Thermoplastic starch is a kind of modified starch produced by mixing starch with additives and processing the mixture in an extruder. The mechanical properties, including tensile strength and elongation at break, biod...Thermoplastic starch is a kind of modified starch produced by mixing starch with additives and processing the mixture in an extruder. The mechanical properties, including tensile strength and elongation at break, biodegradability and rheological properties were studied. Glycerol and urea, to some extent, can both decrease the tensile strength and increase percentage elongation at break, because the former acts as a plasticizer and the latter can break down interactions among starch macromolecules. Thermoplastic starch shows thermoplasticity and its melt behaves as a pseudoplastic liquid at a low shear rate. Its biodegrading extent is slightly higher than that of native starch. The molecular weight of starch displays a decreasing tendency after thermoplastic modification.展开更多
In this paper,aliphatic amidediol was synthesized and mixed with glycerol used as a plasticizer for preparing thermoplastic starch（AGPTPS）.The yield of aliphatic amidediol was 91%.FF-IR expressed that the mixture of...In this paper,aliphatic amidediol was synthesized and mixed with glycerol used as a plasticizer for preparing thermoplastic starch（AGPTPS）.The yield of aliphatic amidediol was 91%.FF-IR expressed that the mixture of aliphatic amidediol and glycerol formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch.By scanning electron microscope（SEM）native cornstarch granules were proved to transfer to a homogeneous continuous system.After being stored for a period time at room temperature,the mechanical properties of AGPTPS were also studied.As a mixed plasticizer,aliphatic amidediol and glycerol would be practical to extend TPS application scopes.展开更多
in this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch （TPS）. FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen...in this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch （TPS）. FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch. X-ray diffraction （XRD） showed that the typical A-style crystallinity in the native starch has been destructed. By scanning electron microscope （SEM） native cornstarch granules were proved to transfer to a homogeneous system. After being stored for one week at RH=33%, the mechanical properties of EPTPS was also studied. The elongation reached to 264% utmost. As a novel plasticizer, ethylenebisformamide would be practical to extend TPS application scopes.展开更多
Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermo...Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermoplastic starch (TPS) is produced from starch processed at high temperatures in the presence of plasticizers, such as water and glycerol. However, because of its hydrophilic nature, TPS exhibits poor mechanical properties when exposed to environmental conditions, such as rain or humidity. The overall objective of this research work was to produce a thermoplastic starch based material with low water absorption that may be used to replace petroleum-based plastics. With a recent emergence of “green” polyethylene (GPE), sourced from renewable feedstock, it has become possible to develop novel biodegradable polymers for various applications. In this work, GPE was melt blended with starch in three different ways;reactive extrusion of GPE and starch facilitated by maleic anhydride (MAH) and dicumyl peroxide (DCP), melt blending of GPE and starch by extrusion, and melt blending of maleated polyethylene and starch by extrusion. Comprehensive testing and analysis has shown that all methods reduced water absorption significantly with some variations across the board.展开更多
Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results...Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.展开更多
As one type of environment-friendly polymer, biodegradable starch-based materials have been widely explored in recent years and considered one of the most promising plastics in the future. Currently, either synthetic ...As one type of environment-friendly polymer, biodegradable starch-based materials have been widely explored in recent years and considered one of the most promising plastics in the future. Currently, either synthetic biodegradable aliphatic polyesters or certain natural polymers are usually blended with thermoplastic starch to enhance hydrophobicity and service performance of starch-based materials. The main deficiency lies in the low compatibility between starch and polyester phases. Therefore amphiphilic compatibilizers, such as hydroxyl functioned polyesters, need to be developed in the future. Moreover, multi-phase blending systems including two or more polyester phases are also supposed to be designed.展开更多
The use of plastics from petrochemical resources poses environmental impacts, and one of the alternative solutions is the use of starch. The objective of this present work has been to present the literature on starch,...The use of plastics from petrochemical resources poses environmental impacts, and one of the alternative solutions is the use of starch. The objective of this present work has been to present the literature on starch, and to highlight the debate in the development of composite films. The approach adopted was to present the state of the art on starch and thermoplastic starch matrix composites. The work shows that starch is available worldwide and can be used in the manufacture of biodegradable plastics;the debate remains on the reinforcement of thermoplastic starch to improve its physical and mechanical properties poor;then researchers must diversify the reinforcements to see the impact on the properties of thermoplastic starch.展开更多
Bio plastics products have a rapid growing demand and market across the globe. Polymers synthesized from renewable resources have gained immense popularity, in numerous applications ranging from films, bottles, food p...Bio plastics products have a rapid growing demand and market across the globe. Polymers synthesized from renewable resources have gained immense popularity, in numerous applications ranging from films, bottles, food packaging, drug delivery, bags to agriculture mulch films. Various naturally occurring resources available for starch and PLA extraction and the associated polymer processing techniques are discussed. Alongside some basic concepts on blown film extrusion, the modifications needed for such specialized polymer processing techniques are also explored, giving a comprehensive outlook on bioplastics. Special process analysis, for its application as films are discussed. In the current scenario, as the world aspires for environmental and polymer sustainability, Bioplastic products are of high value. The review article would be beneficial to those embarked on designing bio-plastics products from renewable resources.展开更多
文摘Thermoplastic starch is a kind of modified starch produced by mixing starch with additives and processing the mixture in an extruder. The mechanical properties, including tensile strength and elongation at break, biodegradability and rheological properties were studied. Glycerol and urea, to some extent, can both decrease the tensile strength and increase percentage elongation at break, because the former acts as a plasticizer and the latter can break down interactions among starch macromolecules. Thermoplastic starch shows thermoplasticity and its melt behaves as a pseudoplastic liquid at a low shear rate. Its biodegrading extent is slightly higher than that of native starch. The molecular weight of starch displays a decreasing tendency after thermoplastic modification.
文摘In this paper,aliphatic amidediol was synthesized and mixed with glycerol used as a plasticizer for preparing thermoplastic starch（AGPTPS）.The yield of aliphatic amidediol was 91%.FF-IR expressed that the mixture of aliphatic amidediol and glycerol formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch.By scanning electron microscope（SEM）native cornstarch granules were proved to transfer to a homogeneous continuous system.After being stored for a period time at room temperature,the mechanical properties of AGPTPS were also studied.As a mixed plasticizer,aliphatic amidediol and glycerol would be practical to extend TPS application scopes.
文摘in this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch （TPS）. FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch. X-ray diffraction （XRD） showed that the typical A-style crystallinity in the native starch has been destructed. By scanning electron microscope （SEM） native cornstarch granules were proved to transfer to a homogeneous system. After being stored for one week at RH=33%, the mechanical properties of EPTPS was also studied. The elongation reached to 264% utmost. As a novel plasticizer, ethylenebisformamide would be practical to extend TPS application scopes.
文摘Novel plastics that are biodegradable, environmentally benign, and made from renewable natural resources are currently being researched as alternatives to traditional petroleum-based plastics. One such plastic, thermoplastic starch (TPS) is produced from starch processed at high temperatures in the presence of plasticizers, such as water and glycerol. However, because of its hydrophilic nature, TPS exhibits poor mechanical properties when exposed to environmental conditions, such as rain or humidity. The overall objective of this research work was to produce a thermoplastic starch based material with low water absorption that may be used to replace petroleum-based plastics. With a recent emergence of “green” polyethylene (GPE), sourced from renewable feedstock, it has become possible to develop novel biodegradable polymers for various applications. In this work, GPE was melt blended with starch in three different ways;reactive extrusion of GPE and starch facilitated by maleic anhydride (MAH) and dicumyl peroxide (DCP), melt blending of GPE and starch by extrusion, and melt blending of maleated polyethylene and starch by extrusion. Comprehensive testing and analysis has shown that all methods reduced water absorption significantly with some variations across the board.
基金Funded by the Fundamental Research Funds for the Central Universities(DL13CB13)the China Postdoctoral Science Foundation Funded Project(No.2014M550178)the National Natural Science Foundation of China(No.31200442)
文摘Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch（TPS） from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.
文摘As one type of environment-friendly polymer, biodegradable starch-based materials have been widely explored in recent years and considered one of the most promising plastics in the future. Currently, either synthetic biodegradable aliphatic polyesters or certain natural polymers are usually blended with thermoplastic starch to enhance hydrophobicity and service performance of starch-based materials. The main deficiency lies in the low compatibility between starch and polyester phases. Therefore amphiphilic compatibilizers, such as hydroxyl functioned polyesters, need to be developed in the future. Moreover, multi-phase blending systems including two or more polyester phases are also supposed to be designed.
文摘The use of plastics from petrochemical resources poses environmental impacts, and one of the alternative solutions is the use of starch. The objective of this present work has been to present the literature on starch, and to highlight the debate in the development of composite films. The approach adopted was to present the state of the art on starch and thermoplastic starch matrix composites. The work shows that starch is available worldwide and can be used in the manufacture of biodegradable plastics;the debate remains on the reinforcement of thermoplastic starch to improve its physical and mechanical properties poor;then researchers must diversify the reinforcements to see the impact on the properties of thermoplastic starch.
文摘Bio plastics products have a rapid growing demand and market across the globe. Polymers synthesized from renewable resources have gained immense popularity, in numerous applications ranging from films, bottles, food packaging, drug delivery, bags to agriculture mulch films. Various naturally occurring resources available for starch and PLA extraction and the associated polymer processing techniques are discussed. Alongside some basic concepts on blown film extrusion, the modifications needed for such specialized polymer processing techniques are also explored, giving a comprehensive outlook on bioplastics. Special process analysis, for its application as films are discussed. In the current scenario, as the world aspires for environmental and polymer sustainability, Bioplastic products are of high value. The review article would be beneficial to those embarked on designing bio-plastics products from renewable resources.
