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Poly(propylene carbonate)(PPC) was melt blended in a batch mixer with poly(butylene carbonate)(PBC) in an effort to improve the toughness of the PPC without compromising its biodegradability and biocompatibility. DMA results showed that the PPC/PBC blends were an immiscible two-phase system. With the increase in PBC content, the PPC/PBC blends showed decreased tensile strength, however, the elongation at break was increased to 230% for the 50/50 PPC/PBC blend. From the tensile strength experiments, the Pukanszky model gave credit to the modest interfacial adhesion between PPC and PBC, although PPC/PBC was immscible. The impact strength increased significantly which indicated the toughening effects of the PBC on PPC. SEM examination showed that cavitation and shear yielding were the major toughening mechanisms in the blends subjected the impact tests. TGA measurements showed that the thermal stability of PPC decreased with the incorporation of PBC. Rheological investigation demonstrated that the addition of PBC reduced the value of storage modulus, loss modulus and complex viscosity of the PPC/PBC blends to some extent. Moreover, the addition of PBC was found to increase the processability of PPC in extrusion. The introduction of PBC provided an efficient and novel toughened method to extend the application area of PPC. 相似文献
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To assess the compatibility of blends of synthetic poly(propylene carbonate) (PPC), with a natural bacterial poly(3-hydroxybutyrate) (PHB), a simple casting procedure of blend was used. poly(3-hydroxybutyrate)/poly(propylene carbonate) blends are found to be incompatible according to DSC and DMA analysis. In order to improve the compatibility and mechanical properties of PHB/PPC blends, poly(vinyl acetate) (PVAc) was added as a compatibilizer. The effects of PVAc on the thermal behavior, morphology, and mechanical properties of 70PHB/30PPC blend were investigated. The results show that the melting point and the crystallization temperature of PHB in blends decrease with the increase of PVAc content in blends, the loss factor changes from two separate peaks of 70PHB/30PPC blend to one peak of 70PHB/30PPC/12PVAc blend. It is also found that adding PVAc into 70PHB/30PPC blend can decrease the size of dispersed phase from morphology analysis. The result of tensile properties shows that PVAc can increase the tensile strength and Young’s modulus of 70PHB/30PPC blend, and both the elongation at break and the tensile toughness increase significantly with PVAc added into 70PHB/30PPC. 相似文献
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Poly(propylene carbonate)(PPC) was blended with polylactide(PLA) and poly(1,2-propylene glycol adipate)(PPA) using a twin screw extruder. Then the PPC/PLA/PPA films were prepared using the blown film technique. DMA results showed that PPA could act as a plasticizer and improve the miscibility between PPC and PLA. Crystal morphology displayed that blending PLA with the amorphous PPC led to a decrease of the spherulite size of PLA. The results of mechanical tests indicated that PPC-rich films showed high elongation at break and PLA-rich films showed high tear strength and good optical properties. The content of PPC and PLA significantly affected the physical properties of the films. With increasing PPC content, the melt strengths of the PPC/PLA/PPA films were enhanced. These findings contributed to the biodegradable materials application for designing and manufacturing polymer packaging. 相似文献
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Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(propylene carbonate) (PPC) were blended by solvent casting method into films at various weight ratios in order to obtain materials with properties more suitable for blood vessel tissue engineering than pure PHBHHx alone. FTIR and XRD analysis indicated the crystal structure of PHBHHx was not altered but the crystallinity was reduced by the interfusion of PPC. Mechanical properties of the films were improved significantly by blending with PPC. A lower elastic modulus and a higher elongation at break were obtained with the increase of PPC content. Wettability, fibronectin adsorption and adhesion of rabbit aorta smooth muscle cells (RaSMCs) on blend films were similar to or better than that on PHBHHx film. All these results showed promises of PHBHHx/PPC blended materials as scaffold material for blood vessel tissue engineering. 相似文献
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In order to improve the flexibility of poly(propylene carbonate) (PPC), poly(1,2-propylene succinate) (PPSu) was used to plasticize PPC in a batch mixer. The effects of PPSu on the miscibility, thermal stability, mechanical and theological properties of the blends were investigated. PPC was partially miscible with PPSu. It was demonstrated that PPSu decreased the glass transition temperature and melt viscosity of PPC, as shown in the DSC and rheological curves. With the increase in PPSu content, the PPC/PPSu blends showed decreased tensile strength, however, the elongation at break was increased to 1100% for the 70/30 PPC/PPSu blend. The introduction of PPSu provided an efficient and novel plasticization method to extend the application area of PPC. 相似文献
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聚碳酸1,2-丙二酯/聚琥珀酸丁二酯/邻苯二甲酸二烯丙酯共混体系的研究 总被引:1,自引:0,他引:1
采用熔融共混的方法制备了聚碳酸1,2-丙二酯(PPC)/聚琥珀酸丁二酯(PBS)共混物和PPC/PBS/DAOP(邻苯二甲酸二烯丙酯)增塑共混物,对共混物的相容性、热性能、结晶性和物理机械性能进行了初步研究.研究结果表明PPC/PBS共混物为不相容体系,PPC对PBS的结晶度影响很小;PBS的加入提高了共混物的起始热分解温度(Td-5%),当共混物中PBS含量从10%增加到90%时,共混物的Td-5%可分别增加15℃到59℃.DAOP对PPC/PBS共混物有增塑作用,当PPC/PBS/DAOP的比例从30/70/0变化到30/70/30时,共混物玻璃化转变温度(Tg)下降了36.9℃.与PPC/PBS共混物相比,组成优化的DAOP增塑共混物PPC/PBS/DAOP(PPC/PBS/DAOP=30/70/5)的断裂伸长率和断裂能最大可提高31倍和34倍,分别达到655.1%和3.4 J/mm2,因此引入DAOP尽管使共混材料的热稳定性有所下降,但拓宽了PPC/PBS共混材料的使用温度窗口. 相似文献
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Biodegradable Foaming Material of Poly(butylene adipate-co-terephthalate) (PBAT)/Poly(propylene carbonate) (PPC) 总被引:1,自引:0,他引:1
Han-Lin Tian Ze-Peng Wang Shi-Ling Jia Hong-Wei Pan Li-Jing Han Jun-Jia Bian Ying Li Hui-Li Yang Hui-Liang Zhang 《高分子科学》2022,40(2):208-219
A biodegradable blend foaming material of poly(butylene adipate-co-terephthalate)(PBAT)/poly(propylene carbonate)(PPC)was successfully prepared by chemical foaming agent and screw extrusion method.First,PBAT was modified by bis(tert-butyl dioxy isopropyl)benzene(BIBP)for chain extension,and then the extended PBAT(E-PBAT)was foamed with PPC using a twin(single)screw extruder.By analyzing the properties of the blends,we found that Young’s modulus increased from 58.8 MPa of E-PBAT to 244.7 MPa of E-PBAT/PPC 50/50.The viscosity of the polymer has a critical influence on the formation of cells.Compared with neat PBAT(N-PBAT),the viscosity of E-PBAT increased by 3396 Pa·s and E-PBAT/PPC 50/50 increased by 8836 Pa·s.Meanwhile,the dynamic mechanical analysis(DMA)results showed that the storage modulus(E’)at room temperature increased from 538 MPa to 1650 MPa.The various phase morphologies(“sea-island”,“quasi-co-continuous”and“cocontinuous”)and crystallinity of the blends affected the spread velocity of gas and further affected the foaming morphology in E-PBAT/PPC foam.Therefore,through the analysis of phase morphology and foaming mechanism,we concluded that the E-PBAT/PPC 70/30 component has both excellent strength and the best foaming performance. 相似文献
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选用辛酸亚锡[Sn(Oct)2]和钛酸四丁酯(TBT)作为聚乳酸(PLA)/聚碳酸亚丙酯(PPC)的酯交换反应催化剂, 研究了溶液条件下单一催化剂及复合催化剂对PLA/PPC酯交换反应的催化作用. 通过对反应产物的分子结构、 热力学及流变学行为进行分析, 结果发现, 无论在单一催化剂还是复合催化剂作用下, PLA与PPC分子间均发生了酯交换反应, 同时伴随着断链反应. 其中, 当Sn(Oct)2作为单一催化剂或Sn(Oct)2/TBT作为复合催化剂时, 样品更倾向发生断链反应而非显著的酯交换反应. 进一步分析纯样品在催化剂Sn(Oct)2或TBT作用下的反应情况, 结果发现, PPC在反应最初阶段以高分子量的分子链断链为主, 且会发生明显的解拉链降解, 从而导致PLA/PPC在等质量比时酯交换反应程度不高, 这为今后更好地研究PLA/PPC酯交换反应提供了思路. 相似文献
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通过己内酯和氨基己酸开环、缩合反应制备了酯段含量为81%的线性聚酯酰胺(PEA),并用熔融共混的方法制备了PEA/聚碳酸亚丙酯(PPC)共混物,考察了PEA的引入对共混体系相容性、热力学稳定性和机械性能的影响。 结果表明,PEA与PPC之间有较好的相容性,共混物的热力学稳定性比PPC有显著提高,当PEA质量分数为3%时,共混体系的起始分解温度(T-5%)和最大分解速率时的温度(Tmax)比PPC分别提高了52.7%和46.4%。 通过调节PEA的含量可以使共混体系同时达到增强和增韧的效果。 相似文献
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Poly(propylene carbonate) (PPC),the copolymerization product of carbon dioxide and propylene oxide,was chlorinated for the first time in our laboratory.Nuclear magnetic resonance (NMR) spectroscopy and ion chromatography test showed that chlorine atoms were successfully introduced onto the polymer chains of PPC.We named this newborn polymer material as chlorinated poly(propylene carbonate) (CPPC).It is worth noting that the reaction conditions of the chlorination of PPC were quite mild,which could be easily and simply realized at industrial level.What is more important is that CPPC possessed many more distinguished properties in solubility,wettability,adhesiveness,and gas barrier compared with PPC.For example,the bonding strength of CPPC as thermal adhesive is nearly four times higher than that of PPC for wood,stainless steel and glass.The oxygen permeability coefficient of CPPC exhibits a decrease of 33% compared with that of PPC.Moreover,CPPC is quite stable in air,whereas it could be well biodegraded in soil compared with PPC.These results indicated that CPPC could be widely used in the fields of coating,adhesive,barrier materials and so on,which could greatly promote the development of PPC industry. 相似文献
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Li Ming Dong Gong Xiong Liao Ming Jing Wang Xi Gao Jian 《中国化学快报》2008,19(2):230-232
Block copolymers with different backbone compositions have been prepared by the condensation of dimethylamino terminated poly(dimethylsiloxane) (PDMS) and hydroquinone terminated poly(phthalazinone ether nitrile) (PPEN) in the presence of chlorobenzcne/N-methyl pyrrolidone (NMP) as solvents. The products were characterized by FTIR, ^1H NMR and gel permeation chromatography. Differential scanning calorimetry analysis indicated that the block copolymers showed separated microphase. 相似文献
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Biodegradable poly(propylene carbonate)/layered double hydroxide composite films with enhanced gas barrier and mechanical properties 总被引:1,自引:0,他引:1
Relatively well crystallized and high aspect ratio Mg-Al layered double hydroxides(LDHs) were prepared by coprecipitation process in aqueous solution and further rehydrated to an organic modified LDH(OLDH) in the presence of surfactant. The intercalated structure and high aspect ratio of OLDH were verified by X-ray diffraction(XRD) and scanning electron microscopy(SEM). A series of poly(propylene carbonate)(PPC)/OLDH composite films with different contents of OLDH were prepared via a melt-blending method. Their cross section morphologies, gas barrier properties and tensile strength were investigated as a function of OLDH contents. SEM results show that OLDH platelets are well dispersed within the composites and oriented parallel to the composite sheet plane. The gas barrier properties and tensile strength are obviously enhanced upon the incorporation of OLDH. Particularly, PPC/2%OLDH film exhibits the best barrier properties among all the composite films. Compared with pure PPC, the oxygen permeability coefficient(OP) and water vapor permeability coefficient(WVP) is reduced by 54% and 17% respectively with 2% OLDH addition. Furthermore, the tensile strength of PPC/2%OLDH is 83% higher than that of pure PPC with only small lose of elongation at break. Therefore, PPC/OLDH composite films show great potential application in packaging materials due to its biodegradable properties, superior oxygen and moisture barrier characteristics. 相似文献
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Mechanical,thermal and rheological properties and morphology of poly (lactic acid)/poly (propylene carbonate) blends prepared by vane extruder 下载免费PDF全文
In this study, the poly (lactic acid) (PLA) and poly (propylene carbonate) (PPC) blends with different compositions were prepared by a novel vane extruder based on elongation rheology. The mechanical properties, morphologies, crystallization behavior, thermal stability, and rheological properties of the blends were investigated. Mechanical test showed that PLA could be toughened by PPC to some extent, and the impact strength of the PLA was maximized when PPC content was about 30%. Differential scanning calorimetry analysis revealed that PPC had little effect on the melting process, the crystallization behavior of PLA component in the blend was improved, and the cold crystallizability of PLA decreased with the increase of PPC content when the PPC content was less than 50%. Thermogravimetry analysis showed that the thermal stability of the blends was improved by compounding with PLA. Scanning electron microscope showed that the dispersion of PLA droplets in PPC matrix was better than that of PPC droplets in PLA matrix. Rheological test showed that the melt viscosity of the pure PLA and the blend with 10% PPC was insensitive to shear rate, and the blends melt appeared shear thinning phenomenon with the increase of PPC content. It also showed that the blends microstructure changed with the addition of PPC and the blends with PPC content in a certain range had similar stress relaxation mechanism. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Paul C. Mengnjoh Harry L. Frisch 《Journal of polymer science. Part A, Polymer chemistry》1989,27(10):3363-3370
Simultaneous full and pseudo- interpenetrating polymer networks of poly(2,6-dimethyl-1,4 phenylene oxide) (PPO) and a poly(urethane acrylate) (PUA) have been synthesized and characterized by differential scanning calorimetry, ultimate mechanical properties, and electron microscopy. No evidence of phase separation was detected in both the full and pseudo- PPO/PUA networks. The networks exhibited a single glass transition temperature at all the compositions studied. A maximum in tensile strength to break was observed at 25 PPO/75 PUA composition by weight percent. 相似文献
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Brunner CT Baran ET Pinho ED Reis RL Neves NM 《Colloids and surfaces. B, Biointerfaces》2011,84(2):77-507
Poly(butylene succinate) (PBSu), poly(butylene succinate-co-adipate) (PBSA) and poly(butylene terephthalate-co-adipate) (PBTA) microcapsules were prepared by the double emulsion/solvent evaporation method. The effect of polymer and poly(vinyl alcohol) (PVA) concentration on the microcapsule morphologies, drug encapsulation efficiency (EE) and drug loading (DL) of bovine serum albumin (BSA) and all-trans retinoic acid (atRA) were all investigated. As a result, the sizes of PBSu, PBSA and PBTA microcapsules were increased significantly by varying polymer concentrations from 6 to 9%. atRA was encapsulated into the microcapsules with an high level of approximately 95% EE. The highest EE and DL of BSA were observed at 1% polymer concentration in values of 60 and 37%, respectively. 4% PVA was found as the optimum concentration and resulted in 75% EE and 14% DL of BSA. The BSA release from the capsules of PBSA was the longest, with 10% release in the first day and a steady release of 17% until the end of day 28. The release of atRA from PBSu microcapsules showed a zero-order profile for 2 weeks, keeping a steady release rate during 4 weeks with a 9% cumulative release. Similarly, the PBSA microcapsules showed a prolonged and a steady release of atRA during 6 weeks with 12% release. In the case of PBTA microcapsules, after a burst release of 10% in the first day, showed a parabolic release profile of atRA during 42 days, releasing 36% of atRA. 相似文献