This work aimed at effectively utilizing the chemically depolymerized waste poly(ethylene terephthalate)(PET) fibers into useful products for the textile industry.PET fibers were glycolytically degraded by excess ...This work aimed at effectively utilizing the chemically depolymerized waste poly(ethylene terephthalate)(PET) fibers into useful products for the textile industry.PET fibers were glycolytically degraded by excess ethylene glycol as depolymerizing agent and zinc acetate dihydrate as catalyst.The glycolysis product,bis(2-hydroxyethyl) terephthalate(BHET),was purified through repeated crystallization to get an average yield above 80%.Then,BHET was nitrated,reduced,and azotized to get diazonium salt.Finally,the produced diazonium salt was coupled with 1-(4-sulfophenyl)-3-methyl-5-pyrazolone to get azo dyestuff.The structures of BHET and azo dyestuff were identified by FT1 R and ^1H NMR spectra and elemental analysis.Nylon filaments dyed by the synthesized azo dyestuff with the dye bath pH from 4.14 to 5.88 showed bright yellow color.The performances of the dyestuff were described with dye uptake,color fastness,K/S,L^*,a^*,b^*.and △E^* values.展开更多
以经过致密化处理的废旧涤棉军装(废旧涤棉)为原料,以乙二醇(EG)为醇解剂,通过改变EG与废旧涤棉的配比、醇解时间、醇解液循环使用次数等研究了废旧涤棉的醇解效率,以及不同循环次数对醇解产物对苯二甲酸乙二醇酯(BHET)和涤棉织...以经过致密化处理的废旧涤棉军装(废旧涤棉)为原料,以乙二醇(EG)为醇解剂,通过改变EG与废旧涤棉的配比、醇解时间、醇解液循环使用次数等研究了废旧涤棉的醇解效率,以及不同循环次数对醇解产物对苯二甲酸乙二醇酯(BHET)和涤棉织物中的棉纱性能的影响。结果表明:在废旧涤棉与EG质量比为1∶(10~12),废旧涤棉与Na2CO3质量比为1∶0.003,反应温度196℃,反应时间1 h的醇解条件下,醇解液可以循环使用,最佳循环使用次数为4,醇解后产物绝大部分仍为BHET单体,醇解物产率高于60%;醇解后棉纱表面虽有一定程度破坏,但其断裂强度最高仍达1.76 c N/dtex,满足开松再纺纱的要求,可实现棉纱的二次回收利用。展开更多
以草酸盐为前驱体,采用共沉淀法制备CaO/MgO复合固体碱催化剂,将其用于乙二醇(EG)介质中催化降解聚对苯二甲酸乙二酯(PET)。采用X射线衍射、扫描电子显微镜、CO_2程序升温脱附对固体碱催化剂进行表征,分别考察反应温度、反应时间、催化...以草酸盐为前驱体,采用共沉淀法制备CaO/MgO复合固体碱催化剂,将其用于乙二醇(EG)介质中催化降解聚对苯二甲酸乙二酯(PET)。采用X射线衍射、扫描电子显微镜、CO_2程序升温脱附对固体碱催化剂进行表征,分别考察反应温度、反应时间、催化剂用量、EG与PET的质量比对降解产物收率的影响。结果表明,钙镁比为1∶3时,复合固体碱催化剂碱性最强并且形貌规整;催化降解反应温度180℃,反应时间5 h,催化剂用量为2.5%(以PET质量计),EG与PET用量比为25 m L/5 g时催化效果最佳,降解产物最大收率为85.5%。红外光谱、核磁共振氢谱分析表明PET降解产物是对苯二甲酸二乙二醇酯。展开更多
Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate (BHET) were successfully synthesized and characterized by fourier transform infrared spectroscopy (FT-IR). These two k...Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate (BHET) were successfully synthesized and characterized by fourier transform infrared spectroscopy (FT-IR). These two kinds of salts were used to intercalate Na-MMT to yield two kinds of respective organo-modified MMTs. Basal spacing and thermal stability were investigated by using X-ray diffraction (XRD) and thermogravimetric analysis (TGA), respectively. The experimental results show that, as compared with Na-MMT, basal spacings of both of MMTs modified by the quaternary phosphonium salt of BHET (BHETPP) and the quaternary ammonium salt of BHET (BHEA), increase from 12.4 A to 19.7/k and 31.3 A, respec-tively. Thermal stability of BHETPP-modified MMT is much better than that of BHEA-modified MMT, i e, T otof BHETPP-modified MMT is around 400℃ while Tcmset of BHEA-modified MMT is near 250℃. Therefore, with en-larged basal spacing and excellent thermal stability, BHETPP-modified MMT is a promising organo-modified MMT which may be used to prepare polyethylene terephthalate/MMT nanocomposite with high thermal and mechanical performance.展开更多
基金financially supported by the National High-tech R&D Program of China(863 Program,No.2012AA030313)the Open Project Program of Key Laboratory of Eco-Textiles(Jiangnan University),Ministry of Education,China(No.KLET1115)+1 种基金the Fundamental Research Funds for the Central Universities(No. JUSRP11201)the Cooperative Innovation Fund-Prospective Project of Jiangsu Province,China(No.BY2012060)
文摘This work aimed at effectively utilizing the chemically depolymerized waste poly(ethylene terephthalate)(PET) fibers into useful products for the textile industry.PET fibers were glycolytically degraded by excess ethylene glycol as depolymerizing agent and zinc acetate dihydrate as catalyst.The glycolysis product,bis(2-hydroxyethyl) terephthalate(BHET),was purified through repeated crystallization to get an average yield above 80%.Then,BHET was nitrated,reduced,and azotized to get diazonium salt.Finally,the produced diazonium salt was coupled with 1-(4-sulfophenyl)-3-methyl-5-pyrazolone to get azo dyestuff.The structures of BHET and azo dyestuff were identified by FT1 R and ^1H NMR spectra and elemental analysis.Nylon filaments dyed by the synthesized azo dyestuff with the dye bath pH from 4.14 to 5.88 showed bright yellow color.The performances of the dyestuff were described with dye uptake,color fastness,K/S,L^*,a^*,b^*.and △E^* values.
文摘以经过致密化处理的废旧涤棉军装(废旧涤棉)为原料,以乙二醇(EG)为醇解剂,通过改变EG与废旧涤棉的配比、醇解时间、醇解液循环使用次数等研究了废旧涤棉的醇解效率,以及不同循环次数对醇解产物对苯二甲酸乙二醇酯(BHET)和涤棉织物中的棉纱性能的影响。结果表明:在废旧涤棉与EG质量比为1∶(10~12),废旧涤棉与Na2CO3质量比为1∶0.003,反应温度196℃,反应时间1 h的醇解条件下,醇解液可以循环使用,最佳循环使用次数为4,醇解后产物绝大部分仍为BHET单体,醇解物产率高于60%;醇解后棉纱表面虽有一定程度破坏,但其断裂强度最高仍达1.76 c N/dtex,满足开松再纺纱的要求,可实现棉纱的二次回收利用。
文摘以草酸盐为前驱体,采用共沉淀法制备CaO/MgO复合固体碱催化剂,将其用于乙二醇(EG)介质中催化降解聚对苯二甲酸乙二酯(PET)。采用X射线衍射、扫描电子显微镜、CO_2程序升温脱附对固体碱催化剂进行表征,分别考察反应温度、反应时间、催化剂用量、EG与PET的质量比对降解产物收率的影响。结果表明,钙镁比为1∶3时,复合固体碱催化剂碱性最强并且形貌规整;催化降解反应温度180℃,反应时间5 h,催化剂用量为2.5%(以PET质量计),EG与PET用量比为25 m L/5 g时催化效果最佳,降解产物最大收率为85.5%。红外光谱、核磁共振氢谱分析表明PET降解产物是对苯二甲酸二乙二醇酯。
文摘Both of quaternary ammonium and quaternary phosphonium salts of bis-hydroxyethyl terephthalate (BHET) were successfully synthesized and characterized by fourier transform infrared spectroscopy (FT-IR). These two kinds of salts were used to intercalate Na-MMT to yield two kinds of respective organo-modified MMTs. Basal spacing and thermal stability were investigated by using X-ray diffraction (XRD) and thermogravimetric analysis (TGA), respectively. The experimental results show that, as compared with Na-MMT, basal spacings of both of MMTs modified by the quaternary phosphonium salt of BHET (BHETPP) and the quaternary ammonium salt of BHET (BHEA), increase from 12.4 A to 19.7/k and 31.3 A, respec-tively. Thermal stability of BHETPP-modified MMT is much better than that of BHEA-modified MMT, i e, T otof BHETPP-modified MMT is around 400℃ while Tcmset of BHEA-modified MMT is near 250℃. Therefore, with en-larged basal spacing and excellent thermal stability, BHETPP-modified MMT is a promising organo-modified MMT which may be used to prepare polyethylene terephthalate/MMT nanocomposite with high thermal and mechanical performance.