低密度PS发泡材料的制备及其性能研究
摘要
聚苯乙烯(PS)是无定形、非极性线性高聚物,具有优良的绝热、绝缘和发泡成型性；CO2在PS中的溶解度较小,并且扩散系数较大,所以制备低密度的PS发泡制品有较大的挑战性。超临界二氧化碳(SC-CO2)具有无污染、化学稳定、低成本等优点,并且临界点(临界温度31.5℃,临界压力7.3MPa)容易获取,已经被应用于工业化生产中。
本文研究了共混PMMA后对PS发泡的影响,讨论温度、压力以及PMMA含量对发泡的影响,并确定了实验工艺区域内获得较好发泡效果的工艺条件。PMMA的加入增加了CO2在体系中的吸附量,并且提高了CO2在其中的稳定性。PS/PMMA体系发泡得到最低表观密度为0.042g／cm3,泡孔直径为11.196μm,泡孔密度最大值为9.23×109个／cm3,其发泡性能优于纯PS体系。
本文还研究了乙醇／CO2复合发泡剂对PS发泡的影响。吸附实验表明：乙醇／CO2复合发泡剂在PS中的溶解度明显高于单纯CO2在PS中的溶解度,能显著降低PS发泡制品的表观密度,所获得发泡样品的表观密度最小为0.042g／cm3。随发泡剂吸附量增大,发泡剂在PS中的扩散系数增大；乙醇含量过大,得到发泡制品收缩严重,且表观密度增大。
本文最后研究了机头结构对PS发泡过程的影响。机头入口角度对PS发泡有较大影响,机头入口角不同时,发泡样品的宽度和厚度也不同。经过实验获得最佳发泡机头入口角为90°。
Polystyrene (PS) are amorphous, non-polar linear polymer with excellent thermal insulation, insulation, and foamability. Solubility of CO2 in the PS is small and with large diffusion coefficient, the density of the PS foam products prepared by a greater challenge. Supercritical carbon dioxide (SC-CO2) has the advantage of clean, chemical stability and low cost, and the critical point (critical temperature 31.5℃, the critical pressure of 7.3MPa) could be obtained easily. SC-CO2 has been used in the industrial production.
We studied the impact of PS foam after blending with PMMA. Discuss the temperature, pressure and the content of PMMA on the foam's impact and to identify the experimental process in the region to obtain better foaming effect of processing conditions. The addition of PMMA increased CO2 absorption capacity in the system, and improve the stability of CO2 in it. PS/PMMA system have the lowest apparent density foam 0.042 g/cm3, the cell diameter 11.196μm, the maximum cell density was 9.23×109/cm3. The foamability of this system is superior to pure PS system.
We also studied ethanol/CO2 blowing agent on the impact of PS foam. Adsorption experiments showed that:ethanol/CO2 blowing agent solubility in the PS was significantly higher than the solubility of CO2. The apparent density of PS foam can significantly reduce, we obtained a minimum apparent density is 0.042g/cm3. With the adsorption capacity of blowing agent increased, the diffusion coefficient of blowing agent in the PS becomes larger. The content of alcohol was too large, the apparent density of PS foam was larger and with serious foam shrinkage.
Finally, we studied the structure of the die impact of the PS foam process. Entrance angle of the die o has great influence n the PS foam. The width and thickness of the foam samples are different with different entrance angle of the die. After the experiment, we obtained the optimal foam with the die angle of 90°.
本文研究了共混PMMA后对PS发泡的影响,讨论温度、压力以及PMMA含量对发泡的影响,并确定了实验工艺区域内获得较好发泡效果的工艺条件。PMMA的加入增加了CO2在体系中的吸附量,并且提高了CO2在其中的稳定性。PS/PMMA体系发泡得到最低表观密度为0.042g／cm3,泡孔直径为11.196μm,泡孔密度最大值为9.23×109个／cm3,其发泡性能优于纯PS体系。
本文还研究了乙醇／CO2复合发泡剂对PS发泡的影响。吸附实验表明：乙醇／CO2复合发泡剂在PS中的溶解度明显高于单纯CO2在PS中的溶解度,能显著降低PS发泡制品的表观密度,所获得发泡样品的表观密度最小为0.042g／cm3。随发泡剂吸附量增大,发泡剂在PS中的扩散系数增大；乙醇含量过大,得到发泡制品收缩严重,且表观密度增大。
本文最后研究了机头结构对PS发泡过程的影响。机头入口角度对PS发泡有较大影响,机头入口角不同时,发泡样品的宽度和厚度也不同。经过实验获得最佳发泡机头入口角为90°。
Polystyrene (PS) are amorphous, non-polar linear polymer with excellent thermal insulation, insulation, and foamability. Solubility of CO2 in the PS is small and with large diffusion coefficient, the density of the PS foam products prepared by a greater challenge. Supercritical carbon dioxide (SC-CO2) has the advantage of clean, chemical stability and low cost, and the critical point (critical temperature 31.5℃, the critical pressure of 7.3MPa) could be obtained easily. SC-CO2 has been used in the industrial production.
We studied the impact of PS foam after blending with PMMA. Discuss the temperature, pressure and the content of PMMA on the foam's impact and to identify the experimental process in the region to obtain better foaming effect of processing conditions. The addition of PMMA increased CO2 absorption capacity in the system, and improve the stability of CO2 in it. PS/PMMA system have the lowest apparent density foam 0.042 g/cm3, the cell diameter 11.196μm, the maximum cell density was 9.23×109/cm3. The foamability of this system is superior to pure PS system.
We also studied ethanol/CO2 blowing agent on the impact of PS foam. Adsorption experiments showed that:ethanol/CO2 blowing agent solubility in the PS was significantly higher than the solubility of CO2. The apparent density of PS foam can significantly reduce, we obtained a minimum apparent density is 0.042g/cm3. With the adsorption capacity of blowing agent increased, the diffusion coefficient of blowing agent in the PS becomes larger. The content of alcohol was too large, the apparent density of PS foam was larger and with serious foam shrinkage.
Finally, we studied the structure of the die impact of the PS foam process. Entrance angle of the die o has great influence n the PS foam. The width and thickness of the foam samples are different with different entrance angle of the die. After the experiment, we obtained the optimal foam with the die angle of 90°.
引文
[1]吴舜英,徐敬一.泡沫塑料成型[M],北京：化学工业出版社,1999：1-9.
[2]陈斌艺、王澜,微孔塑料[J].塑料制造,2008：86-89.
[3]邓小珍,柳和生.微孔(发泡)塑料的制备方法[J].轻工机械,2006.24(2)：16-19.
[4]Seeler K A, Drake B D, Billington S A, et al.Net-shaped Sintered Microcellular Foam Parts [J]. Annual Technical Conference Society of Plastics Engineers,1997,2032-2035.
[5]Collias D I, Baird D G.Tensile Toughness of Microcellular Foams of Polystyrene, Styrene-acrylonitrile Copolymer and Polycarbon-ate and Effect of Dissolved Gas on the Tensile Toughness of the Same Polymer Matrices and Microcellular Foams [J]. Polymer Engineering and Science,1995,35(18):1167-1177.
[6]Ioannis Tsivintzelis, Anastasia G. Angelopoulou, Costas Panayiotou. Foaming of polymers with supercritical CO2:An experimental and theoretical study[J]. Polymer,2007(48): 5928-5939.
[7]M. Sauceau, C. Nikitine, E. Rodier, J. Fages, Effect of supercritical carbon dioxide on polystyrene extrusion[J]. Sciencedirect J. of Supercritical Fluids.2007(43):367-373
[8]张轶楠,马一菲.XPS板在节能建筑中的现状及发展前景[J].辽宁建材,2009(9)：40.
[9]魏和中.聚苯乙烯XPS板与EPS板应用分析[J].化学建材,2008,24(2)：29-30.
[10]黄清.新型的保温材料—挤塑聚苯乙烯保温板的制备[J].甘肃科技,2006(20)：36-38.
[11]吕咏梅.发泡剂的研究现状与发展趋势[J].橡胶科技市场,2010(3)：5-8.
[12]Xiangmin Han, Jiong Shen, Hanxiong Huang, David L. Tomasko, L. James Lee, CO2 Foaming Based on Polystyrene/Poly(methyl methacrylate) Blend and Nanoclay[J]. Polymer Engineering And Science,2007,47(2):103-111.
[13]俞琛捷,马宏佳,周志华.超临界流体技术的应用研究进展[J].化学世界,2007,02：118-120.
[14]Long Yu, Hongsheng Liu, Ling Chen, Thermal Behaviors of Polystyrene Plasticized With Compressed Carbon Dioxide in a Sealed System[J]. Polymer Engineering And Science, 2009,49(9):1800-1805.
[15]S.Doroudiani, H.Omidian. Environmental, health and safety concerns of decorative mouldings made of expanded polystyrene in buildings [J]. Building and Environment, 2009,45(3):1-8.
[16]Wang J, Cheng X G, Zheng X J, Yuan M J, He J S. Preparation and Characterization of Microcellular Polystyrene/Polystyrene Ionomers Blends by Using Supercritical Carbon Dioxide[J]. Polym. Sci. Part B:Polym. Phys.,2003(41):368-377.
[17]李洪春,张广成,顾军渭,陈挺,刘铁民.微孔塑料的成型原理、制备和最新发展[J].工程塑料应用,2006(34)：76-78.
[18]陈国华,彭玉成.国外微孔塑料物理发泡研究现状[J].中国塑料,1998,12(1)：15.
[19]Baldwin D F, Park C B, Suh N P. An Extrusion System for the Processing of Microcellular Polymer Sheets:Shaping and Cell Growth Control [J]. Polym. Eng. Sci.,1996,36(10): 1425-1435.
[20]伍海尉,赵良知.超临界CO2／PS微孔塑料挤出成型中成核数对气泡核自由长大的影响[J].广东化工,2005(4)：15-18.
[21]Deming Mao, Jack R. Edwards, Albert Harvey. Prediction of foam growth and its nucleation in free and limited expansion [J]. Chemical Engineering Science.,2006(61): 1836-1845.
[22]Wu Haiwei, Zhao Liangzhi. Influence of the Nucleation Density on the Bubbles Free Growth in MicroceUular Plastics Extrusion Processing for Supercritical CO2/PS. Guangzhou Chemical,2005(4):16-18.
[23]伍海尉.超临界CO2／PS微孔塑料挤出成型中气泡核自由长大阶段的机理研究[D].华南理工大学硕士学位论文,2005.
[24]吴晓丹,彭玉成,蔡业彬.超临界CO2在聚合物中的溶解度和扩散性研究[J].中国塑料,2005(7)：59-63.
[25]Zhang P, Zhou N Q, Wu Q F, Wang M Y, Peng X F. Microcellular Foaming of PE/PP Blends[J]. Appl. Polym. Sci.,2007(104):4149-4159.
[26]Kimberly F.Ebb,Amyns.Trja. Solubility and diffusion of carbon dioxide in polymers[J]. Fluid Phase Equilibria,1999:1029-1034.
[27]罗卫华,周南桥.PS/PMMA共混体系的挤出流变行为[J].合成树脂及塑料,2007,24(06)：48.
[28]Muratani K, Shimbo M, Miyano Y, Correlation of Deconpression Temperature on the cell Density of Foamed Polystyrene[J]. Cellular Polymer,2005,24(1):15-27.
[29]Krause B,van der Vegt N F A,Wessling M.New way to produce porous polymeric membranes by carbon dioxide foaming[J]. Desalination,2002(144):5-7.
[30]Richard Gendrony, Michel F. Champagne, Foaming Polystyrene with a Mixture of CO2 and Ethanol[J]. Journal of Cellular Plastics,2006,42(2):127-138.
[31]Tetsuo Otsuka, Kentaro Taki, Masahiro Ohshima. Nanocellular Foams of PS/PMMA Polymer Blends [J]. Macromolecular Materials and Engineering,2007,293(1):78-82.
[32]Kentaro Taki, Kouei Nitta, Shin-Ichi Kihara, Masahiro Ohshima. CO2 Foaming of Poly(ethylene glycol)/Polystyrene Blends:Relationship of the Blend Morphology, CO2 Mass Transfer, and Cellular Structure[J]. Journal of Applied Polymer Science,2005,97(5): 1899-1905.
[33]Hao Zhou, Jian Fang, Jichu Yang, Xuming Xie. Effect of the supercritical CO2 on surface structure of PMMA/PS blend thin films[J]. The Journal of Supercritical Fluids,2003, 26(2):137-145.
[34]何亚东.聚合物微发泡材料制备技术理论研究[J].塑料,2004,33(3)：8-14.
[35]XU Xiang. Design of an injection—molding system for manufaeture of microcelluar foams[D]. Toronto:University of Toronto,2002.
[36]江青松,柳合生等.微孔塑料成型及成何喷嘴几何结构的分析[J].轻工机械,2007,25(2)：30-32.
[37]Park C B, Lee P C, Wang J. Strategies for achieving microcellular LDPE foams in extrusion [J]. Cellular Polymers,2006,25 (1):1-18.
[38]Park C B, Suh N P. Filamentary extrusion of microcellular polymers using a rapid decompressive element[J]. Polym Eng Sci,1996,36(1):34-38.
[39]XM Han. Continuous production of microcellular foams [D]. The Ohio State University, 2003.
[40]卢岩,信春玲,李庆春,等.聚合物／超临界流体发泡体系的泡孔生长过程模拟[J].塑料,2009,38(1)：16-18.
[41]LiJun Wang, Girish M. Ganjyal, et.al. Modeling of Bubble Growth Dynamics and Nonisothermal Expansion in Starch-Based Foams During Extrusion [J]. Adv. Polym. Tech.,2005,24(1):29-45.
[42]Park C. B., Suh N. P. Filamentary extrusion of microcellular polymers using a rapid decompressive element [J]. Polym Eng Sci,1996,36(1):34.
[43]Park C B, Baldwin D E, Suh N P. Effect of the pressure drop rate on cell nucleation in continuous processing of microcellular polymers [J]. Polym Eng Sci,1995,35(5):432-440.
[44]Park C B. The Role of Polymer/Gas Solutions in Continuous Processing of Microcellular Polymers [D]. Dept. Mech. Eng., MIT,1993.
[45]詹姆士F.史蒂文森.聚合物成型加工新技术[M].化学工业出版社,2004：85-90.
[46]David L. Tomasko, Adam Burley, Lu Feng, Shu-Kai Yeh, Koki Miyazono, Sharath Nirmal-Kumar, Isamu Kusaka, Kurt Koelling, Development of CO2 for polymer foam applications[J]. The Journal of Supercritical Fluids,2009(47):493-499.
[47]Chen Hao, Zhao Jingzuo, Liu Juan, Guan Rong. Current Situation and Prospect of Foaming Agent for Foamed Plastics [J]. Plastics Science and Technology,2009(37):68-72.
[48]冯西桥.王轶,李志义,胡大鹏,刘学武,张晓冬,夏远景.超临界二氧化碳对聚合物的增塑作用及应用[J].化学工业与工程技术,2004(6)：23-26.
[49]Ruinaard H. Elongational Viscosity As a Tool to Predict the Foanability of Polyolefins[J]. Cell. Plast,2006(42):207-220.
[50]Shimbo M, Baldwin D F, Suh N P. The viscoelastic behavior of microcellular plastics with varying cell size [J]. Polymer Engineering and Science,1995,35(17):1387-1393.
[51]邓小珍,柳和生,黄兴元,赖家美.PS／超临界CO2微孔塑料挤出成型中温度对气泡成核的影响[J].工程塑料应用,2008(36)：34-36.
[52]Hail Xiangmi, Koelling K W, et al. Effect of die temperature on the morphology Of micmcelllllar foams[J]. Polymer Engineering and Science,2003,43(6):1206-1220.
[2]陈斌艺、王澜,微孔塑料[J].塑料制造,2008：86-89.
[3]邓小珍,柳和生.微孔(发泡)塑料的制备方法[J].轻工机械,2006.24(2)：16-19.
[4]Seeler K A, Drake B D, Billington S A, et al.Net-shaped Sintered Microcellular Foam Parts [J]. Annual Technical Conference Society of Plastics Engineers,1997,2032-2035.
[5]Collias D I, Baird D G.Tensile Toughness of Microcellular Foams of Polystyrene, Styrene-acrylonitrile Copolymer and Polycarbon-ate and Effect of Dissolved Gas on the Tensile Toughness of the Same Polymer Matrices and Microcellular Foams [J]. Polymer Engineering and Science,1995,35(18):1167-1177.
[6]Ioannis Tsivintzelis, Anastasia G. Angelopoulou, Costas Panayiotou. Foaming of polymers with supercritical CO2:An experimental and theoretical study[J]. Polymer,2007(48): 5928-5939.
[7]M. Sauceau, C. Nikitine, E. Rodier, J. Fages, Effect of supercritical carbon dioxide on polystyrene extrusion[J]. Sciencedirect J. of Supercritical Fluids.2007(43):367-373
[8]张轶楠,马一菲.XPS板在节能建筑中的现状及发展前景[J].辽宁建材,2009(9)：40.
[9]魏和中.聚苯乙烯XPS板与EPS板应用分析[J].化学建材,2008,24(2)：29-30.
[10]黄清.新型的保温材料—挤塑聚苯乙烯保温板的制备[J].甘肃科技,2006(20)：36-38.
[11]吕咏梅.发泡剂的研究现状与发展趋势[J].橡胶科技市场,2010(3)：5-8.
[12]Xiangmin Han, Jiong Shen, Hanxiong Huang, David L. Tomasko, L. James Lee, CO2 Foaming Based on Polystyrene/Poly(methyl methacrylate) Blend and Nanoclay[J]. Polymer Engineering And Science,2007,47(2):103-111.
[13]俞琛捷,马宏佳,周志华.超临界流体技术的应用研究进展[J].化学世界,2007,02：118-120.
[14]Long Yu, Hongsheng Liu, Ling Chen, Thermal Behaviors of Polystyrene Plasticized With Compressed Carbon Dioxide in a Sealed System[J]. Polymer Engineering And Science, 2009,49(9):1800-1805.
[15]S.Doroudiani, H.Omidian. Environmental, health and safety concerns of decorative mouldings made of expanded polystyrene in buildings [J]. Building and Environment, 2009,45(3):1-8.
[16]Wang J, Cheng X G, Zheng X J, Yuan M J, He J S. Preparation and Characterization of Microcellular Polystyrene/Polystyrene Ionomers Blends by Using Supercritical Carbon Dioxide[J]. Polym. Sci. Part B:Polym. Phys.,2003(41):368-377.
[17]李洪春,张广成,顾军渭,陈挺,刘铁民.微孔塑料的成型原理、制备和最新发展[J].工程塑料应用,2006(34)：76-78.
[18]陈国华,彭玉成.国外微孔塑料物理发泡研究现状[J].中国塑料,1998,12(1)：15.
[19]Baldwin D F, Park C B, Suh N P. An Extrusion System for the Processing of Microcellular Polymer Sheets:Shaping and Cell Growth Control [J]. Polym. Eng. Sci.,1996,36(10): 1425-1435.
[20]伍海尉,赵良知.超临界CO2／PS微孔塑料挤出成型中成核数对气泡核自由长大的影响[J].广东化工,2005(4)：15-18.
[21]Deming Mao, Jack R. Edwards, Albert Harvey. Prediction of foam growth and its nucleation in free and limited expansion [J]. Chemical Engineering Science.,2006(61): 1836-1845.
[22]Wu Haiwei, Zhao Liangzhi. Influence of the Nucleation Density on the Bubbles Free Growth in MicroceUular Plastics Extrusion Processing for Supercritical CO2/PS. Guangzhou Chemical,2005(4):16-18.
[23]伍海尉.超临界CO2／PS微孔塑料挤出成型中气泡核自由长大阶段的机理研究[D].华南理工大学硕士学位论文,2005.
[24]吴晓丹,彭玉成,蔡业彬.超临界CO2在聚合物中的溶解度和扩散性研究[J].中国塑料,2005(7)：59-63.
[25]Zhang P, Zhou N Q, Wu Q F, Wang M Y, Peng X F. Microcellular Foaming of PE/PP Blends[J]. Appl. Polym. Sci.,2007(104):4149-4159.
[26]Kimberly F.Ebb,Amyns.Trja. Solubility and diffusion of carbon dioxide in polymers[J]. Fluid Phase Equilibria,1999:1029-1034.
[27]罗卫华,周南桥.PS/PMMA共混体系的挤出流变行为[J].合成树脂及塑料,2007,24(06)：48.
[28]Muratani K, Shimbo M, Miyano Y, Correlation of Deconpression Temperature on the cell Density of Foamed Polystyrene[J]. Cellular Polymer,2005,24(1):15-27.
[29]Krause B,van der Vegt N F A,Wessling M.New way to produce porous polymeric membranes by carbon dioxide foaming[J]. Desalination,2002(144):5-7.
[30]Richard Gendrony, Michel F. Champagne, Foaming Polystyrene with a Mixture of CO2 and Ethanol[J]. Journal of Cellular Plastics,2006,42(2):127-138.
[31]Tetsuo Otsuka, Kentaro Taki, Masahiro Ohshima. Nanocellular Foams of PS/PMMA Polymer Blends [J]. Macromolecular Materials and Engineering,2007,293(1):78-82.
[32]Kentaro Taki, Kouei Nitta, Shin-Ichi Kihara, Masahiro Ohshima. CO2 Foaming of Poly(ethylene glycol)/Polystyrene Blends:Relationship of the Blend Morphology, CO2 Mass Transfer, and Cellular Structure[J]. Journal of Applied Polymer Science,2005,97(5): 1899-1905.
[33]Hao Zhou, Jian Fang, Jichu Yang, Xuming Xie. Effect of the supercritical CO2 on surface structure of PMMA/PS blend thin films[J]. The Journal of Supercritical Fluids,2003, 26(2):137-145.
[34]何亚东.聚合物微发泡材料制备技术理论研究[J].塑料,2004,33(3)：8-14.
[35]XU Xiang. Design of an injection—molding system for manufaeture of microcelluar foams[D]. Toronto:University of Toronto,2002.
[36]江青松,柳合生等.微孔塑料成型及成何喷嘴几何结构的分析[J].轻工机械,2007,25(2)：30-32.
[37]Park C B, Lee P C, Wang J. Strategies for achieving microcellular LDPE foams in extrusion [J]. Cellular Polymers,2006,25 (1):1-18.
[38]Park C B, Suh N P. Filamentary extrusion of microcellular polymers using a rapid decompressive element[J]. Polym Eng Sci,1996,36(1):34-38.
[39]XM Han. Continuous production of microcellular foams [D]. The Ohio State University, 2003.
[40]卢岩,信春玲,李庆春,等.聚合物／超临界流体发泡体系的泡孔生长过程模拟[J].塑料,2009,38(1)：16-18.
[41]LiJun Wang, Girish M. Ganjyal, et.al. Modeling of Bubble Growth Dynamics and Nonisothermal Expansion in Starch-Based Foams During Extrusion [J]. Adv. Polym. Tech.,2005,24(1):29-45.
[42]Park C. B., Suh N. P. Filamentary extrusion of microcellular polymers using a rapid decompressive element [J]. Polym Eng Sci,1996,36(1):34.
[43]Park C B, Baldwin D E, Suh N P. Effect of the pressure drop rate on cell nucleation in continuous processing of microcellular polymers [J]. Polym Eng Sci,1995,35(5):432-440.
[44]Park C B. The Role of Polymer/Gas Solutions in Continuous Processing of Microcellular Polymers [D]. Dept. Mech. Eng., MIT,1993.
[45]詹姆士F.史蒂文森.聚合物成型加工新技术[M].化学工业出版社,2004：85-90.
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