Insoluble resins containing phosphonium groups were prepared by chlorometbylation andfollowing reaction of used trays or cups of foam polystyrene with trialky lphosphines.Triethylphosphine(TEP),tributylphosphine(TBP)and trioctylphosphine(TOP) were used as trialkylphosphines.The resins obtained by the reactions with TEP,TBP or TOP were represented asPCS-TEP,PCS-TBP and PCS-TOP,respectively.The adsorption ability of the resins for fooddyes(Red-102andYellow-4),sodium benzenesulfonate(SBS),and sodium dodecybenzenesufonate(SDBS)were investigated by a batch method.PCS-TEP and PCS-TBP could highly adsorb Red-102 and Yellow-4 from NaCl solution of its high concentration.The adsorption of SBS decreasedwith increasing ionic strength of the solution,while the adsorption of SDBS and food dyes wasindependent on the ionic strength of the solution.In addition,all resins could remove selectivelySDBS from solutions containing glucose or starch.

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The mechanism of initial formaldehyde emission from plywood prepared with uroa-formaldehyde resin adhesive synthesized under various conditions was investigated by chemical analysisof resin adhesive and by the dependence of formaldehyde emission on temperature.Within 500 hours after plywood preparation , the amount of formaldehyde emission decreased greatly over time. Therefore , the coefficients of formaldehyde emission rate (a) were calculated from the relation between time and the amounts of formaldehyde emission , and there was a conelation between a and the free formaldehyde in resin. Moreover, the relative intensity ratios of some chemical functional groups and bonds, such as the methylol group and dimethylene ether bond in resin, measured by means of ¹³C-NMR,　were　linearly　correlated　with　a.　From　the　dependence　of　formaldehyde　emission　on　temperature,　constant　rates　(k)　wereobtained　when　it　was　assumed　that　formaldehyde　emissio　nunder　various　temperatures　was　a　first-der　reaction.　The　value　of　the　apparent　active　energy　of　formaldehyde　emission　fromplywood,　which　was　obtained　from　the　relation　between　k　and　heating　temperature,　was　smaller　than　that　of　the　decomposition　of　methylene　diurea.　Thus,　within　500　hours　after　plywood　preparation,　it　was　clarified　that　the　free　formaldehyde　in　resin,　and　some　chemical　functional　groups　and　bonds　that　could　form　formaldehyde　in　the　curing　reaction,　principally　influence　formaldehyde　emission　from　plywood.　(Received:February18,2000)

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Variouskindsofpolyhydroxyurethanesweresynthesizedbypolyadditionofbis(cycliccarbonate)sanddiaminetostudythefilmproperties.Thetensilestrengthandelongationpercentageofthepolyhydroxyurethanefilmswerevariedwithdryingconditionsprobablyduetoabsorbedwaterservingasaplasticizer.Thewaterabsorptionpercentagesandthermaldecompositiontemperaturesofthepolyhydroxyurethanefilmswere>30%and32～88℃higherthanthoseofcommercialpolyurethanes,respectively.

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Wood dowel (Acer mono) was joined into wood member (Cryptomeria japonica) by a polymeric MDI(PMDI) or a polyurethane resin , which is an isocyanate adhesive. Infrared microspectrosopicspectra at the joints were 2-dimensionally measured by diffuse reflectance method , and then NCO group was identified due to its asymmetric stretching vibrational band (2270cm⁻¹).Thedistributions　of　the　adhesives　(isocyanate　compounds)　around　the　joints　were　displayed　by　colorscorresponding　to　the　band　intensityat　2270cm⁻¹.　The color maps exhibited that the PADI excessively penetrates into the wood member in the axial direction because of its low viscosity (ca.0.2 Pa．s) , and indicated that only the fluid components in the polyurethane resin (ca.200 Pa・s)　,　which　are　not　so　large　,　move　from　the　glue　line　to　the　wood member. (Received:December15,1999)

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