The relation between structures and properties of polyurethane are investigated by modern physical and chemical methods.The results obtained are as follows:the effects of the content of self-crosslinking agent on the ...The relation between structures and properties of polyurethane are investigated by modern physical and chemical methods.The results obtained are as follows:the effects of the content of self-crosslinking agent on the properties of polyurethane,i.e.,dispersion stability,dynamical viscoelasticity and mechanical properties are discussed.It is found that the optimum molar ratio of epichlorohydrin and diethylenetriamine is 1:2.A mois-展开更多
Glycidyl acrylate was synthesized successfully utilizing phase - transfer catalyst and was applied to emulsion polymerization of acrylates as the crosslinking agent. Combined with other two kinds of crosslinking agent...Glycidyl acrylate was synthesized successfully utilizing phase - transfer catalyst and was applied to emulsion polymerization of acrylates as the crosslinking agent. Combined with other two kinds of crosslinking agents, a new type of ecofriendly self - crosslinking adhesive was prepared . Factors affecting the preparation such as reaction temperature, initiator, eniulsifiers, reaction time and so on were studied comprehensively. Properties in relation to pigment printing of the prepared adhesives were also tested and compared with two kinds of commercial adhesives that have been widely applied in printing industry.展开更多
The pyromellitic dianhydride（PMDA） crosslinked poly（vinyl alcohol）（PVA） was coated on top of the PAN ultrafiltration membrane to form a PVA/PAN composite PV membranes for wastewater desalination. The composite m...The pyromellitic dianhydride（PMDA） crosslinked poly（vinyl alcohol）（PVA） was coated on top of the PAN ultrafiltration membrane to form a PVA/PAN composite PV membranes for wastewater desalination. The composite membranes have high application value in industrial wastewater treatment. By varying the membrane fabrication parameters including the weight percent（wt%） of the PMDA, the crosslink temperature and duration, membrane with the best desalination performance was obtained. The composite membrane with a 2-lm-thick PVA selective layer containing 20 wt% of PMDA and being crosslinked at 100 °C for 2 h showed the highest Na Cl rejection of 99.98% with a water flux of 32.26 L/（m^2 h）at 70 °C using the 35,000 ppm Na Cl aqueous solution as feed. FTIR spectroscopy, wide-angle X-ray diffraction, thermogravimetric analysis and scanning electron microscope have been used to characterize the structures and properties of both the crosslinked PVA dense films and PVA/PAN composite membranes. The effects of the concentrations of PMDA,the crosslinking time and temperature to the membrane water contact angle, swelling degree, salt rejection and water flux were systematically studied.展开更多
This paper describes the self—adjustment of some tuning-knobs of the generalized predictive controller(GPC).A three feedforward neural network was utilized to on line learn two key tuning-knobs of GPC,and BP algorith...This paper describes the self—adjustment of some tuning-knobs of the generalized predictive controller(GPC).A three feedforward neural network was utilized to on line learn two key tuning-knobs of GPC,and BP algorithm was used for the training of the linking-weights of the neural network.Hence it gets rid of the difficulty of choosing these tuning-knobs manually and provides easier condition for the wide applications of GPC on industrial plants.Simulation results illustrated the effectiveness of the method.展开更多
The Belt and Road Initiative contains the aspiration of Chinese nation to pursue ideological freedom and desire of strengthening international exchanges and cooperation. This paper takes the Belt and Road Initiative f...The Belt and Road Initiative contains the aspiration of Chinese nation to pursue ideological freedom and desire of strengthening international exchanges and cooperation. This paper takes the Belt and Road Initiative for example,emphasizing the interpretation of the inheritance and development of Chinese culture so as to study the importance of Culture Self-Consciousness in Chinese Philosophy,in the context of English globalization. That is to say,this paper stresses the spirits and the stand of nation 's demonstration on pursuing peace,cooperation and sustainable development in the civilization continuity from traditional China to the contemporary China,with practical philosophic view.展开更多
Poly (β-carboxyethylmethylsiloxane)-LiClO_4 and poly (β-alkoxylethylmethylsiloxane)-LiClO_4 crosslinked fllms have been prepared. The ionic conductivity of the films depends on the polymer species, concentration of ...Poly (β-carboxyethylmethylsiloxane)-LiClO_4 and poly (β-alkoxylethylmethylsiloxane)-LiClO_4 crosslinked fllms have been prepared. The ionic conductivity of the films depends on the polymer species, concentration of lithium perchlorate, temperature and content of crosslinking agent. The effect of high polar organic solvent 1, 4-butyrolactone on the ionic conductivity and mechanical properties of poly (β-carhoxyethylmethylsiloxane )-LiClO_4 system was also investignied.展开更多
We have developed a hybrid hydrogel that is formed from a crosslinkable polymeric micelle and a polyamine. Under optimal conditions, the hydrogel rapidly formed in one second after a crosslinkable polymeric micelle so...We have developed a hybrid hydrogel that is formed from a crosslinkable polymeric micelle and a polyamine. Under optimal conditions, the hydrogel rapidly formed in one second after a crosslinkable polymeric micelle solution was mixed with a polyamine solution. We could change the hydrogel’s gelation properties, such as the storage modulus and gelation time by tuning the molecular weights of block copolymers and by tuning the pH of the dissolving-solvent of the hydrogel’s constituent components. Furthermore, we have clarified here that the structural difference among the micelles acting as crosslinkers can affect the gelation properties of the hydrogel. According to our findings, the hydrogel that was formed from the polymeric micelles possessing a highly packed (i.e., well-entangled or crosslinked) inner core exhibited a higher storage modulus than the hydrogel that was formed from the polymeric micelles possessing a lowly packed structure. Our results demonstrate that a microscopic structural difference among crosslinkers can induce a macroscopic change in the properties of the resulting hydrogels. For medical applications, the hydrogel proposed in the present paper can encapsulate the hydrophobic compounds in crosslinkers (polymeric micelles) so that the hydrogel can be available as the biomaterial for their sustained release.展开更多
文摘The relation between structures and properties of polyurethane are investigated by modern physical and chemical methods.The results obtained are as follows:the effects of the content of self-crosslinking agent on the properties of polyurethane,i.e.,dispersion stability,dynamical viscoelasticity and mechanical properties are discussed.It is found that the optimum molar ratio of epichlorohydrin and diethylenetriamine is 1:2.A mois-
文摘Glycidyl acrylate was synthesized successfully utilizing phase - transfer catalyst and was applied to emulsion polymerization of acrylates as the crosslinking agent. Combined with other two kinds of crosslinking agents, a new type of ecofriendly self - crosslinking adhesive was prepared . Factors affecting the preparation such as reaction temperature, initiator, eniulsifiers, reaction time and so on were studied comprehensively. Properties in relation to pigment printing of the prepared adhesives were also tested and compared with two kinds of commercial adhesives that have been widely applied in printing industry.
基金supported by the Higher Education and High-quality and World-class Universities (PY201618)the National Natural Science Foundation of China (Contract Grant Number 51373014)the National Natural Science Foundation of China (Contract Grant Number 51403012)
文摘The pyromellitic dianhydride（PMDA） crosslinked poly（vinyl alcohol）（PVA） was coated on top of the PAN ultrafiltration membrane to form a PVA/PAN composite PV membranes for wastewater desalination. The composite membranes have high application value in industrial wastewater treatment. By varying the membrane fabrication parameters including the weight percent（wt%） of the PMDA, the crosslink temperature and duration, membrane with the best desalination performance was obtained. The composite membrane with a 2-lm-thick PVA selective layer containing 20 wt% of PMDA and being crosslinked at 100 °C for 2 h showed the highest Na Cl rejection of 99.98% with a water flux of 32.26 L/（m^2 h）at 70 °C using the 35,000 ppm Na Cl aqueous solution as feed. FTIR spectroscopy, wide-angle X-ray diffraction, thermogravimetric analysis and scanning electron microscope have been used to characterize the structures and properties of both the crosslinked PVA dense films and PVA/PAN composite membranes. The effects of the concentrations of PMDA,the crosslinking time and temperature to the membrane water contact angle, swelling degree, salt rejection and water flux were systematically studied.
基金Supported by the National 863 CIMS Project Foundation(863-511-010)Tianjin Natural Science Foundation(983602011)Backbone Young Teacher Project Foundation of Ministry of Education
文摘This paper describes the self—adjustment of some tuning-knobs of the generalized predictive controller(GPC).A three feedforward neural network was utilized to on line learn two key tuning-knobs of GPC,and BP algorithm was used for the training of the linking-weights of the neural network.Hence it gets rid of the difficulty of choosing these tuning-knobs manually and provides easier condition for the wide applications of GPC on industrial plants.Simulation results illustrated the effectiveness of the method.
文摘The Belt and Road Initiative contains the aspiration of Chinese nation to pursue ideological freedom and desire of strengthening international exchanges and cooperation. This paper takes the Belt and Road Initiative for example,emphasizing the interpretation of the inheritance and development of Chinese culture so as to study the importance of Culture Self-Consciousness in Chinese Philosophy,in the context of English globalization. That is to say,this paper stresses the spirits and the stand of nation 's demonstration on pursuing peace,cooperation and sustainable development in the civilization continuity from traditional China to the contemporary China,with practical philosophic view.
文摘Poly (β-carboxyethylmethylsiloxane)-LiClO_4 and poly (β-alkoxylethylmethylsiloxane)-LiClO_4 crosslinked fllms have been prepared. The ionic conductivity of the films depends on the polymer species, concentration of lithium perchlorate, temperature and content of crosslinking agent. The effect of high polar organic solvent 1, 4-butyrolactone on the ionic conductivity and mechanical properties of poly (β-carhoxyethylmethylsiloxane )-LiClO_4 system was also investignied.
文摘We have developed a hybrid hydrogel that is formed from a crosslinkable polymeric micelle and a polyamine. Under optimal conditions, the hydrogel rapidly formed in one second after a crosslinkable polymeric micelle solution was mixed with a polyamine solution. We could change the hydrogel’s gelation properties, such as the storage modulus and gelation time by tuning the molecular weights of block copolymers and by tuning the pH of the dissolving-solvent of the hydrogel’s constituent components. Furthermore, we have clarified here that the structural difference among the micelles acting as crosslinkers can affect the gelation properties of the hydrogel. According to our findings, the hydrogel that was formed from the polymeric micelles possessing a highly packed (i.e., well-entangled or crosslinked) inner core exhibited a higher storage modulus than the hydrogel that was formed from the polymeric micelles possessing a lowly packed structure. Our results demonstrate that a microscopic structural difference among crosslinkers can induce a macroscopic change in the properties of the resulting hydrogels. For medical applications, the hydrogel proposed in the present paper can encapsulate the hydrophobic compounds in crosslinkers (polymeric micelles) so that the hydrogel can be available as the biomaterial for their sustained release.
