共查询到19条相似文献,搜索用时 406 毫秒
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研究了碱处理、尿素改性、碱和尿素联合改性以及淀粉基胶粘剂共混对棉籽粉基胶粘剂理化性质及物理力学性能的影响。研究结果表明:改性方法对棉籽粉基胶粘剂干状胶合强度(≥4.0 MPa)无明显影响,并且碱和尿素联合改性可以将棉籽粉基胶粘剂的黏度从51.0 mPa·s提高至128.5 mPa·s。而使用高黏度淀粉基胶粘剂与棉籽粉基胶粘剂共混制得的复合胶粘剂的黏度高于530 mPa·s;尿素对棉籽粉中的棉蛋白具有一定的活化作用,淀粉基胶粘剂并未对棉籽粉化学官能团产生影响;获得的棉籽粉基胶粘剂符合人造板生产工艺要求,为其工业化利用提供支持。 相似文献
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Xiaoqun Mo & Xiuzhi Susan Sun 《Journal of Adhesion Science and Technology》2013,27(18-19):2014-2026
Soybean proteins have great potential as bio-based adhesives. The objectives of our study were to develop and characterize formaldehyde-free soybean wood adhesives with improved water resistance. Second-order response surface regression models were used to determine the effects of soy protein isolate concentration, sodium chloride, and pH on adhesive performance. All three variables affected both dry and wet strengths of bonded wood specimens. The optimum operation zone for preparing adhesives with improved water resistance is at a protein concentration of 28% and pH 5.5. Sodium chloride had negative effects on adhesive performance. Soy adhesives modified with 0.5% sodium chloride had dry strength, wet strength, and boiling strength of bonded specimens comparable to nonmodified soy adhesives. Rheological study indicated that soy adhesives exhibited shear thinning behavior. Adhesives modified with sodium chloride showed significantly lower viscosity and yield stress. Sodium chloride-modified soy adhesives formed small aggregates and had low storage moduli, suggesting reduced protein–protein interactions. These formaldehyde-free soy adhesives showed strong potential as alternatives to commercial formaldehyde-based wood adhesives. 相似文献
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Soy protein adhesives have great potential as sustainable eco-friendly adhesives. However, low adhesion under wet conditions hinders its applications. The objective of this research was to enhance the water resistance of soy protein adhesives. The focus of this research was to understand the effect of protein to lignin ratio and lignin particle size i.e. large (35.66 μm), medium (19.13 μm), and small (10.26 μm) on the adhesion performance of soy protein adhesives as well as to characterize its rheological and thermal properties. Results showed that the lignin particle size and the protein to lignin ratio greatly affected the adhesion performance of soy protein adhesives. The addition of lignin slightly increased the viscosity, spreadability, and thermostability of soy protein adhesives. The wet strength of soy protein adhesives increased as lignin particle size decreased. Soy protein mixed with small size lignin at a protein to lignin ratio of 10:2 (w/w) at 12% concentration presented the lowest contact angle and the highest wet adhesion strength of 4.66 MPa., which is 53.3% higher than that of 10% pure soy protein adhesive. The improvements in adhesion performance and physicochemical properties of soy protein adhesives by lignin were ascribed to the interactions between protein and lignin. Lignin with smaller particle size increased the wet shear strength of soy protein adhesives because a larger surface area of lignin was available to interact with the protein. 相似文献
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Physicochemical Properties of Soy Protein Adhesives Obtained by In Situ Sodium Bisulfite Modification During Acid Precipitation 总被引:1,自引:0,他引:1
Guangyan Qi Ningbo Li Donghai Wang Xiuzhi Susan Sun 《Journal of the American Oil Chemists' Society》2012,89(2):301-312
Successful industrial applications of soy protein adhesives require high adhesion strength and low viscosity at high solid
protein concentration. This study examined the effects of β-conglycinin (7S) and glycinin (11S) ratios on the physicochemical
properties of soy protein adhesives. Soy protein adhesives with various 7S/11S ratios were extracted from soy flour slurry
modified with sodium bisulfite using the acid precipitation method, which is based on the different solubilities of 7S and
11S globulins. Seven glycinin-rich soy protein fractions and six β-conglycinin-rich soy protein fractions were obtained. The
external morphology of the samples changed from the viscous cohesive phase to the clay-like phase without cohesiveness. The
viscous cohesive samples had good flowability and good water resistance with a wet adhesion strength of 2.0–2.8 MPa. They
were stable for up to several months without phase separation at room temperature. Based on the results, we suggest that proper
protein–protein interaction, hydration capacity (glycinin-rich soy protein fractions), and certain ratios of 7S and 11S (β-conglycinin
rich soy protein fractions) in the soy protein sample are crucial to continuous protein phase formation. Hydrogen bonding,
electrostatic forces, and hydrophobic interactions are involved in maintaining the protein viscous cohesive network, whereas
disulfide bonds do not exert significant effects. This study describes a new way to investigate viscous cohesive soy protein
systems with high solid protein content, thus alleviating the disadvantages of traditional methods for studying the adhesive
properties of soy protein isolates, which tend to have poor water resistance, low solid contents, and short storage life. 相似文献
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Doroteja Vnučec Andreja Kutnar Andreja Goršek 《Journal of Adhesion Science and Technology》2013,27(8):910-931
Over recent years, the interest in bio-adhesives, including soy-based adhesives, has increased rapidly. Among natural renewable resources suitable for industrial use, soy is a reasonable choice due to its high production volume and the small use of soy meal-based products for human food consumption. Soy flour can be an ideal raw material for the manufacturing of wood adhesives due to its low cost, high protein content and easy processing. There are also more concentrated forms of soy proteins, i.e. concentrates and isolates, which are also suitable raw materials for adhesive production except that their prices are higher. Extensive research has been carried out on improving the cohesive properties, especially water resistance, of soy-based adhesives. However, there is insufficient experimental data available for understanding the influences of modification methods on the structure of soy proteins and therefore for understanding the influences of structural changes on the adhesion. In this paper, some experimental techniques are proposed to be used for analysing soy-based adhesives to enable better understanding of those factors and improve future development. This review of soy-based adhesives is made with the focus on soy proteins’ chemical composition, soy protein product types (raw materials for adhesive production), modification methods for improving the adhesive properties of soy-based adhesives, and commercial soy-based adhesives. 相似文献
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Development of High-Strength Soy Protein Adhesives Modified with Sodium Montmorillonite Clay 下载免费PDF全文
Guangyan Qi Ningbo Li Donghai Wang Xiuzhi Susan Sun 《Journal of the American Oil Chemists' Society》2016,93(11):1509-1517
This study investigated the high strength of a soy protein adhesive system with good flowability at high protein concentration. Sodium montmorillonite (Na MMT), the most widely used silicate clay, was incorporated into viscous, cohesive soy protein adhesives at concentrations ranging from 1 to 11 % (dry basis, w/w). Hydroxyethyl cellulose was used as a suspension agent to stabilize the soy protein and nano clay to be the dispersion system. The interaction between soy protein and Na MMT was characterized by XRD, FTIR, Zeta potential and DSC. Results indicated that soy protein molecules were adsorbed on the surface of the interlayer of Na MMT through hydrogen bonding and electrostatic interaction. The soy protein/Na MMT adhesives had the intercalation structure with Na MMT contents ranging from 1 to 11 %. Adhesion strength, specifically wet adhesion strength, of soy protein adhesives at isoelectric point (pI) was significantly improved by the addition of Na MMT. It is believed that the physical cross‐linking reactions between soy protein and Na MMT mainly contribute to the improved adhesion performance of soy protein adhesives. Wet adhesion strength increased from 2.9 MPa of control soy protein adhesive to 4.3 MPa at 8 % Na MMT. An increase of pH beyond pI value resulted in decreased adhesion strength due to increased surface charges of soy protein and slightly reduced affinity of soy protein on the nano clay surface. 相似文献
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Guangyan Qi Ningbo Li Donghai Wang Xiuzhi Susan Sun 《Journal of the American Oil Chemists' Society》2013,90(12):1917-1926
Soy protein adhesives with a high solid content (28–39 %) were extracted from soy flour slurry modified with sodium bisulfite (NaHSO3) at different concentrations. 11S‐dominated soy protein fractions (SP 5.4) and 7S‐dominated soy protein fractions (SP 4.5) were precipitated at pH 5.4 and pH 4.5, respectively. The objective of this work was to study the effects of NaHSO3 on adhesion and physicochemical properties of soy protein. The adhesion performance of NaHSO3‐modified SP 4.5 was better than SP 5.4; the wet strength of these two fractions was from 2.5 to 3.2 MPa compared with 1.6 MPa of control soy protein isolate. SDS‐PAGE results revealed the reducing effects of NaHSO3 on soy protein. The isoelectric pH of soy protein decreased as NaHSO3 increased due to the induced extra negative charges (RS‐SO3?) on the protein surface. The rheological properties of soy protein adhesives were improved significantly. Unmodified samples SP 5.4 and SP 4.5 had clay‐like properties and extremely high viscosity, respectively; with 2–8 g/L NaHSO3 modification, both SP 5.4 and SP 4.5 had a viscous cohesive phase with good flowability. Overall, NaHSO3‐modified soy protein adhesives in our study have many advantages over the traditional soy protein isolate adhesive such as better adhesion performance, higher solid content but with good flowability and longer shelf life. 相似文献
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Christopher G. Hunt Linda F. Lorenz Carl J. Houtman Eder Valle Thomas Coolidge Chera Mock Charles R. Frihart 《Journal of the American Oil Chemists' Society》2023,100(1):69-79
The impact of jet cooking on shear strength of soy-and-water adhesives was investigated to understand the higher shear strength of commercial soy protein isolates compared to soy flours. Soy flour-based wood adhesives are appealing because of their bio-based content, low formaldehyde emission, and low cost, but their commercial application is limited by low wet cohesive strength. Previous researchers proposed that the process of jet cooking (steam injection with high turbulence followed by rapid cooling) was responsible for the high (~3 MPa) wet shear strength of adhesives made with commercially produced soy protein isolate, using the ASTM D 7998 test. In this work, we show that jet cooking did dramatically increase the wet strength of laboratory-produced, native-state soy protein isolate from 0.6 to 3 MPa, a strength similar to many commercial isolates. Jet cooking was far less effective at developing wet strength of soy flours, but greatly increased the viscosity of virtually all our soy materials. We hypothesize that the benefits of jet cooking are primarily a result of nonequilibrium protein aggregation states because subsequent wet autoclaving of jet cooked soy proteins dramatically decreased wet strength. The dramatic differences in adhesive properties between commercial soy protein isolates and soy flours suggests that the common practice of using results obtained with commercial isolates to predict the performance of soy flour adhesives is inappropriate. 相似文献
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Correlation between Physical Properties and Shear Adhesion Strength of Enzymatically Modified Soy Protein-Based Adhesives 下载免费PDF全文
Min Jung Kim Xiuzhi Susan Sun 《Journal of the American Oil Chemists' Society》2015,92(11-12):1689-1700
This work was to correlate physical properties with adhesion properties of soy protein‐based adhesives. By building such a correlation, the adhesion properties can be predicted by measuring physical properties of soy protein‐based adhesives. In this context, three important physical properties, viscosity, tacky force, and water resistance, were selected to correlate with adhesion strength of enzymatically modified soy protein‐based adhesives (ESP). Response surface methodology, specifically central composite design, was used with three independent variables to prepare ESP: trypsin concentration (X1), incubation time (X2), and glutaraldehyde (GA) concentration (X3). The three physical properties measured were all greatly affected by our three independent variables with significance at the 95 % confidence level. The responses were then correlated with the adhesion properties of ESP. In conclusion, viscosity can be used to predict the dry adhesion strength of ESP based on the coefficient of determination (R2) of 0.8558. In addition, tacky force and water resistance can be used to represent wet adhesion strength of ESP based on R2 of 0.7082 and 0.6930, respectively (P < 0.05). This work preliminarily identified the significant physical properties that can predict the adhesion strength of the ESP system crosslinked with GA, but the results need to be further confirmed by another protein modification system to give a generic conclusion. 相似文献