Nano-ZnO particle (nZnOp) reinforced polyethylene glycol (PEG)/polyethylene terephthalate (PET) (nZnOp/PEG/PET) copolymeric composites with different mass fractions and molecular weights of PEG are synthesized...Nano-ZnO particle (nZnOp) reinforced polyethylene glycol (PEG)/polyethylene terephthalate (PET) (nZnOp/PEG/PET) copolymeric composites with different mass fractions and molecular weights of PEG are synthesized via in-situ polymerization. The dispersion of nZnOp in copolymer matrixes and the effects of PEG and nZnOp particles on the crystallization behavior of the composites are studied by TEM, differential scanning calorimetry(DSC), XRD and Fourier thansform infrared spectroscopy (FTIR ). The results reveal that nZnOp particles are dispersed in the matrixes with nano-scale, and the addition of PEG induces more homogeneous dispersion of nZnOp. Simultaneously, these nanoparticles become nucleating centers during the crystallization of the matrixes. PEG segments can improve the flexibility of the PET molecular chain, resulting in the drop of the cold crystallization temperature and the rise of the crystallization rate of the composites. Furthermore, PEG (4 000) with the mass fraction of 10% can promote the crystallization rate of the composites. The mechanical properties show that the nano-particles strengthen and toughen the PET matrix, whereas PEG weakens these improve- ments.展开更多
Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is ...Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is an excellent green chemical process without poisonous substance. Various alkali metals were used as the catalysts. The results showed alkali metals had catalytic activity in a certain extent. The effect of reaction condition was also studied. When the reaction was carded out under the following conditions: the reaction temperature 250℃, molar ratio of EC to DMT 3 : 1, reaction time 3h, and catalyst amount 0.004 (molar ratio to DMT), the yield of DMC was 68.9%.展开更多
In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBT...In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBTNW under alkylpolyglycoside (APG) inducing. The product is thoroughly characterized with the Fourier transform infrared spectroscopy (FrIR), the electron spectroscopy for chemical analysis (ESCA), the thermogravimetric (TG) and the scanning electron microscopy (SEM). It is found that chitosan is successfully grafted onto PBTNW. In addition, the water contact angles, hemolysis tests and cytotoxicity evaluation tests show an improvement in wettability and biocompatihility as a result of graft copolymerization of chitosan. So the CS-grafted PBTNW exhibits greater superiority than the original PBTNW. The CS-grafted PBTNW can be a candidate for blood filter materials and other medical applications.展开更多
Nonisothermal crystallization behavior of poly(butylene adipate-co-terephthalate)(PBAT) synthesized via direct esterification and polycondensation reactions was investigated by the differential scanning calorimetry(DS...Nonisothermal crystallization behavior of poly(butylene adipate-co-terephthalate)(PBAT) synthesized via direct esterification and polycondensation reactions was investigated by the differential scanning calorimetry(DSC).The Avrami equation modified by Jeziorny and the Z.S.Mo equation were employed to describe the non-isothermal crystallization kinetics of copolyester samples.The test results showed that the Avrami equation was successful in describing nonisothermal crystallization process of PBAT copolyesters.PBAT copolyester could give birth to secondary crystallization.The crystallization parameter(Zc) increased with an increasing cooling rate and the Avrami exponent(n) was around 2.3.For a given cooling rate,the value of Zc demonstrated a sagging trend with an increase in adipic acid(AA) content.The equation proposed by Z.S.Mo was successful in describing the nonisothermal crystallization kinetics of PBAT copolyesters.展开更多
In this paper, poly(butylene-terephthalate)-layered silicate of clay nanocomposites (NPBT) are reported. Their thermal properties, heat distortion temperature (HDT) and crystallization nucleation are investigated. NPB...In this paper, poly(butylene-terephthalate)-layered silicate of clay nanocomposites (NPBT) are reported. Their thermal properties, heat distortion temperature (HDT) and crystallization nucleation are investigated. NPBT samples have apparent viscosity over 0.85, HDT of 30℃ to 50℃ higher than that of poly (butylene-terephthalate) (PBT) for clay load from 1.0% to 10.0% (by mass), and higher capability to accommodate clay than other polymers. The nonisothermal crystallization experiments indicate that the better thermal degradation behavior and crystallization rate of NPBT are 50% higher than PBT, and its injection mould processing temperature is lowered from 110℃ to 55℃. NPBT samples are characterized by several techniques. X-ray shows an original clay interlayer distance enlarged from 1.0 nm to 2.5 nm, while both TBM and AFM indicate an average size from 30nm to lOOnm of exfoliated clay layers, and 3%(by mass) of particle agglomeration being phase separated from PBT matrix, which are factors on some mechanical properties decrease of NPBT. The disappearance of spherulitic morphology in NPBT resulted from layers nucleation is detected. Improving NPBT properties by treating clay with long chain organic reagent and controlling the way to load it is suggested.展开更多
Hybrid materials were prepared using a silane coupling agent, tetraethoxysilane ( TEOS ) as the precursor, dilute hydrochloric acid as the catalyst, and epoxy as the matrices. The films coated with hybrid materials ...Hybrid materials were prepared using a silane coupling agent, tetraethoxysilane ( TEOS ) as the precursor, dilute hydrochloric acid as the catalyst, and epoxy as the matrices. The films coated with hybrid materials were expected to improve abrasion resistance and mechanical properties. The morphology, mechanical properties, adhesion, and abrasion resistance of the polyethylene terephthalate (PET) films were characterized using an atomic force microscope, a tensile testing machine, a bagger knife, and a reciprocating fabric abrasion tester. The result of research indicated that the modification significantly affected the abrasion resistance and roughness. The-tensile strength and abrasion resistance of the modified PET films increased by 40% and 50% respectively at 3 % TEOS mass fraction.展开更多
The effects of different treatments, such as dry heat,wet heat, solvent vapor and ultrasonic, on propertiesof the cyclic oligomers on the surface of polyester fiberare studied. The components of surface oligomers area...The effects of different treatments, such as dry heat,wet heat, solvent vapor and ultrasonic, on propertiesof the cyclic oligomers on the surface of polyester fiberare studied. The components of surface oligomers areanalyzed through Thin-Layer Chromatograph. Theresult shows that: all of the treatment, especially solvent vapor treatment,call significantly increase the content of surface cyclic oligomers.The content of cyclic triIner is increased more considerably than other oligomers. Moreover,the morphology and thedistribution of surface cyclic oligomers are also different from different treatments:Dry heat and wet heat cause larger polygonal solids distributed evenly on the surface of fiber;solvent vapor nlakes fiber surface exhibit irregular rodlike crystal shapes randomly;ultrasonic treatment induces some obscureand smaller deposi^on the surface of fiber.展开更多
On the basis of melt-spinning, the dynamics model of polyethylene terephthalate (PET) hollow fiber is established. The effects of spinning conditions on hollow ratio are discussed and verified. Because of the differ...On the basis of melt-spinning, the dynamics model of polyethylene terephthalate (PET) hollow fiber is established. The effects of spinning conditions on hollow ratio are discussed and verified. Because of the different quenching conditions, there exist differences of the hollow ratio and the vitrification distances between different cycles. The important role of the quenching conditions on the meltspinning of PEr hollow fiber is also mentioned.展开更多
Poly(ethylene terephthalate)(PET)was synthesized by the in-situ polymerization method using layered double hydrotalcite(LDH)as the catalyst,and the thermal and flame retardation properties of PET were investigated as ...Poly(ethylene terephthalate)(PET)was synthesized by the in-situ polymerization method using layered double hydrotalcite(LDH)as the catalyst,and the thermal and flame retardation properties of PET were investigated as required.As identified by differential scanning calorimetry(DSC)and thermogravimetric(TGA)analysis,the crystallization rate and thermal degradation temperature of the as-prepared PET sample were enhanced compared with commercial PET sample.It was confirmed from the fire-resistant property study that the LDH can be used as an efficient flame-retardant besides functioning as a catalyst in the transesterification/polycondensation process for PET synthesis.展开更多
In reality, traditional process control system built upon centralized and hierarchical structures presents a weak response to change and is easy to shut down by single failure. Aiming at these problems, a new agent-ba...In reality, traditional process control system built upon centralized and hierarchical structures presents a weak response to change and is easy to shut down by single failure. Aiming at these problems, a new agent-based service-oriented integration architecture was proposed for chemical process automation system. Web services were dynamically orchestrated on the internet and agent behaviors were built in them. Data analysis, model, optimization, control, fault diagnosis and so on were capsuled into different web services. Agents were used for service compositions by negotiation. A prototype system of poly(ethylene terephthalate) process automation was used as the case study to demonstrate the validation of the integration.展开更多
In this study, Ultra High Performance Electrospray Ionization Ion Trap Time of Flight Mass Spectrometry (UHPLC-ESI-1T-TOF MS) method is used to screen the polymer additives in drinking water that is stored in Polyet...In this study, Ultra High Performance Electrospray Ionization Ion Trap Time of Flight Mass Spectrometry (UHPLC-ESI-1T-TOF MS) method is used to screen the polymer additives in drinking water that is stored in Polyethylene Terephthalate (PET) bottles. After directly analyzing the commercially available water samples, 3 polymer additives (chimassorb 81, irgafos 168 and oleamide) were detected. However, after exposure to sunshine for 8 days, two additional polymer additives (antioxidant 2246 and Butylated Hydroxytoluene (BHT)) were detected besides the former three additives.展开更多
A semicircular section tubular photoreactor has been constructed, characterized and applied to the treatment of groundwater contaminated with As(V) by means of the SORAS (solar oxidation and removal of arsenic) te...A semicircular section tubular photoreactor has been constructed, characterized and applied to the treatment of groundwater contaminated with As(V) by means of the SORAS (solar oxidation and removal of arsenic) technique, using ferrous and citrate salts. The solar concentrator was built with recyclable waste materials: glass tubes from fluorescent lamps and 6-inch diameter PVC pipes cut in half and covered by aluminum foil. The reactor concentrates solar radiation up to 2.8 times its natural intensity. Batch irradiation experiments followed by controlled agitation (shear rate = 30-33 s^-1; 20 min agitation period) showed that the photoreactor accelerates the formation of settleable floccules (Dp 〉 0.5mm), compared with a fluorescent lamp glass tube alone and a 2 L PET (polyethylene terephthalate) bottle. Irradiation times necessary for floccule formation in the photoreactor, the fluorescent lamp tube and the PET bottle were 15 min, 25 min and 60 min, respectively. Continuous flow experiments using a photoreactor with a photo-collection area of 0.9 m^2 and a hydraulic retention time (equal to the irradiation time) of 15 rain showed that immediate formation of floccules of good settleability occurs when the solution is subjected to moderate agitation (33 s^-1). An efficiency of 98.36% for As(V) removal was obtained with a final concentration of 16.5 ktg/L in decanted waters. In accordance to these results, the photoreactor is able to treat approximately 130 L/m^2 within a 5-h period with UVA irradiation intensities of 50-70 W/mE.展开更多
In this article, based on the analysis of the current environmental situation in Russia and other countries, as well as of the problem of recycling plastic waste in the Russian Federation (RF), the authors clearly s...In this article, based on the analysis of the current environmental situation in Russia and other countries, as well as of the problem of recycling plastic waste in the Russian Federation (RF), the authors clearly show the effectiveness of investments in the processing of polymer debris on the example of polyethylene terephthalate (PET) waste (granulates, flakes). In the frame of case study of social and environmental investment project on creating enterprise that will engage in collection, recycling, and sale of the consumer PET packaging in Russia, the authors demonstrate the economic feasibility of the creation of such kind of enterprises taking into account market conditions and the features of the existing system of taxation in Russia. The realization of the project will also help in solving environmental and social problems of large cities, in particular, will create more jobs (in terms of 6% of unemployment rate in the country). The study also identifies the main obstacles in the way of waste recycling in Russia, and the recommendations for improvement of normative base of the industry are given.展开更多
基金Supported by the Program of Jiangsu Development & Reform Commission(2005)the Industrial-ization Boosting Program of College Scientific Reserach Achievements of the Education Department of Jiangsu Province(JHB06-03)~~
文摘Nano-ZnO particle (nZnOp) reinforced polyethylene glycol (PEG)/polyethylene terephthalate (PET) (nZnOp/PEG/PET) copolymeric composites with different mass fractions and molecular weights of PEG are synthesized via in-situ polymerization. The dispersion of nZnOp in copolymer matrixes and the effects of PEG and nZnOp particles on the crystallization behavior of the composites are studied by TEM, differential scanning calorimetry(DSC), XRD and Fourier thansform infrared spectroscopy (FTIR ). The results reveal that nZnOp particles are dispersed in the matrixes with nano-scale, and the addition of PEG induces more homogeneous dispersion of nZnOp. Simultaneously, these nanoparticles become nucleating centers during the crystallization of the matrixes. PEG segments can improve the flexibility of the PET molecular chain, resulting in the drop of the cold crystallization temperature and the rise of the crystallization rate of the composites. Furthermore, PEG (4 000) with the mass fraction of 10% can promote the crystallization rate of the composites. The mechanical properties show that the nano-particles strengthen and toughen the PET matrix, whereas PEG weakens these improve- ments.
基金the National High Technology Research and Development Program of China(No.2003AA321010).
文摘Dimethyl carbonate (DMC) and poly(ethylene terephthalate) was simultaneously synthesized by the transesterification of ethylene carbonate (EC) with dimethyl terephthalate (DMT) in this paper. This reaction is an excellent green chemical process without poisonous substance. Various alkali metals were used as the catalysts. The results showed alkali metals had catalytic activity in a certain extent. The effect of reaction condition was also studied. When the reaction was carded out under the following conditions: the reaction temperature 250℃, molar ratio of EC to DMT 3 : 1, reaction time 3h, and catalyst amount 0.004 (molar ratio to DMT), the yield of DMC was 68.9%.
文摘In order to improve the wettability and biocompatibility of the poly (butylene terephthalate) non-woven (PBTNW), the method of surface modification is used to graft copolymerization of chitosan (CS) onto the PBTNW under alkylpolyglycoside (APG) inducing. The product is thoroughly characterized with the Fourier transform infrared spectroscopy (FrIR), the electron spectroscopy for chemical analysis (ESCA), the thermogravimetric (TG) and the scanning electron microscopy (SEM). It is found that chitosan is successfully grafted onto PBTNW. In addition, the water contact angles, hemolysis tests and cytotoxicity evaluation tests show an improvement in wettability and biocompatihility as a result of graft copolymerization of chitosan. So the CS-grafted PBTNW exhibits greater superiority than the original PBTNW. The CS-grafted PBTNW can be a candidate for blood filter materials and other medical applications.
文摘Nonisothermal crystallization behavior of poly(butylene adipate-co-terephthalate)(PBAT) synthesized via direct esterification and polycondensation reactions was investigated by the differential scanning calorimetry(DSC).The Avrami equation modified by Jeziorny and the Z.S.Mo equation were employed to describe the non-isothermal crystallization kinetics of copolyester samples.The test results showed that the Avrami equation was successful in describing nonisothermal crystallization process of PBAT copolyesters.PBAT copolyester could give birth to secondary crystallization.The crystallization parameter(Zc) increased with an increasing cooling rate and the Avrami exponent(n) was around 2.3.For a given cooling rate,the value of Zc demonstrated a sagging trend with an increase in adipic acid(AA) content.The equation proposed by Z.S.Mo was successful in describing the nonisothermal crystallization kinetics of PBAT copolyesters.
基金Supported by China National Petroleum Corporation Innovation Foundation(No.J02060)and Subsidized by Special Funds for Major State Basic Research Projects(No.G1999064800)
文摘In this paper, poly(butylene-terephthalate)-layered silicate of clay nanocomposites (NPBT) are reported. Their thermal properties, heat distortion temperature (HDT) and crystallization nucleation are investigated. NPBT samples have apparent viscosity over 0.85, HDT of 30℃ to 50℃ higher than that of poly (butylene-terephthalate) (PBT) for clay load from 1.0% to 10.0% (by mass), and higher capability to accommodate clay than other polymers. The nonisothermal crystallization experiments indicate that the better thermal degradation behavior and crystallization rate of NPBT are 50% higher than PBT, and its injection mould processing temperature is lowered from 110℃ to 55℃. NPBT samples are characterized by several techniques. X-ray shows an original clay interlayer distance enlarged from 1.0 nm to 2.5 nm, while both TBM and AFM indicate an average size from 30nm to lOOnm of exfoliated clay layers, and 3%(by mass) of particle agglomeration being phase separated from PBT matrix, which are factors on some mechanical properties decrease of NPBT. The disappearance of spherulitic morphology in NPBT resulted from layers nucleation is detected. Improving NPBT properties by treating clay with long chain organic reagent and controlling the way to load it is suggested.
基金Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education of China(No.2005-383)
文摘Hybrid materials were prepared using a silane coupling agent, tetraethoxysilane ( TEOS ) as the precursor, dilute hydrochloric acid as the catalyst, and epoxy as the matrices. The films coated with hybrid materials were expected to improve abrasion resistance and mechanical properties. The morphology, mechanical properties, adhesion, and abrasion resistance of the polyethylene terephthalate (PET) films were characterized using an atomic force microscope, a tensile testing machine, a bagger knife, and a reciprocating fabric abrasion tester. The result of research indicated that the modification significantly affected the abrasion resistance and roughness. The-tensile strength and abrasion resistance of the modified PET films increased by 40% and 50% respectively at 3 % TEOS mass fraction.
文摘The effects of different treatments, such as dry heat,wet heat, solvent vapor and ultrasonic, on propertiesof the cyclic oligomers on the surface of polyester fiberare studied. The components of surface oligomers areanalyzed through Thin-Layer Chromatograph. Theresult shows that: all of the treatment, especially solvent vapor treatment,call significantly increase the content of surface cyclic oligomers.The content of cyclic triIner is increased more considerably than other oligomers. Moreover,the morphology and thedistribution of surface cyclic oligomers are also different from different treatments:Dry heat and wet heat cause larger polygonal solids distributed evenly on the surface of fiber;solvent vapor nlakes fiber surface exhibit irregular rodlike crystal shapes randomly;ultrasonic treatment induces some obscureand smaller deposi^on the surface of fiber.
文摘On the basis of melt-spinning, the dynamics model of polyethylene terephthalate (PET) hollow fiber is established. The effects of spinning conditions on hollow ratio are discussed and verified. Because of the different quenching conditions, there exist differences of the hollow ratio and the vitrification distances between different cycles. The important role of the quenching conditions on the meltspinning of PEr hollow fiber is also mentioned.
文摘Poly(ethylene terephthalate)(PET)was synthesized by the in-situ polymerization method using layered double hydrotalcite(LDH)as the catalyst,and the thermal and flame retardation properties of PET were investigated as required.As identified by differential scanning calorimetry(DSC)and thermogravimetric(TGA)analysis,the crystallization rate and thermal degradation temperature of the as-prepared PET sample were enhanced compared with commercial PET sample.It was confirmed from the fire-resistant property study that the LDH can be used as an efficient flame-retardant besides functioning as a catalyst in the transesterification/polycondensation process for PET synthesis.
基金Supported by the Major State Basic Research Development Program of China(2012CB720500)the National Natural Science Foundation of China(U1162202,61222303)+2 种基金the Fundamental Research Funds for the Central Universities,Shanghai Municipal Natural Science Foundation(13ZR1411500)Shanghai R&D Platform Construction program(13DZ2295300)Shanghai Leading Academic Discipline Project(B504)
文摘In reality, traditional process control system built upon centralized and hierarchical structures presents a weak response to change and is easy to shut down by single failure. Aiming at these problems, a new agent-based service-oriented integration architecture was proposed for chemical process automation system. Web services were dynamically orchestrated on the internet and agent behaviors were built in them. Data analysis, model, optimization, control, fault diagnosis and so on were capsuled into different web services. Agents were used for service compositions by negotiation. A prototype system of poly(ethylene terephthalate) process automation was used as the case study to demonstrate the validation of the integration.
文摘In this study, Ultra High Performance Electrospray Ionization Ion Trap Time of Flight Mass Spectrometry (UHPLC-ESI-1T-TOF MS) method is used to screen the polymer additives in drinking water that is stored in Polyethylene Terephthalate (PET) bottles. After directly analyzing the commercially available water samples, 3 polymer additives (chimassorb 81, irgafos 168 and oleamide) were detected. However, after exposure to sunshine for 8 days, two additional polymer additives (antioxidant 2246 and Butylated Hydroxytoluene (BHT)) were detected besides the former three additives.
文摘A semicircular section tubular photoreactor has been constructed, characterized and applied to the treatment of groundwater contaminated with As(V) by means of the SORAS (solar oxidation and removal of arsenic) technique, using ferrous and citrate salts. The solar concentrator was built with recyclable waste materials: glass tubes from fluorescent lamps and 6-inch diameter PVC pipes cut in half and covered by aluminum foil. The reactor concentrates solar radiation up to 2.8 times its natural intensity. Batch irradiation experiments followed by controlled agitation (shear rate = 30-33 s^-1; 20 min agitation period) showed that the photoreactor accelerates the formation of settleable floccules (Dp 〉 0.5mm), compared with a fluorescent lamp glass tube alone and a 2 L PET (polyethylene terephthalate) bottle. Irradiation times necessary for floccule formation in the photoreactor, the fluorescent lamp tube and the PET bottle were 15 min, 25 min and 60 min, respectively. Continuous flow experiments using a photoreactor with a photo-collection area of 0.9 m^2 and a hydraulic retention time (equal to the irradiation time) of 15 rain showed that immediate formation of floccules of good settleability occurs when the solution is subjected to moderate agitation (33 s^-1). An efficiency of 98.36% for As(V) removal was obtained with a final concentration of 16.5 ktg/L in decanted waters. In accordance to these results, the photoreactor is able to treat approximately 130 L/m^2 within a 5-h period with UVA irradiation intensities of 50-70 W/mE.
文摘In this article, based on the analysis of the current environmental situation in Russia and other countries, as well as of the problem of recycling plastic waste in the Russian Federation (RF), the authors clearly show the effectiveness of investments in the processing of polymer debris on the example of polyethylene terephthalate (PET) waste (granulates, flakes). In the frame of case study of social and environmental investment project on creating enterprise that will engage in collection, recycling, and sale of the consumer PET packaging in Russia, the authors demonstrate the economic feasibility of the creation of such kind of enterprises taking into account market conditions and the features of the existing system of taxation in Russia. The realization of the project will also help in solving environmental and social problems of large cities, in particular, will create more jobs (in terms of 6% of unemployment rate in the country). The study also identifies the main obstacles in the way of waste recycling in Russia, and the recommendations for improvement of normative base of the industry are given.