Alternatiivid fenoolformaldehüüdvaigule kasevineeri tootmisel
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Kuupäev
2023
Kättesaadavus
09.09.2023
Autorid
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Eesti Maaülikool
Abstrakt
Käesolevas magistritöös võrreldakse paindetugevuse, paindeelastsusmooduli ja liimühendus
kvaliteedi näitajaid vähendatud vaba formaldehüüdi sisaldusega (UF, MUF, LPF) või
formaldehüüdivabade (PVAc, EPI) liimainete kasutamisel fenoolformaldehüüdvaigu (PF)
alternatiivina kasevineeri tootmisel. Põhieesmärgina leitakse sobivamad alternatiivid
fenoolformaldehüüdvaigule lähtudes katsete tulemustest. Töös kasutatakse kuute erinevat liimi
tüüpi (EPI, LPF, MUF, PF, PVAc XT5/XT7, UF). Metoodika seisneb spooni mõõtusaagimises,
spoonilehtede liimimises, spoonipakettide pressimises, katsekehade mõõtusaagimises ning katsete
läbiviimises vastavalt Euroopa standarditele. Vineer toodetakse Eesti Maaülikooli puidutöökojas.
Liimühenduse kvaliteedi katsetulemused kinnitavad kõikide liimi tüüpide vastavust standardi
EVS-EN 314-2:1999 sätestatud klass 1 (kuivad kasutustingimused) nõuetele, ületades
nihketugevus väärtuse 1 N/mm² kõikides spoonikihtides. Standardis EVS-EN 314-2:1999
sätestatud klass 3 (välitingimused) nõuetele ei vastanud ainsana PVAc XT5 kolmanda spoonikihi
nihketugevus väärtus (0,99 N/mm²). Fenoolformaldehüüdvaik omas keskmiselt 13 – 31%
suuremaid paindetugevus ja paindeelastsusmooduli väärtusi võrreldes formaldehüüdivabade
sideainetega ning 2 – 18% suuremaid tugevusomadusi võrreldes vähendatud vaba formaldehüüdi
sisalduse liimainetega. Lähtudes katsetulemustest oleks parimateks võimalikeks
fenoolformaldehüüdvaigu alternatiivideks kasevineeri tootmisel LPF ja EPI sideained kuna
nihketugevuse ja tugevusomaduste mõõtmisandmed näitasid võrdväärseid tulemusi PF-vaigule.
In this Master’s thesis, bending strength, the modulus of elasticity and the bonding quality are compared in case of using reduced free formaldehyde content (UF, MUF, LPF) or formaldehydefree (PVAc, EPI) adhesives as an alternative for phenol formaldehyde (PF) resin in the production of birch plywood. The main objective is to find suitable alternatives to phenol formaldehyde on results of the tests. The work uses six different types of glues (EPI, LPF, MUF, PF, PVAc XT5/XT7, UF). The methodology consist of sawing veneer, gluing veneer sheets, pressing veneer packages, sawing test pieces and conducting tests according to the European Standards. Plywood is produced at the wood workshop of the Estonian University of Life Sciences. The results of the bonding quality confirm that all types of adhesives fulfill the requirements of class 1 (dry interior) of standard EVS-EN 314-2:1993 by exceeding the shear strength of 1 N/mm² in all veneer layers. The shear strength value (0,99 N/mm²) of the third veneer layer of PVAc XT5 was the only one that did not fulfill the requirements of class 3 (non-covered exterior) enacted in standard EVS-EN 314-2:1993. Phenol formaldehyde resin had on average 13 – 31% higher bending strength and modulus of elasticity values compared to formaldehyde-free adhesives and 2 – 18% higher strength properties compared to reduced free formaldehyde content glues. Based on the test results, the best possible alternatives to phenolformaldehyde resin in the birch plywood production would be LPF and EPI adhesives as test results for shear strength and strength properties showed equivalent results for PF resin.
In this Master’s thesis, bending strength, the modulus of elasticity and the bonding quality are compared in case of using reduced free formaldehyde content (UF, MUF, LPF) or formaldehydefree (PVAc, EPI) adhesives as an alternative for phenol formaldehyde (PF) resin in the production of birch plywood. The main objective is to find suitable alternatives to phenol formaldehyde on results of the tests. The work uses six different types of glues (EPI, LPF, MUF, PF, PVAc XT5/XT7, UF). The methodology consist of sawing veneer, gluing veneer sheets, pressing veneer packages, sawing test pieces and conducting tests according to the European Standards. Plywood is produced at the wood workshop of the Estonian University of Life Sciences. The results of the bonding quality confirm that all types of adhesives fulfill the requirements of class 1 (dry interior) of standard EVS-EN 314-2:1993 by exceeding the shear strength of 1 N/mm² in all veneer layers. The shear strength value (0,99 N/mm²) of the third veneer layer of PVAc XT5 was the only one that did not fulfill the requirements of class 3 (non-covered exterior) enacted in standard EVS-EN 314-2:1993. Phenol formaldehyde resin had on average 13 – 31% higher bending strength and modulus of elasticity values compared to formaldehyde-free adhesives and 2 – 18% higher strength properties compared to reduced free formaldehyde content glues. Based on the test results, the best possible alternatives to phenolformaldehyde resin in the birch plywood production would be LPF and EPI adhesives as test results for shear strength and strength properties showed equivalent results for PF resin.
Kirjeldus
Magistritöö
Metsatööstuse õppekaval
Märksõnad
magistritööd, vineer, ligniin, formaldehüüdivaba liim