In this study,the effect of hot calendering process on the microstructure and properties of poly(p-phenylene terephthalamide)(PPTA) paper-based materials was investigated.The microstructures of the fracture surface,cr...In this study,the effect of hot calendering process on the microstructure and properties of poly(p-phenylene terephthalamide)(PPTA) paper-based materials was investigated.The microstructures of the fracture surface,crystalline structure,and single fiber strength of the PPTA paperbased materials as well as the different bonding behaviors between the PPTA fibers and PPTA fibrids obtained before and after the hot calendering process were examined.The results indicated that a high linear pressure would result in a limited improvement of the strength owing to the unimproved paper structure.The optimal values of tensile index and dielectric strength of 56.6 N·m/g and 27.6 kV/mm,respectively,could only be achieved with a synergistic effects of hot calendering temperature and linear pressure(240℃ and 110 k N/m,respectively).This result suggested it was possible to achieve a significant reinforcement and improvement in the interfacial bonding of functional PPTA paper-based materials,and avoid the formation of unexpected pleats and cracks in PPTA paper-based materials during the hot calendering process.展开更多
A method for making a automobile filter which includes impregnating a filter paper with a cross-linkable binder composition is discussed in the article. The water-based binder comprises a latex containing 80 wt% acryl...A method for making a automobile filter which includes impregnating a filter paper with a cross-linkable binder composition is discussed in the article. The water-based binder comprises a latex containing 80 wt% acrylic acid in the latex solids, and 20 wt% melthyl methacrylate, the binder also contains 5 parts of a cross-linking resin per 100 weight parts of latex solids and 5% parts of catalyst for the cross-linking resin based on the weight of the cross-linking resin. 4 wt% water-based polymer emulsion, on a solids basis, which is used to impregnate filter paper and rigidify it. Such impregnated filter paper has good dry and wet tensile strength and stiffness. The method has no impairing to the environment.展开更多
Zinc and its compounds, alloys and composites play an important role in the modern day world and find application in almost every aspect that can improve the quality of our lives. This ranges from supplements and phar...Zinc and its compounds, alloys and composites play an important role in the modern day world and find application in almost every aspect that can improve the quality of our lives. This ranges from supplements and pharmaceuticals that are meant to improve our health and wellbeing to additives meant to guard or reduce corrosion in metals. However, over the past several years, a new area of technology has been garnering a great deal of attention and has made use of zinc and its compounds. This is with reference to paper-based microfluidic technology that offers several advantages and that keeps expanding in the amount of applications it covers. In this paper, a review is offered for the applications that have used zinc or zinc compounds in paper-based microfluidic devices.展开更多
Lithium-ion (Li-ion) batteries have been fabricated in various ways to improve flexibility. Flexibility could be enhanced via active materials, separators, electrodes, and electrolytes, which could then be integrated ...Lithium-ion (Li-ion) batteries have been fabricated in various ways to improve flexibility. Flexibility could be enhanced via active materials, separators, electrodes, and electrolytes, which could then be integrated to form flexible electronic devices with promising electrochemical properties compared to traditional non-flexible Li-ion batteries. Recent progress towards flexible Li-</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">ion batteries fabrication, materials, and their electrochemical properties are investigated in this review. Additionally, recent developments in electronic devices utilizing flexible batteries and their future applications are explored. Portable and wearable electronics, as the primary beneficiaries of the flexible, rechargeable, and high-performance Li-ion batteries, are examined. In the end, various applications and challenges of flexible batteries in healthcare and various energy storage systems, considering practical implementation, are argued.展开更多
TOEFL, which aims to measure the English proficiency of test-takers whose first language is not English, is a familiar test to students around the world. The number of people who take the TEOFL is growing rapidly as t...TOEFL, which aims to measure the English proficiency of test-takers whose first language is not English, is a familiar test to students around the world. The number of people who take the TEOFL is growing rapidly as the influence of the TOEFL is expanding. In 2002-2003, the computer-based TOEFL test will be introduced into China to replace the old paper-based test. So it is quite necessary for people who are preparing to take the computer-based TOEFL test to learn something about it.展开更多
Today, packaging plays a crucial role in maintaining the quality of products during uses by providing safeguarding against physical, chemical and environmental challenges. While polymer-based packaging material has be...Today, packaging plays a crucial role in maintaining the quality of products during uses by providing safeguarding against physical, chemical and environmental challenges. While polymer-based packaging material has been very extensively used, there has been a recent move to paper-based packaging products because of their economic and environmentally-friendly nature. Currently, Paper and paper-based board materials have been used as packaging material for food products, and e-commerce business. Adhesives in packaging industries are critical to the structure of most paper and paper board packaging, whether applied during the process of conversion and on the packaging line. From a production point of view, adhesive choice can significantly affect process line efficiency and production performance. Adhesive types used in paper industries are water-based adhesives both synthetic and bio-polymer based (starch, cellulose, protein and itaconic acid), Solvent-based adhesives (polyurethane and acrylic-based) and 100% solids adhesives like heat sealing adhesive and hot melts. More recently, water-based heat-expandable adhesive having thermally insulative and cushion-like properties has been provided for use in protective packages and wrap. Here, we aim to present an overview of the research trend of adhesives in the paper packaging industry. The overview summarizes the different adhesives for paper packaging industries.展开更多
基金the financial support to this research from the open fund of state key laboratory for modification of chemical fibers and polymer materials (LK1601)projects of education department of Shaanxi provincial government (15JF012)National Natural Science Foundation of China (51402180)
文摘In this study,the effect of hot calendering process on the microstructure and properties of poly(p-phenylene terephthalamide)(PPTA) paper-based materials was investigated.The microstructures of the fracture surface,crystalline structure,and single fiber strength of the PPTA paperbased materials as well as the different bonding behaviors between the PPTA fibers and PPTA fibrids obtained before and after the hot calendering process were examined.The results indicated that a high linear pressure would result in a limited improvement of the strength owing to the unimproved paper structure.The optimal values of tensile index and dielectric strength of 56.6 N·m/g and 27.6 kV/mm,respectively,could only be achieved with a synergistic effects of hot calendering temperature and linear pressure(240℃ and 110 k N/m,respectively).This result suggested it was possible to achieve a significant reinforcement and improvement in the interfacial bonding of functional PPTA paper-based materials,and avoid the formation of unexpected pleats and cracks in PPTA paper-based materials during the hot calendering process.
文摘A method for making a automobile filter which includes impregnating a filter paper with a cross-linkable binder composition is discussed in the article. The water-based binder comprises a latex containing 80 wt% acrylic acid in the latex solids, and 20 wt% melthyl methacrylate, the binder also contains 5 parts of a cross-linking resin per 100 weight parts of latex solids and 5% parts of catalyst for the cross-linking resin based on the weight of the cross-linking resin. 4 wt% water-based polymer emulsion, on a solids basis, which is used to impregnate filter paper and rigidify it. Such impregnated filter paper has good dry and wet tensile strength and stiffness. The method has no impairing to the environment.
文摘Zinc and its compounds, alloys and composites play an important role in the modern day world and find application in almost every aspect that can improve the quality of our lives. This ranges from supplements and pharmaceuticals that are meant to improve our health and wellbeing to additives meant to guard or reduce corrosion in metals. However, over the past several years, a new area of technology has been garnering a great deal of attention and has made use of zinc and its compounds. This is with reference to paper-based microfluidic technology that offers several advantages and that keeps expanding in the amount of applications it covers. In this paper, a review is offered for the applications that have used zinc or zinc compounds in paper-based microfluidic devices.
文摘Lithium-ion (Li-ion) batteries have been fabricated in various ways to improve flexibility. Flexibility could be enhanced via active materials, separators, electrodes, and electrolytes, which could then be integrated to form flexible electronic devices with promising electrochemical properties compared to traditional non-flexible Li-ion batteries. Recent progress towards flexible Li-</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">ion batteries fabrication, materials, and their electrochemical properties are investigated in this review. Additionally, recent developments in electronic devices utilizing flexible batteries and their future applications are explored. Portable and wearable electronics, as the primary beneficiaries of the flexible, rechargeable, and high-performance Li-ion batteries, are examined. In the end, various applications and challenges of flexible batteries in healthcare and various energy storage systems, considering practical implementation, are argued.
文摘TOEFL, which aims to measure the English proficiency of test-takers whose first language is not English, is a familiar test to students around the world. The number of people who take the TEOFL is growing rapidly as the influence of the TOEFL is expanding. In 2002-2003, the computer-based TOEFL test will be introduced into China to replace the old paper-based test. So it is quite necessary for people who are preparing to take the computer-based TOEFL test to learn something about it.
文摘Today, packaging plays a crucial role in maintaining the quality of products during uses by providing safeguarding against physical, chemical and environmental challenges. While polymer-based packaging material has been very extensively used, there has been a recent move to paper-based packaging products because of their economic and environmentally-friendly nature. Currently, Paper and paper-based board materials have been used as packaging material for food products, and e-commerce business. Adhesives in packaging industries are critical to the structure of most paper and paper board packaging, whether applied during the process of conversion and on the packaging line. From a production point of view, adhesive choice can significantly affect process line efficiency and production performance. Adhesive types used in paper industries are water-based adhesives both synthetic and bio-polymer based (starch, cellulose, protein and itaconic acid), Solvent-based adhesives (polyurethane and acrylic-based) and 100% solids adhesives like heat sealing adhesive and hot melts. More recently, water-based heat-expandable adhesive having thermally insulative and cushion-like properties has been provided for use in protective packages and wrap. Here, we aim to present an overview of the research trend of adhesives in the paper packaging industry. The overview summarizes the different adhesives for paper packaging industries.
