Adhesive capacity of quaternary ammonium starch and starch phosphate to the polyester / cotton fibers was studied by means roving method for the purpose of improving the sizing performance and decreasing the cost. By ...Adhesive capacity of quaternary ammonium starch and starch phosphate to the polyester / cotton fibers was studied by means roving method for the purpose of improving the sizing performance and decreasing the cost. By introducing different amount of quaternary ammonium or phosphate groups onto starch molecules, the modified starch with a series of defferent degree of substitution was prepared. Therefore the regularity of adhesive capacity, extended property and size-absorbing ability with the change in degree of substitution (DS) was obtained through the researches. The experiments demonstrate that the DS of the two modified starches show a marked influence upon the properties mentioned above. The starch phosphate is superior to quaternary ammonium starch as warp size for polyester / cotton yarns from the viewpoint of adhesive capacity and cost, although both of them are better than natural one. To improve the adhesive capacity to polyester / cotton fibers, DS≥0.027 is necessary for quaternary ammonium展开更多
The advantages of using starch graft copolymers as warp sizes in textile were briefly discussed, and the factors of affecting adhesive capacity to the fiber were analysed. By using eerie ammonium nitrate as an initiat...The advantages of using starch graft copolymers as warp sizes in textile were briefly discussed, and the factors of affecting adhesive capacity to the fiber were analysed. By using eerie ammonium nitrate as an initiator under nitrogen atomosphere, a number of vinyl and/or acrylic monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, butyl methacrylate, vinyl acetate and the combinations among them were graft copolymerized respectively onto granular corn starch in aqueous dispersion. The adhesive capacity of these starch graft copolymers to polyester/cotton fibers was evaluated by a slightly sized rovings according to V. K. Aggarwal’s method which measures the breaking strength and elongation of the rovings impregnated with the size paste. The influences of the monomers and their combinations, the grafting technological processes and the pretreatment methods before graft copolymerization upon adhesive capacity have been展开更多
Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as p...Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as petroleum and natural gas [1] [2], would be gradually replaced by renewable biopolymers. Starch is a relatively inexpensive and renewable product from abundant plants, easy processing and it has been extensively used as binders, sizing materials, glues and pastes [3], but its bonding capacity is not strong enough to glue wood [4]. Extensive research has been carried out on improving the cohesive properties, especially water resistance, of starch-based adhesives. In starch-based wood adhesive many new approaches have come forward for effective use it in wood/wood composite adhesive giving comparable performance as synthetic adhesives. This review of starch-based adhesives is made with the focus on starch modification methods for improving properties of starch-based adhesives.展开更多
The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood wa...The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood was pressed with the prepared adhesive and the bonding strength of the plywood was tested to analyze thedifference among the adhesives from different plant sources and the difference after blending PAPI prepolymer.FT-IR results showed that the hydroxyl peak of cassava starch was stronger and wider. TGA showed that the residue of cassava starch was lower, but the thermal stability of cassava starch was almost the same. XPS data showedthat the oxygen content of cassava starch was slightly higher, but the carbon content was slightly lower. SEM analysis showed that corn starch granules were more irregular and sharper than cassava starch, and cassava starchgranules were more uniform, regular and round.展开更多
Currently there has been a growing interest in substituting traditional synthetic polymers with biobased renewable polymers for adhesive applications. However, biobased renewable polymers such as starch suffer from fe...Currently there has been a growing interest in substituting traditional synthetic polymers with biobased renewable polymers for adhesive applications. However, biobased renewable polymers such as starch suffer from few draw-backs like poor water resistance and mechanical strength. To become important potential alternatives of synthetic polymers, starch must have comparable physical, chemical, thermal and mechanical properties to that of synthetic polymers. To achieve this, starch has been modified by a series of crosslinkers like boric acid, citric acid, glyoxal, gluteraldehyde, etc. and silane modification. Silane modification by chloropropyl trimethoxysilane, γ-Methacryloxypropyl trimethoxy silane and vinyl trimethoxy silane is a suitable method to improve the performance in terms of mechanical and thermally. Silane forms covalent bonds with starch during starch modification resulted in enhanced shear strength and storage stability. A new research on biodegradable, renewable, environmentally friendly silane modification of starch-based wood adhesive that was prepared by reacting with various silanes. This paper, we reviewed silane as a modifying agent for starch-based wood adhesive.展开更多
Interactions between different components in α-starch based composite binder for green sand mould/core were investigated by using XRD, IR spectra, 1H NMR spectra and SEM. Several adhesive hardening structures and the...Interactions between different components in α-starch based composite binder for green sand mould/core were investigated by using XRD, IR spectra, 1H NMR spectra and SEM. Several adhesive hardening structures and theories of the binder at room temperature were proposed according to the interactions between various compositions. Thus, the reasons for the binder to have excellent combination properties and unique adhesive bonding and self-curing characteristics were explained by these theories successfully. And the theories are of great directive importance to design and development of composite binder for green sand mould/core.展开更多
With the exponential growth of the computing power,machine learning techniques have been successully used in various applications.This paper intended to predict and optimize the shear strength of single lap cassava st...With the exponential growth of the computing power,machine learning techniques have been successully used in various applications.This paper intended to predict and optimize the shear strength of single lap cassava starch-based adhesive joints for comparison with the application of artificial intelligence(AI)methods.The shear strength was firstly determined by the experiment with three independent experimental variables(starch content,NaOH concentration and reaction temperature).The analysis of range(ANORA)and analysis of variance(ANOVA)were applied to investigate the optimal combination and the significance of each factor for the shear strength based on the orthogonal experiment.The performance of all AI models was char acterized by mean absolute error(MAE),root mean square error(RMSE)and regression coefficient(R^(2))compared with the experi-mental ones.The GA optimized ANN model was combined with the genetic algorithm(GA)to find the optimal combination of factors for the finalized optimized cassava starch adhesives(CSA-OP).The physicochemical prop-erties of the cassava starch and CSA-OP were determined by the FTIR,TGA and SEM EDS,respectively.The results showed that the numerical optimized condition of the GA optimized ANN model was superior to the orthogonal experimental optimized condition.The sensitivity analysis revealed that the relative importance of variables was consistent with the results from ANOVA.FTIR results showed that there were high hydroxyl groups in cassava starch.TGA results showed that the residue of CSA OP was higher than the assava starch.SEM EDS results showed that both the cassava starch and CSA OP had abundant carbon and oxygen functional groups.Consequently,the obtained results revealed that the use of AI methods was an adequate approach to model and optimize the experimental variables of the shear strength of single lap cassava starch-based adhesive joints.展开更多
Bio-degradable cassava starch-based adhesives were produced from chemically gelatinized starch formulations. The varying combinations of process parameters applied include: concentration of gelatinization modifier, ma...Bio-degradable cassava starch-based adhesives were produced from chemically gelatinized starch formulations. The varying combinations of process parameters applied include: concentration of gelatinization modifier, mass % borax/starch, and temperature of reaction mixture. The physico-chemical parameters for characterizing the adhesive samples were viscosity, density, pH and bonding strength. The effects of the variation of process parameters on the quality of the adhesives were assessed using response surface (central composite) designs with 2 factors, to relate the highest adhesive quality with the optimal combination of process factors. The adhesives produced using HCl as the gelatinization modifier were of a higher quality than those produced using NaOH with one of the most important quality assessment parameters which is the bond strength being 22.31 kPa at 0.01 M and 20% mass borax/starch and 11.60 kPa at 0.01 M and 8% mass borax/starch for HCl and NaOH respectively. The experimental results demonstrated that the optimal temperature for the production of the adhesive was 85˚C.展开更多
A series of dodecenylsuccinylated starches( DSSs) with different degree of substitution( DS) were prepared via the esterification of dodencenylsuccinic anhydride with hydrolyzed cornstarch in aqueous dispersion for in...A series of dodecenylsuccinylated starches( DSSs) with different degree of substitution( DS) were prepared via the esterification of dodencenylsuccinic anhydride with hydrolyzed cornstarch in aqueous dispersion for investigating the influences of starch dodecenylsuccinylation upon the performances such as apparent viscosity and surface tension of starch paste, film behaviors,and adhesion to fibers for warp sizing. It was found that the dodecenylsuccinylation was able to reduce the surface tension of cooked starch paste and enhance the adhesion of starch to polyester fibers. It was also capable of depressing the brittleness of native starch and improving the mechanical behaviours such as breaking elongation and work-to-break of starch film. Initial increase in DS level of dodecenylsuccinylation enhanced these positive effects,while excessively increasing the level resulted in marked reduction in tensile strength of starch film and significant decrement in reaction efficiency. X-ray diffraction patterns of starch films showed the dodecenylsuccinates derivatized onto the backbones of starch depressed the degree of crystallinity of starch film. Based on the paste behaviors, adhesion, and film properties, the dodecenylsuccinylation level is recommended in a range of 0. 015-0. 025 for sizing polyester warps.展开更多
Influences of some electrolyte impurities within starch and starch cationization on the adhesion of quaternary ammonium cornstarch to cotton and polyester fibers were investigated. The electrolytes considered incl...Influences of some electrolyte impurities within starch and starch cationization on the adhesion of quaternary ammonium cornstarch to cotton and polyester fibers were investigated. The electrolytes considered included NaCI, Na2SO4, NaH2PO4 and Na2HPO4. The adhesion to fibers was evaluated in terms of maximum strength and work-to-break of the roving sized with the starch pastes containing electrolytes. It was found that the cationization showed a positive effect on the adhesion to both fibers whereas the electrolytes gave an adverse effect and reduced the adhesion. The adverse effect depends on the type and amount of electrolytes. The influence of electrolytes on the adhesion can be ranked in a series of NaH2PO4〉 Na2 HPO4〉 Na2SO4 〉 NaCl. The adhesion enhances as the modification extent increases and the electrolyte content decreases. Furthermore, the adverse effect can be compensated by the positive effect of the starch modification even at a low modification extent. If the electrolytes are fully eliminated, the cationic starch can increase the adhesion strength by more than 10% for both fibers.展开更多
Hot-melt (HM) adhesives offer advantages over their contemporary water-based and solvent-based adhesives like low volatile organic compounds (VOCs), 100% solid, fast drying, setting etc. In recent years, to reduce the...Hot-melt (HM) adhesives offer advantages over their contemporary water-based and solvent-based adhesives like low volatile organic compounds (VOCs), 100% solid, fast drying, setting etc. In recent years, to reduce their dependence on dwindling petroleum resources and due to the enormous use of HM adhesives in packaging areas that demand 100% recyclability, efforts have been devoted to making these formulations completely bio-based, sustainable and biodegradable. In this attempt, research and developments have been focused on using starch, modified starch, soy protein, polylactides, polyamides, lignin and vegetable oils as a partial/fully replacement to the petrochemical</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">based polymers. The huge amount of research going on in the field of bio-based polymers has still not reached its complete potential in the field of HM adhesives. In this review paper</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> HM adhesives based on sustainable raw materials namely starch, modified starch, polyamides, poly (lactic acid), soy protein and lignin are discussed.展开更多
文摘Adhesive capacity of quaternary ammonium starch and starch phosphate to the polyester / cotton fibers was studied by means roving method for the purpose of improving the sizing performance and decreasing the cost. By introducing different amount of quaternary ammonium or phosphate groups onto starch molecules, the modified starch with a series of defferent degree of substitution was prepared. Therefore the regularity of adhesive capacity, extended property and size-absorbing ability with the change in degree of substitution (DS) was obtained through the researches. The experiments demonstrate that the DS of the two modified starches show a marked influence upon the properties mentioned above. The starch phosphate is superior to quaternary ammonium starch as warp size for polyester / cotton yarns from the viewpoint of adhesive capacity and cost, although both of them are better than natural one. To improve the adhesive capacity to polyester / cotton fibers, DS≥0.027 is necessary for quaternary ammonium
文摘The advantages of using starch graft copolymers as warp sizes in textile were briefly discussed, and the factors of affecting adhesive capacity to the fiber were analysed. By using eerie ammonium nitrate as an initiator under nitrogen atomosphere, a number of vinyl and/or acrylic monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, butyl methacrylate, vinyl acetate and the combinations among them were graft copolymerized respectively onto granular corn starch in aqueous dispersion. The adhesive capacity of these starch graft copolymers to polyester/cotton fibers was evaluated by a slightly sized rovings according to V. K. Aggarwal’s method which measures the breaking strength and elongation of the rovings impregnated with the size paste. The influences of the monomers and their combinations, the grafting technological processes and the pretreatment methods before graft copolymerization upon adhesive capacity have been
文摘Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as petroleum and natural gas [1] [2], would be gradually replaced by renewable biopolymers. Starch is a relatively inexpensive and renewable product from abundant plants, easy processing and it has been extensively used as binders, sizing materials, glues and pastes [3], but its bonding capacity is not strong enough to glue wood [4]. Extensive research has been carried out on improving the cohesive properties, especially water resistance, of starch-based adhesives. In starch-based wood adhesive many new approaches have come forward for effective use it in wood/wood composite adhesive giving comparable performance as synthetic adhesives. This review of starch-based adhesives is made with the focus on starch modification methods for improving properties of starch-based adhesives.
基金This work was supported by the National Natural Science Foundation of China(No.31670569)the Fundamental Research Funds for the Central Universities(No.2572019CG05)Special thanks to the support of the Chinese University Students,Innovation and Entrepreneurship Project(202010225071).
文摘The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood was pressed with the prepared adhesive and the bonding strength of the plywood was tested to analyze thedifference among the adhesives from different plant sources and the difference after blending PAPI prepolymer.FT-IR results showed that the hydroxyl peak of cassava starch was stronger and wider. TGA showed that the residue of cassava starch was lower, but the thermal stability of cassava starch was almost the same. XPS data showedthat the oxygen content of cassava starch was slightly higher, but the carbon content was slightly lower. SEM analysis showed that corn starch granules were more irregular and sharper than cassava starch, and cassava starchgranules were more uniform, regular and round.
文摘Currently there has been a growing interest in substituting traditional synthetic polymers with biobased renewable polymers for adhesive applications. However, biobased renewable polymers such as starch suffer from few draw-backs like poor water resistance and mechanical strength. To become important potential alternatives of synthetic polymers, starch must have comparable physical, chemical, thermal and mechanical properties to that of synthetic polymers. To achieve this, starch has been modified by a series of crosslinkers like boric acid, citric acid, glyoxal, gluteraldehyde, etc. and silane modification. Silane modification by chloropropyl trimethoxysilane, γ-Methacryloxypropyl trimethoxy silane and vinyl trimethoxy silane is a suitable method to improve the performance in terms of mechanical and thermally. Silane forms covalent bonds with starch during starch modification resulted in enhanced shear strength and storage stability. A new research on biodegradable, renewable, environmentally friendly silane modification of starch-based wood adhesive that was prepared by reacting with various silanes. This paper, we reviewed silane as a modifying agent for starch-based wood adhesive.
基金This work was supported by the China Postdoctoral Science Foundation(China Fund[1998]6)that was entitled“Synthesis of Modified Starch Binder and Its Application in Foundry”.Authors would like to thank academician Jinzong YANG and lecturer Hua ZHANG for the kind analyses and discussions.
文摘Interactions between different components in α-starch based composite binder for green sand mould/core were investigated by using XRD, IR spectra, 1H NMR spectra and SEM. Several adhesive hardening structures and theories of the binder at room temperature were proposed according to the interactions between various compositions. Thus, the reasons for the binder to have excellent combination properties and unique adhesive bonding and self-curing characteristics were explained by these theories successfully. And the theories are of great directive importance to design and development of composite binder for green sand mould/core.
基金This work was supported by the Fundamental Research Funds for the Central Universities(Y0201800586)the Regional Cooperative Innovation in Autonomous Region(2019E0241).
文摘With the exponential growth of the computing power,machine learning techniques have been successully used in various applications.This paper intended to predict and optimize the shear strength of single lap cassava starch-based adhesive joints for comparison with the application of artificial intelligence(AI)methods.The shear strength was firstly determined by the experiment with three independent experimental variables(starch content,NaOH concentration and reaction temperature).The analysis of range(ANORA)and analysis of variance(ANOVA)were applied to investigate the optimal combination and the significance of each factor for the shear strength based on the orthogonal experiment.The performance of all AI models was char acterized by mean absolute error(MAE),root mean square error(RMSE)and regression coefficient(R^(2))compared with the experi-mental ones.The GA optimized ANN model was combined with the genetic algorithm(GA)to find the optimal combination of factors for the finalized optimized cassava starch adhesives(CSA-OP).The physicochemical prop-erties of the cassava starch and CSA-OP were determined by the FTIR,TGA and SEM EDS,respectively.The results showed that the numerical optimized condition of the GA optimized ANN model was superior to the orthogonal experimental optimized condition.The sensitivity analysis revealed that the relative importance of variables was consistent with the results from ANOVA.FTIR results showed that there were high hydroxyl groups in cassava starch.TGA results showed that the residue of CSA OP was higher than the assava starch.SEM EDS results showed that both the cassava starch and CSA OP had abundant carbon and oxygen functional groups.Consequently,the obtained results revealed that the use of AI methods was an adequate approach to model and optimize the experimental variables of the shear strength of single lap cassava starch-based adhesive joints.
文摘Bio-degradable cassava starch-based adhesives were produced from chemically gelatinized starch formulations. The varying combinations of process parameters applied include: concentration of gelatinization modifier, mass % borax/starch, and temperature of reaction mixture. The physico-chemical parameters for characterizing the adhesive samples were viscosity, density, pH and bonding strength. The effects of the variation of process parameters on the quality of the adhesives were assessed using response surface (central composite) designs with 2 factors, to relate the highest adhesive quality with the optimal combination of process factors. The adhesives produced using HCl as the gelatinization modifier were of a higher quality than those produced using NaOH with one of the most important quality assessment parameters which is the bond strength being 22.31 kPa at 0.01 M and 20% mass borax/starch and 11.60 kPa at 0.01 M and 8% mass borax/starch for HCl and NaOH respectively. The experimental results demonstrated that the optimal temperature for the production of the adhesive was 85˚C.
基金the Fund of Anhui Province Science Research Projects,China(No.1106b0105062)the Research Foundation Program of Scientific and Technological Innovation Team of College and University at the Provincial Level of Anhui,China(No.TD200710)
文摘A series of dodecenylsuccinylated starches( DSSs) with different degree of substitution( DS) were prepared via the esterification of dodencenylsuccinic anhydride with hydrolyzed cornstarch in aqueous dispersion for investigating the influences of starch dodecenylsuccinylation upon the performances such as apparent viscosity and surface tension of starch paste, film behaviors,and adhesion to fibers for warp sizing. It was found that the dodecenylsuccinylation was able to reduce the surface tension of cooked starch paste and enhance the adhesion of starch to polyester fibers. It was also capable of depressing the brittleness of native starch and improving the mechanical behaviours such as breaking elongation and work-to-break of starch film. Initial increase in DS level of dodecenylsuccinylation enhanced these positive effects,while excessively increasing the level resulted in marked reduction in tensile strength of starch film and significant decrement in reaction efficiency. X-ray diffraction patterns of starch films showed the dodecenylsuccinates derivatized onto the backbones of starch depressed the degree of crystallinity of starch film. Based on the paste behaviors, adhesion, and film properties, the dodecenylsuccinylation level is recommended in a range of 0. 015-0. 025 for sizing polyester warps.
基金The Foundation for the Talents by Anhui Province,China(No.2002Z036)
文摘Influences of some electrolyte impurities within starch and starch cationization on the adhesion of quaternary ammonium cornstarch to cotton and polyester fibers were investigated. The electrolytes considered included NaCI, Na2SO4, NaH2PO4 and Na2HPO4. The adhesion to fibers was evaluated in terms of maximum strength and work-to-break of the roving sized with the starch pastes containing electrolytes. It was found that the cationization showed a positive effect on the adhesion to both fibers whereas the electrolytes gave an adverse effect and reduced the adhesion. The adverse effect depends on the type and amount of electrolytes. The influence of electrolytes on the adhesion can be ranked in a series of NaH2PO4〉 Na2 HPO4〉 Na2SO4 〉 NaCl. The adhesion enhances as the modification extent increases and the electrolyte content decreases. Furthermore, the adverse effect can be compensated by the positive effect of the starch modification even at a low modification extent. If the electrolytes are fully eliminated, the cationic starch can increase the adhesion strength by more than 10% for both fibers.
文摘Hot-melt (HM) adhesives offer advantages over their contemporary water-based and solvent-based adhesives like low volatile organic compounds (VOCs), 100% solid, fast drying, setting etc. In recent years, to reduce their dependence on dwindling petroleum resources and due to the enormous use of HM adhesives in packaging areas that demand 100% recyclability, efforts have been devoted to making these formulations completely bio-based, sustainable and biodegradable. In this attempt, research and developments have been focused on using starch, modified starch, soy protein, polylactides, polyamides, lignin and vegetable oils as a partial/fully replacement to the petrochemical</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">based polymers. The huge amount of research going on in the field of bio-based polymers has still not reached its complete potential in the field of HM adhesives. In this review paper</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> HM adhesives based on sustainable raw materials namely starch, modified starch, polyamides, poly (lactic acid), soy protein and lignin are discussed.
