Recently, lignophenols have been obtained from lignin in wood-sources, and now, the establishment of their industrial materials is required.We tried to apply them to adhesives for wood, because they have phenolic and alcoholic hydroxy groups, and it seems that the hydrogen bond can be formed between electron-withdrawing substituent.We used them as adhesives materials by conjugated with polymer having electron-withdrawing substituent.As a result, the composite of lignophenol and sodium polyhydroxyacrylate has enough adhesive strength for wood.In addition, relation of hydrogen bond property and adhesive strength were considered from IR and DSC analysis of the composites.

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Toexplorethepossibilityofutilizingsilkfibroin(SF)asawoodadhesiveandtoimprovethewaterdurabilityoftheSFbytheadditionofanaqueousemulsion-typeisocyanateresin(EIC),acompressivesheartestandcharacterizationofthefilmpreparedfromEICandSFwereconductedThebondstrengthofSFdidnotdecreaseinspiteofimmersionin30℃waterfor3hours.ThebondstrengthwasmodifiedwithanincreaseintheEIC/SFratios,althoughwoodfailureofallspecimenswerelessthan10%withimmersionofthespecimensin60℃hotwaterfor3hoursTheresultsoftensiletestofEIC/SFfilmssuggestedthatthelowerwoodfailurewascausedbyadecreaseinthecohesionforceoftheadhesivelayerbysorptionofwater.TheglasstransitiontemperatureofEIC/SFfilmsshiftedtoalowertemperatureandthethermalexpansioncoefficientincreasedastheEIC/SFratioincreased.Consequently,thecrystalformationofsilkfibroinincludingsilkIIformationservesasthehardsegmentoftheEIC/SFfilmsandEICthatreactedwithwaterorpolyolsincludedindenaturedEICservesasthesoftsegment

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