Adhesive properties of soy protein as a wood adhesive /
Research was conducted to obtain information that can be used to prepare wood adhesives from soy protein. Wood adhesives were prepared from defatted soy flour and whole extracted soy protein, 7S protein fraction and 1 1 S protein fraction using a slightly modified Lainbuths method. Adhesive strengt...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1997.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739888081&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Research was conducted to obtain information that can be used to prepare wood adhesives from soy protein. Wood adhesives were prepared from defatted soy flour and whole extracted soy protein, 7S protein fraction and 1 1 S protein fraction using a slightly modified Lainbuths method. Adhesive strength (the break load in kg required to break the glued joints) of the formulated soy protein adhesive was measured by a tensile test using an Instron Universal Testing Machine. The wood pieces (2 x 6 x 0.3 cm) used in the test were hard maple wood. The adhesive strength of the whole extracted soy protein glue increased sharply until its concentration reached 12%. A minimum of 25 mg/cm2 adhesive was needed for proper bonding and reproducible results. The viscosity of the defatted soy flour adhesive dropped rapidly from 4,400 mPa to 1,000 mPa within 2 hr of formulation and leveled off at 500 mPa. The cell wall components, not protein, and their hydrolysis products were responsible for viscosity because the initial viscosity of the whole extracted soy protein adhesive was very low at 130 mPa. Both mechanical bonding and molecular bondings were involved in the adhesion of wood with defatted soy flour glue. The whole extracted soy protein adhesive exhibited a break load of 73 kg under the pressing conditions of 3 kg/cm2, 120[]C, and 5 min. Protein was the main component responsible for the adhesion phenomena, while cell wall materials, one of the main constituents of defatted soy flour, had little or no influence on adhesion. The 7S protein adhesive showed a better break load (75 kg) than either the defatted soy flour adhesive (73 kg) or 1 1 S protein adhesive (72 kg). The hydrophobic bond disturbing agent, sodium dodecyl sulfatea (SDS), had no effect on the break load, while hydrogen and covalent bond interfering agents, i.e., urea and []- mercaptoethanol, respectively, caused a decrease in break load of the adhesives. The bond strength of the 1 1 S protein adhesive was adversely affected by []- mercaptoethanol. The adhesive strength of 1% alcalase- modified whole extracted soy protein (AMWESP) decreased sharply from 78 kg to 10 kg in 2 min of hydrolysis and then leveled off. The sodium dodecyl sulfate-polyacrylamide gel electrophoretic pattern of AMWESP at 2 min was almost identical to that at 20 min. |
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| Item Description: | Vita. "Major Subject: Food Science and Technology". |
| Physical Description: | xii, 102 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 89-100. |