聚碳酸亚丙酯-聚乙二醇复合材料的制备与性能

通过聚碳酸亚丙酯(PPC)与聚乙二醇(PEG)的共混,提高PPC的热性能、亲水性和降解性能。通过1HNMR、FT-IR、XRD研究了共混物的相容性,表明聚合物之间没有发生化学反应,两者之间为简单的物理共混,相容性较好。共混物热性能的测试结果表明,共混物的玻璃化转变温度最高为61℃,比PPC提高了39℃,Td50%和最高分解速率时的温度都在242～262℃范围内,高于PPC的Td50%(235℃)和Tmax(238℃);共混物亲水性是PPC的12～33倍,其溶液降解性最多比PPC提高16倍,而生物降解性能至少比PPC提高4～6倍。     

聚碳酸亚丙酯改性复合材料的性能

通过溶液共混法实现聚碳酸亚丙酯(PPC)与聚乙二醇(PEG)的共混改性,提高PPC的热性能。通过1HNMR、FTIR研究了共混物的相容性,表明聚合物之间没有发生化学反应,两者之间为简单的物理共混,相容性较好,而且共混物的亲水性随着PEG组分的增加而增强。热性能测试结果表明,共混物的玻璃化转变温度(Tg)和热分解温度(Td)都比PPC高,Tg和Td95%最高分别达到51℃和410℃,比PPC提高了29℃和130℃。可用于制备高性能的包装材料。     

聚碳酸亚丙酯／纳米氧化锌复合材料制备及性能研究

通过转矩流变仪制备了PPC／纳米氧化锌复合材料,利用红外光谱（FTIR）、差示扫描量热（DSC）、热重分析（TG）研究了复合材料的性能。实验结果表明添加纳米氧化锌,抑制了PPC“解拉链”降解;复合材料的玻璃化转变温度和热分解速率最大温度随着共混物中纳米氧化锌加入量的增加而逐渐提高,分别达到31．15℃和263．10℃,比纯PPC提高了17．66℃和49．4℃。     

聚碳酸亚丙酯/聚甲基丙烯酸甲酯复合材料制备及性能研究

通过转矩流变仪制备了聚碳酸亚丙酯/聚甲基丙烯酸甲酯(PPC/PMMA)复合材料,利用红外光谱(FTIR)、差示扫描量热(DSC)、热重分析(TG)研究了复合材料的性能。结果表明:140℃下添加PMMA,抑制了PPC"解拉链"降解;复合材料的玻璃化转变温度和热分解速率最大温度随着共混物中PMMA加入量的增加而逐渐提高,分别达到38.40℃和268.10℃,比纯PPC提高了25.01℃和54.4℃。     

聚碳酸亚丙酯/有机水滑石复合材料的制备及性能研究

利用马来酸酐（MAH）作为聚碳酸亚丙酯（PPC）的封端剂,采用熔融共混法制备了PPC /有机水滑石（OLDH）复合材料。当复合材料中OLDH的含量达到4 %（质量分数,下同）时,复合材料的5 %失重温度、 95 %失重温度、失重最大速率温度较纯PPC分别提高了49.1、70.2、49.3 ℃,玻璃化转变温度由18.3 ℃增加到了22.7 ℃,并且少量层状粒子OLDH的加入可以提高聚合物的力学性能以及阻隔性能。     

聚碳酸亚丙酯/聚乙烯醇共混复合材料的性能

采用熔融共混挤出的方式制备了可生物降解的聚碳酸亚丙酯(PPC)/聚乙烯醇(PVA)复合材料。运用差示扫描量热仪(DSC)、热失重分析仪(TGA)、扫描电子显微镜(SEM)和万能试验机分别研究了复合材料的相容性、热稳定性、微观形态以及力学性能。结果表明:复合体系中材料的相容性较好,改性PVA的引入提高了复合材料的热稳定性和拉伸强度,当改性PVA的质量分数为50%时,拉伸强度达到39.2 MPa,提高了约177%。     

细菌纤维素增强改性聚碳酸亚丙酯复合材料的制备及性能

将细菌纤维素(BC)作为增强材料加入聚碳酸亚丙酯(PPC)基体中,采用溶液浇铸法制备了PPC/BC复合薄膜材料,研究了BC用量对PPC拉伸性能、热稳定性能及降解性能的影响。结果表明:随着BC用量的增加,PPC/BC复合薄膜的拉伸强度和热稳定性能明显提高,降解速率减慢。     

聚碳酸亚丙酯/纤维素复合材料的制备和性能

采用双螺杆挤出机制备了完全可生物降解的聚碳酸亚丙酯/纤维素复合材料,并对复合材料的性能进行表征和研究。研究结果表明:聚碳酸亚丙酯和纤维素之间的相容性较差,纤维素含量较少时,可以均匀分散在聚碳酸亚丙酯基体中;当纤维素含量增加时,纤维素会大量团聚。聚碳酸亚丙酯/纤维素复合材料的热稳定性、玻璃化转变温度和力学性能等随着纤维素含量的增加也随之提高。纤维素质量分数为30%时,复合材料的T5%、T50%和Tmax分别达到256.6、313.1和308.0℃,比纯PPC提高了约50℃;复合材料的玻璃化转变温度为48℃,与纯PPC相比提高了16℃。另外,复合材料的拉伸强度为45 MPa,大约是聚碳酸亚丙酯的5.6倍,同时复合材料的维卡软化点为43℃,比聚碳酸亚丙酯提高了11℃。     

水滑石改性聚碳酸亚丙酯复合材料的力学性能与相态调控

将γ-氨丙基三乙氧基硅烷(KH550)改性的水滑石(KH550-LDH)与聚碳酸亚丙酯(PPC)、异氰尿酸三缩水甘油酯(TGIC)熔融共混挤出制备PPC/KH550-LDH/TGIC复合材料。考察了水滑石(LDH)表面改性处理以及KH550-LDH和TGIC添加量对复合材料的力学性能、熔体流动性能、相容性的影响。结果表明,KH550-LDH与PPC有着更好的相容性,PPC/KH550-LDH/TGIC复合材料的综合性能要优于PPC/LDH/TGIC复合材料。以树脂100份为基准,当KH550-LDH和TGIC的质量份数分别为10份和3份时,复合材料具有最佳的力学性能,拉伸强度达到18.9 MPa,比纯PPC提高84%,同时复合材料具有良好的相容性。     

聚碳酸亚丙酯共混改性研究进展

聚碳酸亚丙酯(polypropylene carbonate,PPC)是一种新型可完全生物降解的热塑性脂肪族聚碳酸酯。与其它聚合物进行共混改性是改善PPC基材综合性能的有效手段。本文从PPC的合成工艺、性能特点和应用出发,综述了近十年来PPC与可降解聚合物、非降解聚合物、无机粒子等进行溶剂共混和熔融共混改性的研究进展;并对PPC将来的发展作了展望。     

Improved thermal stability and mechanical properties of poly(propylene carbonate) by reactive blending with maleic anhydride

To extend the application of a carbon dioxide sourced environmental friendly polymer: poly (propylene carbonate) (PPC), a small amount of maleic anhydride (MA) was melt blended to end‐cap with PPC to improve its thermal stability and mechanical properties. Thermal and mechanical properties of end‐capped PPC were investigated by TGA, GPC, mechanical test, and DMA. TGA and titration results demonstrate that PPC can be easily end‐capped with MA through simple melt blending. TGA results show that the thermal degradation temperature of PPC could be improved by around 140°C by adding MA. GPC measurement indicates that the molecular weight of PPC can be maintained after blending with MA, where pure PPC experiences a dramatic degradation in molecular weight during melt process. More importantly, the tensile strength of PPC after blending with MA was found to be nearly eight times higher than that of pure PPC. It has approached the mechanical properties of polyolefin polymers, indicating the possibility of replacing polyolefin polymers with PPC for low temperature applications. The method described here could be used to extend the applications of PPC and fight against the well known global warming problem. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

FTIR study of poly(propylene carbonate)/bisphenol A blends

A systematic investigation by FTIR spectroscopy was undertaken on blends of poly(propylene carbonate) (PPC) and bisphenol A (BPA). It provided direct evidence of the hydrogen bond (H‐bond) between BPA O? H groups and PPC C?O groups. Using a curve‐fitting method, qualitative as well as quantitative information concerning this H‐bond interaction was obtained. The inter‐H‐bond in PPC/BPA blends was weaker than the self‐H‐bond in BPA. The absorptivities of the free and the H‐bonded C?O groups were nearly equal. The fraction of H‐bonded C?O in the blends increased with BPA content and leveled off at a value close to 40 %. Finally, FTIR–temperature measurements of pure PPC and a representative blend were reported: by monitoring the peak areas of C?O absorptions, the dissociation of the inter‐H‐bonds and the thermal degradation of PPC were observed. It revealed that the presence of BPA clearly retarded the thermal degradation of PPC. Copyright © 2004 Society of Chemical Industry     

PPC/PDAP共混膜的制备和性能

将过氧化二异丙苯(DCP)置于特定温度下,引发邻苯二甲酸二烯丙酯(DAP)在聚碳酸亚丙酯(PPC)溶液中聚合,制备得到聚碳酸亚丙酯/聚邻苯二甲酸二烯丙酯(PPC/PDAP)共混膜。采用红外光谱仪(FTIR)、X射线衍射仪(XRD)、差示扫描量热仪(DSC)、热重分析仪(TGA)、万能试验机和水蒸气透过率测试仪对共混膜的红外吸收、结晶性、热、力学和阻隔性能进行了表征。结果表明,通过DAP的聚合,提高了PPC的结晶性,使PDAP在PPC基体中形成交联网络,提高了共混膜的热、力学和阻隔性能。相比纯PPC,当DAP含量为20%时,共混膜的玻璃化转变温度和拉伸强度分别提高了5.3℃和266%;当DAP含量为40%时,共混膜的失重5%热分解温度提高了50.9℃,透湿系数下降了25%,因此,阻隔性能得到了提升。     

苎麻纤维增强聚碳酸亚丙酯复合材料的工艺与性能研究

采用苎麻纤维和聚碳酸亚丙酯制备了可降解复合材料,讨论了苎麻长度、含量对苎麻/聚碳酸亚丙酯复合材料机械性能的影响,并借助扫描电子显微镜对复合材料的冲击断口形貌进行了观察.结果表明:苎麻经碱液处理后,苎麻/聚碳酸亚丙酯复合材料的拉伸性能和冲击性能有了明显提高.     

加工温度与助剂对聚碳酸亚丙酯热降解性影响

通过特性黏度法研究加工温度与助剂对聚碳酸亚丙酯(PPC)热降解性的影响,并采用凝胶渗透色谱法评价特性黏度法结果的可靠性。结果表明:PPC对温度敏感,温度升高,特性黏度变低,相对分子质量变低。当加工温度从120℃升高到160℃,PPC的特性黏度从2.16 dL/g下降到1.31 dL/g,继续升高到200℃时,特性黏度从1.31dL/g下降到1.18 dL/g,说明温度越高,PPC特性黏度越低,热降解加剧,在120—160℃下降解速率较在160—200℃下快。在加工温度为140℃时,PPC的特性黏度为1.62 dL/g,PPC/MAH和PPC/AO1010的特性黏度比PPC的特性黏度分别提高了0.65 dL/g和0.25 dL/g,说明封端剂MAH、热稳定剂AO1010的加入能抑制PPC的热降解,提高PPC的热稳定性。采用特性黏度法研究PPC热降解的方法是可行的,且经济、方便、快捷,是研究PPC热降解性、可实现在线分析的一种良好方法。     

Study on nitrile-butadiene rubber/poly(propylene carbonate) elastomer as coupling agent of poly (vinyl chloride)/poly (propylene carbonate) blends. I. Effect on mechanical properties of blends

Nitrile-butadiene rubber/poly(propylene carbonate) (NBR-PPC) elastomer was studied as a coupling agent of the blends of poly(vinyl chloride) (PVC) with poly(propylene carbonate) (PPC). It greatly improved the PVC/PPC system mechanical properties that were dependent on the amount and composition of the coupling agent. When the coupling agent consisted of a 70/30 ratio of NBR/PPC (in which NBR had 34% nitrile content) and 2.5 phr of benzoyl peroxide (BPO) initiator and underwent a prevulcanization, the blends of PVC/PPC displayed excellent mechanical properties by adding 8 phr of the coupling agent. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 1107–1111, 1997     

Partially miscible poly(lactic acid)‐ blend‐poly(propylene carbonate) filled with carbon black as conductive polymer composite

BACKGROUND: Conductive polymer composites (CPCs) can be obtained by filling polymer matrices with electrically conductive particles, and have a wide variety of potential applications. In the work reported, the biodegradable polymer poly(lactic acid) (PLA) as a partially miscible blend with poly(propylene carbonate) (PPC) was used as a polymer matrix. Carbon black (CB) was used as the conducting filler. RESULTS: Fourier transform infrared spectroscopy revealed interactions between matrix and CB filler; this interaction was stronger in PPC‐blend‐CB than in PLA‐blend‐CB composites. A rheology study showed that low‐viscosity PPC could improve the fluidity of the CPCs, but decrease that of CB. With increasing CB content, the enforcement effect, storage modulus and glass transition temperature increased, but the elongation at break decreased. CPCs exhibited the lowest electrical percolation thresholds of 1.39 vol.% CB when the content of PPC in PLA‐blend‐PPC was 40 wt%. The conductivity of CPCs containing 5.33 vol.% CB and 40 wt% PPC reached 1.57 S cm^?1. Scanning electron microscopy revealed that CB exhibits a preference for dispersion in the low‐viscosity phase (PPC) of the multiphase matrix. CONCLUSION: In the presence of CB, partially miscible PLA‐blend‐PPC could form multi‐percolation CPCs. Moreover, the combination of PLA and PPC with CB broadens novel application of both renewable polymers and CPCs. Copyright © 2008 Society of Chemical Industry     

Thermal and Mechanical Properties of PA66 Short Fiber-Reinforced Poly(propylene carbonate) Composite via Hydrogen Bonding Interaction and Its Rheological Responses

Poly(propylene carbonate) (PPC) was reinforced by polyamide 66 short fiber (SF-PA66) through hydrogen-bonding interaction. The tensile and impact strength, thermal stability of composites increased when the SF-PA66 content ranges from 5 to 20%, then decreased at 30%. The increment in impact strength, decomposition temperature of 5% mass loss and glass transition temperature of PPC/20%PA66 is 315.81%, 32.2 and 3.8°C, respectively. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy results illuminate that the introduction of hydrogen-bonding interaction between PPC and SF-PA66. Moreover, the network structure formed when SF-PA66 content is higher than 20 wt%. It is confirmed by rheological responding curves that a plateau at low angle frequency occurs. In addition, a significant aggregation of SF-PA66 occurs when its content is 30 wt%, which causes the decrease in mechanical and thermal properties of PPC/SF-PA66 composites.     

生物降解PPC/HA复合材料的制备与性能研究

将羟基磷灰石（HA）用硅烷偶联剂KH570处理，然后与聚碳酸亚丙酯（PPC）进行共混，制备了一种可生物降解、生物相容性好的PPC／HA复合材料，研究了其在不同混合比例时的力学性能、玻璃化转变温度及其内部结构。该复合材料力学强度介于塑料和橡胶之间，具备良好的力学回复特性和一定的形状记忆效应，HA为20％（质量分数，下同）时，断裂伸长率达到315％，弹性回复率可达98％。DSC分析表明，复合材料的玻璃化转变温度受姒的影响不大，在35℃左右，随HA含量的不同略微有一些变化。SEM观察到在拉伸过程中，复合材料内部出现一种板块与微纤复合结构，这种结构对材料的力学性能变化有一定影响，可能也是力学回复特性产生的原因。