摘要
聚对苯二甲酸乙二酯(PET)主要用于纤维生产,而在非纤维领域的应用则主要是制造食品、饮料的包装容器及薄膜。由于PET具有高强度、高刚性、良好的耐热性及尺寸稳定性等综合性能,PET瓶的生产近年来得到很大的发展,由此也带来了废弃PET瓶产生的环境污染。因此,回收利用废弃PET不但可以减少环境污染,而且可以降低生产成本,节省资源。此外,PET纤维属于熔融性可燃纤维,燃烧时容易形成熔滴,熔滴容易带来包括烫伤等在内的二次伤害,因此需要对PET纤维进行抗熔滴改性。
本文首先对瓶片PET和纤维级PET的流变性能进行了对比研究,然后在回收PET瓶片(rPET)基体中添加一种抗熔滴树脂进行共混,研究了rPET/抗熔滴树脂共混熔体的流变性能,最后制备了rPET/抗熔滴树脂共混纤维,将共混纤维进行后处理,共混纤维内部的硅树脂水解交联生成三维网状的热固性树脂,燃烧时该树脂对涤纶熔滴起到包覆、加速炭化并增加成炭量的作用,以达到抗熔滴的目的。本文通过熔体流动速率仪和RH7双柱型毛细管流变仪、SEM、FTIR、XRD、TG、DSC、KES-G1万能试验机以及抗熔滴测试等手段研究了共混熔体的流变性能、共混纤维及抗熔滴纤维的性能,主要研究内容和结论如下:
(1)利用RH7双柱型毛细管流变仪对PET瓶片与纺丝级PET熔体的流变性能进行了对比研究。讨论剪切速率和温度对表观粘度、非牛顿指数、结构粘度指数及粘流活化能的影响。结果表明:两种熔体都属于非牛顿假塑性流体,表观粘度都随着剪切速率和温度的增加而降低;在相同的温度下,瓶片PET熔体的非牛顿指数比纺丝级PET熔体的小,而结构粘度指数则比后者大;两种熔体的粘流活化能均随剪切速率的增大而减小。
(2)采用熔体流动速率仪和RH7双柱型毛细管流变仪对rPET、rPET/抗熔滴共混物熔体进行了流变性能的测试,结果表明:共混物的熔融指数随着抗熔滴树脂含量的增加而增大;表观粘度随着温度的升高和剪切速率的增加逐渐减小,熔体表现假塑性流体的特性;非牛顿指数n随着温度升高而逐渐增大;结构粘度指数随着温度的升高而逐渐降低。粘流活化能随剪切速率的增加而减小。在研究范围内,随着抗熔滴树脂含量的增加,共混物熔体的非牛顿指数越大,结构粘度指数、零切粘度和粘流活化能越小。
(3)SEM、XRD等研究表明,与纯rPET纤维相比,共混纤维的表面较粗糙,并且纤维的结晶结构并没有随着抗熔滴树脂的加入而发生变化,当抗熔滴树脂含量为5%时,共混纤维的结晶度下降到27.18%;万能试验机的结果显示,抗熔滴rPET纤维的断裂强度为134.49Mpa,低于纯rPET纤维的断裂强度。TG、DSC、抗熔滴性能等测试表明,随着抗熔滴树脂含量的增加,共混纤维的熔点和最大热分解速率逐渐变小,单位时间(1min)内熔滴数量减少,共混纤维的成炭量逐渐增加,抗熔滴性能逐渐增强。
Besides fiber production, polyethylene terephthalate (PET) is applied in food, beverages containers and packaging films manufacturing in large quantity. The reuse and recycling of bottle grade PET is of great importance in terms of environmental protection and resources saving. In addition, polyester fibers are thermoplastic and flammable, when burning they tend to form molten drops, which can bring burns and other secondary damages, so the modification of polyester fibers is necessary to improve the performance of anti-dripping.
In this paper, the rheological properties of bottle (rPET) and fiber grade polyester were analyzed and compared, then an anti-dripping resin was added to rPET resin and the rheological properties of melt blends were studied. At last, the rPET/anti-dripping resin blended fibers were prepared. The thermoplastic anti-dripping copolymer in polyester fiber will hydrolyze and crosslink into a three-dimensional thermosetting network after putting blended fibers in the water. The thermosetting anti-dripping resin can warp the melting drops and then accelerate charring, and thus the anti-dripping effect was achieved. The melt rheological properties of blends, performance of the blending fiber and anti-dripping fiber were studied by means of melt flow rate indexer, double capillary rheometer RH 7D, SEM, FTIR, XRD, TG, DSC, KES-G1 MULTI-PURPOSE TENSILE TESTER and anti-dropping tests.
The main research contents and conclusions are listed as follows:
(1) The melt rheological properties of bottle and fiber grade polyester were comparatively studied by double capillary rheometer RH 7D. The influence of shear rate and temperature on the apparent viscosity, non-Newtonian index, structural viscosity index, and activation energy for viscous flow were discussed. The results show that the two kinds of melt belong to non-Newtonian pseudoplastic fluid and the apparent viscosity decreases with the increasing of shear rate and temperature. At the same temperature, the non-Newtonian index of bottle grade melt is smaller than that of fiber grade polyester, but the structural viscosity index is larger than fiber grade polyester. The activation energy for viscous flow of two kinds of melt decreases with the increasing of shear rate.
(2) The melt rheological properties of rPET and blends of rPET/anti-dripping resin were studied by melt flow rate indexer and double capillary rheometer RH 7D. The results show that the melt index of rPET/anti-dripping resin blends increased along with increasing of the anti-dripping resin content; the apparent viscosity gradually decreased with raising temperature and shear rate, their melts showed non-Newtonian pseudoplastic fluid characteristics; the non-Newton index gradually increased with the increasing of temperature; the structural viscosity index decreases with the increasing of temperature. The activation energy for viscous flow of melt decreases with the increasing of shear rate. Within the framework of the study, with the increase of anti-dripping resin content, non-Newton index of rPET/anti-dripping resin blends melt increased, the structural viscosity index, zero shear viscosity and the activation energy of viscosity flow reduced.
(3) SEM, XRD results showed that the blending fibers' surface was rough compared with the traditional pure rPET fibers, and the crystal structure of blending fibers was unchanged with the addition of anti-dripping resin. The crystallinity decreased to 26% when the ratio of anti-dripping resin was 27.18%. The results of KES-G1 showed that the fracture intensity of anti-dripping polyester fibers was 134.49Mpa that was lower than pure polyester fibers'. TG, DSC and the anti-dripping performance test indicated that the melting point, the maximum thermal decomposition rate of the blending fibers and the number of drops of the anti-dripping fibers in unit time (1min) were decreased with the increase of anti-dripping resin content. The char residue of blending fibers was increased and the anti-dripping effect got gradually strengthened when raised the content of anti-dripping resin.
引文
[1]张师民.聚酯的生产及应用[M].北京:中国石化出版社, 1997:295-296.
[2]杜鹏,何继敏. PET啤酒瓶阻隔技术的研究进展与发展前景.工程塑料应用. 2006, 34(7): 71-74.
[3]田心平,王澜. PET回收再生技术及应用[J].塑料制造, 2007(6): 65-71.
[4]来可华,陈鹰,肖海燕.浅谈我国再生PET短纤维工业的发展历程和前景[J].合成纤维, 2010, 39(2): 1-5.
[5]林世东,谭亦武.发达国家再生PET行业发展现状和进展[J].合成纤维, 2009, 38(1): 1-5.
[6]冷纯延,袁成侠.瓶片聚酯纺再生短纤维技术[J].产业用纺织品, 1996, 14(2): 28-30.
[7]潘婉莲,胡盼盼,刘兆峰等.用瓶片聚酯回收料试纺涤纶长丝[J].合成纤维工业, 2002, 25(3): 58-59.
[8]何威,段小虎,张守运.回收聚酯瓶片在普通纺丝设备上纺制再生长丝的技术探讨[J].合成纤维, 2010(5): 32-34.
[9]查安霞.回收聚酯瓶片料纺制油毡布基布用涤纶短纤维的生产工艺[J].合成纤维, 2009(9): 34-36.
[10]沈明华.用聚酯瓶片料和再生料生产中空粗旦短纤维[J].合成纤维, 1996, 26(6): 40-42.
[11]黄婉娟.利用回收聚酯纺制阻燃短纤维的工艺探讨[J].合成纤维, 1998, 27(4): 52-54.
[12]马辉,崔丽华,栾宇等.用TiO2/ZnO超细粉体改性的PET流变性研究[J]. PET工业,2009, 22(3): 15-17.
[13]戚嵘嵘,周宇,周持兴.回收PET/PA66复合材料的研究[J].工程塑料应用, 2006, 34(10): 4-6.
[14]陈克宇,张立文,史华.回收PET瓶增韧改性的研究[J].现代塑料加工应用, 1992(6): 19-21.
[15] Antonio F. Avila and Marcos V, Duarte. A mechanical analysis on recycled PET/HDPE composites [J], Polymer Degradation and Stability, 2003, 80(2): 373-382.
[16] Jazani O M, Azar A. Blends of PET bottle waste with modified styrene butadiene rubber through reactive mixing. J Appl Polym Sci, 2006, 102: 1615-1623.
[17] K. Friedrich, M, Evstatiev, S. Fakirov et al, Microfibrillar reinforced composites from PET/PP blends: processing, morphology and mechanical properties[J], Composites Science and Technology, 2005, 65: 107-116.
[18]郝源增,桑杰,刘文志等. PET瓶回收料的增粘工艺研究[J].工程塑料应用, 2005, 35(7): 26-28.
[19]蔡长庚,唐峰,贾德民. 2, 2-双(2-噁唑啉)与苯酐联用改性回收PET的动态热性能研究[J].塑料,2005, 34(2): 63-66.
[20]唐峰,蔡长庚,贾德民. 2, 2-双(2-噁唑啉)改性回收PET的研究[J].中国塑料, 2004, 18(1): 81-84.
[21] Firas Awaja, Fugen Daver, Recycled poly(ethylene terephthalate) Chain Extension by A Reative Extrusion Process[J], Polymer Engeering and Science, 2004, 44(8):1579-1587.
[22] L. Incarnato, P. Scarfato, L. Di Maio et al, Structure and rheology of recycled PET modified by reactive extrusion[J], Polymer, 2000, 48(18): 6825-6831.
[23] N.Torres, J J Roben, B Boutevin, chemical Modification of Virgin and Recycled poly(ethylene terephthalate) by adding of Chain Extenders during Processing[J], Journal of Applied Polymer Science, 2001, 79: 1816-1824.
[24] Geroge P. Karayannidis, Eleni A. Psalida, Chain Extension of Recycled poly(ethylene terephthalate) with 2,2’-(1,4-phenylene) bis (2-oxiazoline)V, Journal of Applied Polymer Science, 2000, 77: 2206-2211.
[25] Firas Awaja and Dumitru Pavel, Recycling of PET[J]. European Polymer Journal, 2005, 41(7): 1453-1477.
[26] TANG Xian-wen, GUO Wei-hong, GAO Yuan-ji, et al, Preparation of Novel Super-tough Ploy(ethylene terephthalate) Engineering Plastic[J],中山大学学报, 2005, 44(2): 39-41. [ 27 ] Karayannidis GP, Kokkalas DE, Bikiaris DN, Solid-state polycondensation of Ploy(ethylene terephthalate) recycled from postconsumer soft-drink bottlesⅡ[J], J Appl Polym Sci, 1995, 56: 405-410.
[28] Karayannidis GP, Kokkalas D, Bikiaris D, Solid-state polycondensation of Ploy(ethylene terephthalate) recycled from postconsumer soft-drink bottlesⅠ[J], J Appl Polym Sci, 1993, 50: 2135-2142.
[29]唐琦琦,付强,杨斌.固相挤出回收PET结晶性能和降解程度的研究[J].中国塑料, 2005, 19(8): 84-88.
[30] A. L. F. de M. Giraldi, J. R. Bartoli, J. I. Velasco et al, Mei. Glass fiber recycled poly(ethylene terephthalate) composites: mechanical and thermal properties[J], Polymer Testing, 2005, 24(4):507-512.
[31] Alessandro Pegoretti, Amabile Penati, Recycled poly(ethylene terephthalate) and its short glass fibers composites: effects of hygrothermal aging on the thermo-mechanical behaviour[J], Polymer, 2004, 45: 7995-8004.
[32]周晓安,龙泽君,赵东.增强改性回收PET材料的研制[J].塑料加工, 1999, 27(4): 33-35.
[33]郝源增,梁文聪,刘文志等.回收PET玻纤复合材料的结晶性能研究[J].塑料工业, 2006, 34(2):42-44.
[34]杜红丽,赵书林,王荣荣.阻燃纤维及其最新研究进展[J].陕西纺织, 2006, 2: 40-42.
[35] Stuart Elton. Reduction of the thermoplastic melt hazard of polyester fabric through the application of a radiation cross-linking technique[J]. Fire and Materials, 1998, 22(1): 19-23.
[36]王建祺等.无卤阻燃聚合物基础与应用[M].北京:科学出版社, 2005.
[37]张强,黄年华.新型有机磷酸酯对涤纶织物的阻燃和抗熔滴研究阻燃纤维及其最新研究进展[J].武汉科技学院学报, 2007, 20(2): 29-32.
[38]邹振高,王西亭,施楣梧.常规阻燃纤维的技术现状与发展趋势[J].纺织导报,2006,3: 45-48.
[39]张军,纪奎江,夏延致.聚合物燃烧与阻燃技术[M].北京,化学工业出版社, 2004.
[40]钱诚,贵大勇,田军等.抗滴落阻燃聚丙烯动态粘弹性能及其纺丝温度研究[J].合成纤维工业, 2006, 29(6): 9-11.
[41]刘渊,王琪.三聚氰胺氰尿酸阻燃尼龙6的抗熔滴燃烧性研究术[J].工程塑料应用, 2005, 33(11): 48-50.
[42] Xiangyang Hao, Guosheng Gai, Jiping Liu, et al. Flame retardancy and anti-dripping effect of OMT/PA nanocomposites[J]. Materials Chemistry and Physics, 2006, 96(1): 34-41.
[43]济南“阻燃耐熔滴聚酯纳米复合材料”项目入围“863”计划[J].新材料产业, 2003, 9:77.
[44]高新方.阻燃纤维新发展[J].新纺织, 2003, 11: 21-23.
[45]王永强,夏延致等.阻燃材料及其应用技术[M].北京:化学工业出版社, 2002.
[46]葛欣国,吴博,王玉忠.主链含磷阻燃共聚酯的合成与性能研究[J].四川大学学报(自然科学版), 2005, 42(1): 139-142.
[47] Da-Ming Ban, Yu-Zhong Wang, Bing Yang, et al. A novel non-dripping algometric flame retardant for polyethylene terephthalate[J]. European Polymer Journal, 2004,40: 1909–1913.
[48] Guoxia Fei, Yuan Liu, Qi Wang. Synergistic effects of novolac-based char former with magnesium hydroxide inflameretardant polyamide-6[J]. Polymer Degradation and Stability, 2008, 93: 1351–1356.
[49]田素峰,王乐军,马君志.阻燃抗熔融粘胶纤维Anti—fcell[J].纺织导报, 2006(12): 42-46.
[50] Mark W. Beach, Nelson G. Rondan, Robert D. Froese, Bruce B. Gerhart, et al. Studies of degradation enhancement of polystyrene by flame retardant additives[J]. Polymer Degradation and Stability, 2008, 93: 1664–1673.
[51] Xin-Guo Ge, De-Yi Wang, Yu-Zhong Wang, et al. A novel phosphorus-containingcopolyester/montmorillonite nanocomposites with improved flame retardancy[J]. European Polymer Journal, 2007, 43: 2882–2890.
[52]曲铭海,葛欣国,王玉忠等.侧基含磷阻燃共PET/BaSO4纳米复合材料的合成与性能研究[J].四川大学学报(自然科学版), 2006, 43(2): 408–413.
[53] De-Yi Wang, Xue-Qi Liu, Yu-Zhong Wang, et al. Preparation and characterization of a novel fire retardant PET/a-zirconium phosphate nano-composite[J]. Polymer Degradation and Stability, 2009, 94: 544–549.
[54] Lijun Qian, Junge Zhi, Bin Tong, et al. Synthesis and characterization of main-chain liquid crystalline copolyesters containing phosphaphenanthrene side-groups[J]. Polymer, 2009, 50: 4813–4820.
[55] Mustapha El Gouri, Abderrahim El Bachiri, Salah Eddine Hegazi, et al. Thermal degradation of a reactive flame retardant basedon cyclotriphosphazene and its blend with DGEBA epoxy resin[J]. Polymer Degradation and Stability, 2009, 94: 2101–2106.
[56] Dan-Qi Chen, Yu-Zhong Wang, Xiao-Ping Hu, et al. Flame-retardant and anti-dripping effects of a novel char-forming flame retardant for the treatment of poly(ethylene terephthalate) fabrics[J]. Polymer Degradation and Stability, 2005, 88(2): 349-356.
[57]张强,黄年华.新型有机磷酸酯对涤纶织物的阻燃和抗熔滴研究阻燃纤维及其最新研究进展[J].武汉科技学院学报, 2007, 20(2): 29-32.
[58]李海东,程凤梅,冼远芳等. PET短纤维辐射接枝改性[J].吉林工学学报, 1999, 20(1): 71-72.
[59]林金平.碳酸饮料瓶用PET结构与性能的研究[D].厦门:厦门大学, 2008: 3-4.
[60]张国耀,徐翔,金剑等.阳离子可染聚酯的流变性能的研究[J].合成纤维, 1999, 28(5): 7-11.
[61]何曼君,陈维孝,董西侠.高分子物理[M].上海:复旦大学出版社, 1990: 261-293.
[62]杨涛锋,李瑶君.氨纶纺丝熔体的流变行为[J].弹性体, 2002, 12(5): 37-39.
[63]董纪震,罗鸿烈,王庆瑞等.合成纤维生产工艺学[M].北京:纺织工业出版社, 1994: 84-89.
[64]沈新元.高分子材料加工原理[M].北京:中国纺织出版社, 2000.
[65]吴大成等.合成纤维熔体纺丝[M].北京:纺织工业出版社, 1980, 230.
[66] A.谢皮斯基.纤维成型基本原理[M].上海:上海科学技术出版社, 1983, 14.
[67] S. G. Wiersehke. The Materials Science and Engineering of Rigid Rod Polymers[J]. MRS. SymP. Proe, 1989, 313: 134.
[68]姜刚.三聚氰胺纤维纺丝原液的制备[D].南京:南京理工大学, 2002.
[69]张耀光,许晓晶等.熔体流动速率仪的发展及应用[J].工程塑料应用, 2007,35(5): 67-68.
[70]金日光,华幼卿.高分子物理[M].第2版.北京:化学工业出版社, 2000.
[71]王全华,付中玉.熔融指数对聚丙烯熔体流动性及纤维强度的影响[J].北京服装学院学报, 2004, 24(4): 27-31.
[72]王莲英,李玲等.透明尼龙熔体流变性能的研究[J].华北工学院学报, 2005,26(4):289-291.
[73] Billmeye, F. M. Jr. Textbook of polymer science[M]. Willy: New York, 1971, 84.
[74]董纪震,罗鸿烈.合成纤维生产工艺学(上册)[M].北京:纺织工业出版社, 1993, 93 - 112.
[75]李明星,王凯.高强高模聚乙烯醇(PVA)纤维的研究进展[J].合成纤维, 2003, 1: 21.
[76]倪如青等.芳砜纶纺丝溶液的流变性能研究[J].合成纤维, 2005, 6.
[77]应宗荣.水溶性聚酯浓溶液的流变特性[J].高分子学报, 2000, 4: 448-451.
[78]林云周等.胶原蛋白/聚乙烯醇共混纺丝原液的流变性能[J].皮革科学与工程, 2006,16(2): 8-13.
[79]杨涛锋,李瑶君等.氨纶纺丝熔体的流变行为[J].弹性体, 2002, 12(5): 37-39.
[80]刘伯林.易染共混PET纤维的研制[D].四川:四川大学, 2002.