 SCI     

聚3-羟基丁酸酯降解技术研究进展

综述了目前聚3-羟基丁酸酯（poly-3-hydroxybutyrate,PHB）的几种主要降解技术,包括热裂解、水解、溶剂降解和酶解等。重点介绍了各种降解技术的产物分布和反应机理,并对影响PHB热稳定性的主要因素进行了总结和讨论。各种技术的所需反应温度总体趋势为：热裂解>水解≥溶剂降解>酶解。PHB热解工艺简单,通常情况下PHB主要降解为巴豆酸和其低聚物,过高反应温度（>500℃）则使PHB分解为二氧化碳和丙烯。水解和溶剂降解都是以针对性地断开PHB酯键为出发点,以获得高产率的PHB单体（3-羟基丁酸、巴豆酸）或其酯类化合物（如巴豆酸甲酯）。与热解、水解和溶剂降解技术相比,酶解法限制因素较多且工艺成本高,需要新的技术突破。提出了两个需进一步重点研究的方向：①PHB催化热解脱羧制备高品位液体燃料;②直接转化富含PHB的微生物为高价值化学品。     

聚(3-羟基丁酸酯-co-4-羟基丁酸酯)研究进展

介绍了生物可降解材料聚(3-羟基丁酸酯-co-4-羟基丁酸酯)(P(3HB-co-4HB))的性能及特点;综述了针对P(3HB-co-4HB)加工温度窄、脆性大、成本高等缺点而进行的增塑改性、扩链改性、共混改性的技术进展以及P(3HB-co-4HB)纺丝成纤技术;阐述了利用P(3HB-co-4HB)可塑性、生物降解性和生物相容性等在医疗领域的应用情况及发展前景;指出P(3HB-co-4HB)的研究将集中在其材料加工流动性、结晶性能的改善及其纤维加工技术与纤维表面整理技术等方面。     

聚(3-羟基丁酸酯)的化学改性研究进展

评述了降解塑料聚(3 羟基丁酸酯)(PHB)近年来在化学改性方面的研究进展情况,特别就PHB化学改性的方法和产物的性能进行了总结和评述。PHB化学改性的方法包括辐射聚合、大单体反应改性、反应性共混等。PHB化学改性可通过分子设计合成特定结构的PHB共聚物,具有物理共混无法比拟的优势,特别是在组织工程领域有着广泛的应用前景。     

Some properties of poly(3-hydroxybutyrate)–poly(3-hydroxyvalerate) blends

The melting, crystallization and dynamic mechanical behaviour of blends of bacterially produced poly[D (–)-3-hydroxybutyrate] (PHB) and poly[D (–)-3-hydroxyvalerate] (PHV) have been investigated. Results showed that melt-pressed PHB–PHV blends contained phase-separated domains in the melt which subsequently crystallized as PHB and PHV type spherulites respectively. The two melting regions detected by DTA related to separate melting of PHB and PHV crystallites, which were almost unaffected by the blend composition. The mechanical behaviour of a random copolymer of PHB/HV was compared with that of a blend of almost the same composition, and found to be markedly different.     

Microbial synthesis and properties of poly(3-hydroxybutyrate-co-4-hydroxybutyrate)

Microbial synthesis of copolymers of [R]-3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB), P(3HB-co-4HB), by Alcaligenes eutrophus, Alcaligenes latus, and Comamonas acidovorans from various carbon sources has been studied. The copolyester compositions varied from 0 to 100 mol% 4HB, depending on the microorganism and the combination of carbon substrates supplied. The thermal and physical properties of compositions with 0–100 mol% 4HB were investigated. The copolyesters represented a wide variety of polymeric materials, from hard crystalline plastic to very elastic rubbers, depending on composition. The copolyester films with high 4HB fractions (64–100 mol% 4HB) exhibited the characteristics of a thermoplastic elastomer, and the tensile strength increased from 17 to 104 MPa as the 4HB fraction increased. The enzymatic degradation of P(3HB-co-4HB) films was studied in an aqueous solution of extracellular polyhydroxybutyrate (PHB) depolymerase from Alcaligenes faecalis or lipase from Rhizopus delemer. The erosion rate of P(3HB-co-4HB) films was strongly dependent on the copolymer composition. In addition, environmental degradation of P(3HB-co-4HB) films in sea water was investigated.     

聚丙烯纤维在聚3-羟基丁酸酯与木质素对甲酚复合膜中的改性作用研究

研究了聚3-羟基丁酸酯/聚丙烯纤维(PHB/PP)复合膜和PHB/PP/木质素对甲酚复合膜的力学和热力学性能的影响,分别探讨了PP纤维和木质素对甲酚的添加量对复合膜性能的影响。结果表明,PP纤维含量为8 %且木质素对甲酚含量为3 %时,PHB/PP/木质素对甲酚复合膜的综合性能最佳,适量的PP纤维改善了PHB的拉伸强度,并且木质素对甲酚一定程度上改善了复合膜的热降解性能。