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1.
Milagros P. Hojilla-Evangelista Larson B. Dunn Jr. 《Journal of the American Oil Chemists' Society》2001,78(6):567-572
A study was conducted to evaluate the potential of soy protein-based plywood glues for foam extrusion. Foaming properties
were the first criterion used to screen several soy protein sources. Foaming capacities and stabilities of glue mixes containing
animal blood (control) or soy products (meals, flours, concentrates, and isolates) were compared and correlated with molecular
weights and surface hydrophobicity indices (S
o) in an attempt to identify structure/function relationships. The blood-based glue mix produced more foam than any of the
soy-based glues. Soy flours and concentrates generally produced greater foam volumes and more stable foams than soy meal and
isolates. Differences in foaming properties could not be explained by solubility profiles or S
o. However, results of gel electrophoresis indicated that soy products with poor foaming properties had extensive structure
modifications or contained considerably lesser amounts of protein available for foaming reactions. Glue mixes containing the
soy flours ISU-CCUR, Honeysoy 90, Nutrisoy 7B, and defatted Soyafluff and the soy concentrates Arcon F, ISU-CCUR, and Procon
2000 demonstrated the desired mixing and foaming properties for foam extrusion. 相似文献
2.
In Yang Monlin Kuo Deland J. Myers 《Journal of the American Oil Chemists' Society》2006,83(3):231-237
Increased demand for wood adhesives, environmental concerns, and the uncertainty of continuing availability of petrochemicals
have led to recent attention on protein-based adhesives. This study was conducted to investigate the glue bond qualities of
soy-based phenolic adhesive resins for southern pine plywood. Two types of soy-based resins were formulated and tested. The
first was made by cross-linking soy flour with phenol-formaldehyde (pf) resins at neutral pH. The second type was obtained
by cross-linking soy flour hydrolyzates with pf resin under alkaline conditions. Plywood bonded with the neutral phenolic
soy resins containing 70% soy flour and 30% 1.6 g/cm2 pf without the use of extenders and fillers compared favorably with the traditional southern pine pf glue mixes. Plywood
bonded with alkaline phenolic soy resins, containing 40 or 50% 0.5 g/cm2 PF with the addition of extender (19% corn-cob powder), provided better adhesive glue bond properties than traditional southern
pine pf glue mixes. These results suggest that soy-based phenolic adhesive resins have potential for the production of exterior
southern pine plywood. 相似文献
3.
通过对大豆粉采用碱处理使大豆蛋白质大分子结构展开,暴露出的官能团进一步与甲醛反应生成稳定的蛋白质,这种物质与苯酚共聚反应生成改性豆基蛋白胶黏剂。采用单因素实验方法,探讨了改性豆基蛋白胶黏剂压制杨木三层胶合板的胶合工艺。分析了热压温度、热压时间和涂胶量对胶合板胶合性能的影响。结果表明:采用改性后的豆基蛋白胶黏剂,在压力为1.4MPa,温度为165℃左右,热压时间为1.4~1.6min·mm^-1,涂胶量为220g·m^-2,压制的杨木胶合板胶合性能较佳且达到Ⅰ类胶合板的标准。 相似文献
4.
Shear strength and water resistance of modified soy protein adhesives 总被引:32,自引:0,他引:32
Soy protein polymers recently have been considered as alternatives to petroleum polymers to ease environmental pollution.
The use of soy proteins as adhesives for plywood has been limited because of their low water resistance. The objective of
this research was to test the water resistance of adhesives containing modified soy proteins in walnut, maple, poplar, and
pine plywood applications. Gluing strength and water resistance of wood were tested by using two ASTM standard methods. Glues
with modified soy proteins had stronger bond strength than those containing unmodified soy proteins. Plywood made with glue
containing urea-modified proteins had higher water resistance than those bonded with glues containing alkali-modified and
heat-treated proteins. After three 48-h cycles of water-soaking, followed by 48 h of air-drying, no delamination was observed
for either walnut or pine specimens glued with the urea-modified soy protein adhesives. Gluing strength for wood species with
smooth and oriented surface structure was lower than for those with rough, randomly oriented, surface structures. Wood species
with greater expansion of dimensions during water-soaking had a higher delamination rate than those showing less expansion. 相似文献
5.
J. J. Rackis J. E. Mcgee M. R. Gumbmann A. N. Booth 《Journal of the American Oil Chemists' Society》1979,56(3):162-168
Pancreatic hypertrophy that occurs in rats fed raw soy flour containing about 1200 mg tripsin inhibitor (TI)/100 g diet was
reversed by switching the rats to control diets or to diets containing 30% toasted defatted soy flour. No pancreatic hypertrophy
occurs in rats fed commercial, edible grade soy flours, concentrate or isolate from time of weaning to adulthood (ca. 300
days). TI content of the soy diets ranged from 178–420 mg/100 g. Except for pancreas enlargement in rats fed raw soy flour,
gross and microscopic examination of pancreata revealed no abnormalities. The gross appearance of heart, kidney, spleen, and
liver was normal. Soy flour, protein concentrate, and protein isolate in a formulated corn-soy diet provided optimum growth
and maintained body weight only if supplemented with vitamin B-12 in long term feeding studies with rats. In the absence of
such supplementation, rats fed soy diets initially grew at a rate equal to or greater than those fed a comparable corn-casein
control diet; but, with continued feeding for ca. 300 days, body weight of rats fed the casein control was significantly greater
than that of the soy flour-fed rats. Those fed soy isolate ceased to grow; and rats fed soy concentrate lost weight. No significant
differences were found in organ weights between groups fed soy products and casein, except for increased kidney, liver, and
testes weights relative to body weight with the group fed soy concentrate. Supplementation of the soy diets with vitamin B12 stimulated growth to the greatest extent, calcium pantothenate or riboflavin had an intermediate effect, other vitamins had
little or no effect; whereas a complete mineral mix was detrimental. Supplementation of the soy diets with vitamin B12 stimulated growth to the greatest extent, calcium pantothenate or roboflavin had an intermediate effect, other vitamins had
little or no effect; whereas a complete mineral mix was detrimental. Supplementation of the control diet was without effect.
The dietary protein level in these diets was 20%, with casein or soy protein representing 75% of total protein. When fed continuously
to rats from weaning to adulthood, properly processed soy protein products, when balanced with essential nutrients, can provide
growth comparable to corn-casein diets. 相似文献
6.
Mila P. Hojilla-Evangelista 《Journal of the American Oil Chemists' Society》2010,87(9):1047-1052
This study was conducted to evaluate the performance of soybean meal as a protein extender in plywood adhesive intended for
sprayline coaters. Ground soybean meal, with 52.8% (dry basis, db) crude protein and 0.9% (db) residual oil, replaced the
current industry extender, wheat flour, in the standard glue mix. Substitution was done on the protein content basis. Mixing
and adhesion properties of the glue containing soybean meal were compared with those of the industry-standard glue. The soybean
meal-based glue showed excellent mixing characteristics and its viscosity (1,275 cp) met the recommended value for this type
of adhesive. Its wet tensile strength, however, was less than that of the standard glue and below the threshold value of 200
psi considered as an indicator of strong bonding. The soybean meal glue formulation was then modified further by increasing
the amount of meal such that the amount of protein present was double that contributed by wheat flour in the original mix.
This adjustment resulted in higher wet tensile strength (209 psi), which not only met the threshold value for strong glue
bonds, but also equaled that of the standard glue. These results demonstrated that soybean meal is a viable extender in plywood
glue for sprayline coaters. 相似文献
7.
Jane L. O’Dell Charles R. Frihart 《Journal of Adhesion Science and Technology》2013,27(18-19):2027-2042
We studied the high temperature performance of soy meal processed to different protein concentrations (flour, concentrate, and isolate), as well as formulated soy-based adhesives, and commercial nonsoy adhesives for comparison. No thermal transitions were seen in phenol-resorcinol-formaldehyde (PRF) or soy-phenol-formaldehyde (SoyPF) or in as-received soy flour adhesive during differential scanning calorimetry scans heating at 10?°C/min between 35 and 235?°C. Heat flow rates decreased in the order soy flour (as received)?>?SoyPF?>?PRF?>?emulsion polymer isocyanate (EPI). In thermogravimetric analysis (TGA) scans from 110 to 300?°C at 2?°C/min, total weight loss decreased in the order soy flour (as-received)>SoyPF?>?PRF?>?casein?>?maple?>?EPI. For bio-based materials, the total weight loss (TGA) decreased in the order soy flour (as-received) > concentrate, casein?>?isolate. Dynamic mechanical analysis from 35 to 235?°C at 5?°C/min of two veneers bonded by cured adhesive showed 30–40% decline in storage modulus for maple compared to 45–55% for the adhesive made from soy flour in water (Soy Flour) and 70–80% for a commercial poly(vinyl acetate) modified for heat resistance. DMA on glass fiber mats showed thermal softening temperatures increasing in the order Soy Flour?<?casein?<?isolate?<?concentrate. We suggest that the low molecular weight carbohydrates plasticize the flour product. When soy-based adhesives were tested in real bondlines in DMA and creep tests in shear, they showed less decrease in storage modulus than the glass fiber-supported specimens. This suggests that interaction with the wood substrate improved the heat resistance property of the adhesive. Average hot shear strengths (ASTM D7247) were 4.6 and 3.1?MPa for SoyPF and Soy Flour compared to 4.7 and 0.8?MPa for PRF and EPI and 4.7 for solid maple. As a whole, these data suggest that despite indications of heat sensitivity when tested neat, soy-based adhesives are likely to pass the heat resistance criterion required for structural adhesives. 相似文献
8.
Charles R. Frihart Holly Satori 《Journal of Adhesion Science and Technology》2013,27(18-19):2043-2052
Soy flour adhesives using polyamidoamine-epichlorohydrin (PAE) resin as the curing agent are being used commercially to make bonded wood products. The original studies on the soy-PAE adhesives used purified soy protein isolate, but the much lower cost soy flour is now used commercially. We examined the performance of commercially available soy flours that have their proteins either mainly in their native (90 protein dispersibility index (PDI)) or denatured (70 and 20 PDI) states. We expected that the more native state soy proteins with their better dispersibility would provide better adhesion to wood surfaces and enhanced reaction with PAE resin. Small-scale wood bonding tests showed that neither of these effects was observed without and with a low level of PAE. In these tests, the solids content of the soy formulations had a large influence on adhesive viscosity but little influence on bond strength. Additionally, little difference was observed in any of the adhesive or viscosity properties between the soy flours having either a 0.152 or 0.075?mm (100 or 200 mesh) particle size. 相似文献
9.
Saman Ghahri Antonio Pizzi Behbood Mohebby Ahmad Mirshokraie Hamid Reza Mansouri 《The Journal of Adhesion》2018,94(3):218-237
In this research, two different types of commercial tannins, namely a hydrolysable tannin (chestnut) and a condensed flavonoid tannin (mimosa), were used to prepare two types of soy-based (soy flour (SF) and soy protein isolate) adhesives for making plywood. Thermogravimetric properties (TGA) and its derivative as function of temperature (DTG) of different soy-based adhesive were measured in the range 40°C–300°C. Thermomechanical analysis (TMA) from 25°C to 250°C was done for the different resin formulations. Duplicate three-ply laboratory plywood panels were prepared by adding 300 g/m2 of the adhesives’ total resin solid content composed of SF or isolated soy protein (ISP), urea, chestnut, and mimosa tannin extracts with hexamine as hardener. Based on the results obtained, tannins can improve SF adhesion properties. The TMA showed that chestnut tannin extract appeared to react well with SF, while mimosa tannin extract appeared to react well with ISP. Matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry also showed that among other reactions, the soy protein amino acids reacted with the tannins. Furthermore, delamination and shear strength test results showed the good water resistance of plywood bonded with soy-based tannin modified adhesive. 相似文献
10.
大豆7S与11S球蛋白尿素变性后的粘接性质研究 总被引:2,自引:0,他引:2
随着人们对环境保护意识的增加和地球有限资源的缺乏,大豆蛋白在胶粘剂工业中的应用也越来越显示出强大的吸引力,鉴于前人的研究成果,文章研究了大豆7S和11S球蛋白经过尿素变性后在松木、樱桃木和胡桃木上的粘接强度和湿润能力。结果表明在不同的木块上不同胶粘剂有不同的粘接强度和湿润性能。7S大豆蛋白尿素变性后在硬木上有较好的湿润性。1M尿素变性赋予11S蛋白的粘接强度最高,3M尿素变性后,7S蛋白在硬木上的粘接强度大于11S蛋白。蛋白质的二级结构测量表明β-折叠对于3 M尿素变性后的大豆蛋白在硬木上的粘接强度起着重要作用,而无规则卷曲是降低1 M尿素变性7S大豆蛋白粘接强度的主要因素。 相似文献
11.
Mahsa Barzegar Rabi Behrooz Hamid Reza Mansouri Saeed Kazemi Najafi Linda F. Lorenz Charles R. Frihart 《Journal of the American Oil Chemists' Society》2020,97(12):1371-1383
Canola is widely grown in the northern latitudes for its vegetable oil, generating large quantities of residual, low value canola flour used as animal feed. The common wood adhesive poly(diphenylmethylene diisocyanate) (pMDI) should react with the wide variety of functional groups in proteins. Therefore, it would seem that canola flour with added pMDI could be an effective adhesive. Two main questions are addressed in this study: How do the wood adhesive properties of canola flour compare to the better-studied soy flour? How well do proteins, which contain an abundance of functional groups, cure with the very reactive pMDI? These questions were addressed using the small-scale adhesive strength test ASTM D-7998, with various adhesive formulations and bonding conditions for canola flour plus pMDI compared to soy adhesives. The more challenging wet cohesive bond strength was emphasized because the dry strengths were usually very good. Generally, soy adhesives were better than canola ones, as was the polyamidoamine-epichlorohydrin cross-linker compared to pMDI, but these generalizations can be altered by the conditions selected. Three-ply plywood tests supported the small-scale test results. 相似文献
12.
Enzymatic modification of soy protein concentrates by fungal and bacterial proteases 总被引:9,自引:0,他引:9
L. S. Bernardi Don A. M. R. Pilosof G. B. Bartholomai 《Journal of the American Oil Chemists' Society》1991,68(2):102-105
Solubility, foaming capacity and foam stability of denatured soy protein concentrate obtained from toasted flour were improved
by proteolysis with fungal or bacterial proteases. Emulsifying capacity was unchanged, but emulsion stability decreased; bacterial
protease highly improved oil absorption. Also, the bacterial protease was able to solubilize more protein and gave products
which foamed more than those obtained with the fungal enzyme. However, the stabilizing properties of the bacterial modified
soy protein concentrate at the air/water or oil/water interface were inferior. By limited hydrolysis up to degree of hydrolysis
10% most functional properties were improved without greatly reducing emulsion stability and water absorption. 相似文献
13.
Chromatographic Analysis of the Reaction of Soy Flour with Formaldehyde and Phenol for Wood Adhesives 总被引:2,自引:0,他引:2
Linda Lorenz Charles R. Frihart James M. Wescott 《Journal of the American Oil Chemists' Society》2007,84(8):769-776
The desire to make more biobased and lower-cost bonded wood products has led to an interest in replacing some phenol and formaldehyde
in wood adhesives with soybean flour. Improved knowledge of the soy protein properties is needed to relate resin chemistry
to resin performance before and after wood bonding. To expose the soy protein’s functional groups, it needs to be disrupted,
with minimal hydrolysis, to maximize its incorporation into the final polymerized adhesive lattice. The best conditions for
alkali soy protein disruption were to maintain the temperature below 100 °C and react the soy flour with sodium hydroxide
at pH 9–12 for about 1 hour. A gel permeation chromatography procedure was optimized to determine conditions for selectively
breaking down the high molecular weight soy protein fragments that contribute to high adhesive viscosity. This method and
extraction data were used to evaluate the reaction of the disrupted soy flour protein with formaldehyde and phenol to provide
a stable adhesive. The results were used to develop more economical adhesives that are ideally suited for the face section
of oriented strandboard. 相似文献
14.
Tadeusz Jakubczyk Hanna Haberowa 《Journal of the American Oil Chemists' Society》1974,51(1):120A-122A
Effect of soy flour, soy protein concentrate, and isolate on dough and loaf properties of breads produced from flour, yeast,
salt, and water with no shortening or added improvers was investigated. Wheat flour, rye flour, and mixtures of the two were
included in the studies. Three wheat flours, varying in baking quality and extraction, ash content 0.65 and 0.80%, were used;
1.5, 3, and 5% soy products, flour basis, were added. Water absorption increased 3.8–4.7% at the 3% soy level and 6.1–7.3%
at the 5% level of soy product addition. Dough development time and stability were increased and dough softening reduced.
Dough gassing power increased ca. 7–25%. By using a shorter proofing time, more intensive mixing, and the sponge dough process,
loaves only slightly smaller in volume than the control were obtained at the 3% soy level. Panel evaluations scored bread
highest with 1.5 or 3% soy flour and that with 3 or 5% soy protein concentrate as lowest, but acceptable. Use of 2% lard as
shortening, or 2% lard plus emulsifier, produced soy breads of excellent quality and ca. 25% higher loaf volume than controls. 相似文献
15.
Sang K. Park N. S. Hettiarachchy 《Journal of the American Oil Chemists' Society》1999,76(10):1201-1205
Flexible plastic foams using soy protein isolate (SPI), soy protein concentrate (SPC), and defatted soy flour (DFS) were produced
by interacting proteins with glycerol-propylene oxide polyether triol (polyol), surfactant, triethanolamine (crosslinking
agents), tertiary amine (catalyst), and water (blowing agent). The density, compressive stress, resilience, and dimensional
stability of foams with SPI, SPC, and DFS increased as the initial concentration of soy protein increased. The foam density
increased with increasing weight percentage of SPI, SPC, and DFS. The resilience values of SPI containing foam increased with
the increasing addition of SPI up to a maximum 30% SPI addition. An increase in SPI up to 20% caused an increase in the compressive
stress (225 kPa) in comparison to control polyurethane foam (187 kPa). The control foam and foam containing 20% DFS had a
similar load-deformation relationship. The foam containing 20% SPI and SPC also exhibited a similar shape, but with a higher
compressive stress. The compressive stress of all foams was steeply increased after 55% strain, since the foams completely
collapsed upon compression. 相似文献
16.
The compatibilizing effect of anhydride groups attached to a polyester was examined while blending soy protein and a biodegradable polyester. Three different polyesters grafted with anhydride functional groups were used as compatibilizers for blending with soy protein concentrate, soy flour, and soy isolate. The processing conditions for these blends in a twin screw extruder and injection‐molding machine were evaluated and the physical and mechanical properties of these blends were determined. The concentrations of soy protein and compatibilizer were varied to achieve optimum mechanical properties, exploring the various limits of operating conditions. The dynamic mechanical properties were determined using a rheometric mechanical spectrometer (RMS‐800). The enthalpy of fusion was determined using a differential scanning calorimeter. Blends containing compatibilizer gave enhanced tensile strength when compared to blends without compatibilizer. The morphology of these blends was investigated with the help of an optical microscope and X‐ray diffraction was used for crystallinity studies. Water and oil absorption by these blends were determined for a period of 25 days. © 1999 Society of Chemical Industry 相似文献
17.
A. Salvini L. M. Saija S. Finocchiaro G. Gianni C. Giannelli G. Tondi 《应用聚合物科学杂志》2009,114(6):3841-3854
The role of the main components of a PVAc‐based wood adhesive formulation in the formation and performance of the adhesive joint was investigated. A new analytical methodology was applied to carry out the chemical separation and characterization of the adhesive components present in the bond line. By using extraction techniques on the wet and dry glues it was possible to observe the variation in the solubility of the adhesive components, for different glue formulations. The swollen‐state NMR technique proved to be a very useful tool to characterize the insoluble parts present in the adhesive films. These findings, when put into relation to some specific properties of the adhesive joints, contribute to the understanding of the mechanisms involved in the adhesion process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
18.
Soy proteins have shown great potential for adhesive and resin applications. This investigation characterized the thermal
and adhesive properties of the major soy protein components conglycinin (7S) and glycinin (11S) after chemical modification.
These globulins were extracted from defatted soy flour, then modified with either sodium hydroxide, sodium dodecyl sulfate
(SDS), or urea. Modified 7S, 11S, and mixtures of 7S and 11S at varying ratios were evaluated for gluing strength with cherry
veneer plywood and for thermal denaturation using DSC. Adhesive strength and water resistance were significantly improved
for all proteins modified with sodium hydroxide. Gluing strength and water resistance were improved for SDS- and ureamodified
proteins containing greater portions of 7S globulins. The opposite behavior was observed for proteins containing large amounts
of 11S globulins. DSC results showed that the temperatures of denaturation (T
d
) decreased for the proteins modified with sodium hydroxide or urea, whereas the T
d
values of proteins modified with SDS were similar to the unmodified proteins. These results suggested that, at the concentrations
studied, sodium hydroxide or urea could denature soybean protein more effectively than SDS, resulting in lower protein thermal
stability. Soybean proteins with high ratios of 11S had more ordered structures, as evidenced by the high enthalpy values
of protein denaturation observed in DSC measurements. 相似文献
19.
Processing of lipoxygenase-free soybeans and evaluation in foods 总被引:2,自引:2,他引:0
J. M. King S. M. Chin L. K. Svendsen C. A. Reitmeier L. A. Johnson W. R. Fehr 《Journal of the American Oil Chemists' Society》2001,78(4):353-360
Lipoxygenase-free soybeans were processed into flour, concentrate, and isolate and compared to normal soybeans in bread, meat
patties, and a beverage, respectively. Bread made with 20% normal or lipoxygenase-free soy flour had greater (P< 0.05) beany flavor than control yeast bread. There were no differences in beany flavor scores between soy flour types, normal
and lipoxygenase-free. Ground beef patties made with 5% acid-washed or ethanol-washed soy protein concentrate had greater
(P<0.05) beany flavor than control ground beef patties. Ground beef patties made with ethanol-washed concentrate were scored
lower in beany flavor than those made with acid-washed concentrate from normal soybeans. There were no differences in beany
flavor between normal and lipoxygenase-free soy isolate in 2%-fat or no-fat beverages. Comminuted meat products made with
lipoxygenase-free soy proteins, especially ethanol-washed concentrate, have potential for making soy foods with less beany
flavor than foods made with normal soy. 相似文献
20.
The effects of hydrothermal cooking on the functional properties of defatted soy flour, aqueous alcohol washed soy protein
concentrate, and soy protein isolate were determined in samples that were treated at 154°C by infusing steam under pressure
for 11, 19, 30, and 42 s, and then spray dried. Hydrothermal cooking increased the nitrogen solubility index (NSI) of the
concentrate from 15 to 56% and altered the solubility profile from a flat profile to one more typical of native soy protein.
Hydrothermal cooking also improved foaming and emulsifying properties of the concentrate. For isolate, hydrothermal cooking
also improved NSI and foaming and emulsifying properties, although the improvements were less dramatic than with concentrate.
NSI and emulsifying properties of the flour were improved by some processing conditions, but foaming properties were not improved
by hydrothermal cooking. Dramatically increased protein solubility of concentrate and modestly improved protein solubilities
of flour and isolate by hydrothermal cooking, which will also inactivate trypsin inhibitors and microorganisms, have considerable
practical significance to protein ingredient manufacturers and those who use these ingredients in foods and industrial products. 相似文献