Synthesis of bio-oilphenol-formaldehyde resins under alkali conditions : physical, chemical and thermal properties of resins and bonding performance = Sinteza bioulja s fenolformaldehidnim smolama u alkalnim uvjetima : fizička, kemijska i toplinska svojstva smola i svojstvo lijepljenog spoja / Günay Özbay, Caglar Cekic, Muhammad Syarhabil Ahmad, Erkan Sami Kokten.
Sažetak

In the present study, bio-oil produced from vacuum pyrolysis of woody biomass has been investigated as a source of chemical feedstock. Bio-based resins were produced using the bio- oil with phenol substitutions ranging from 10 to 30 wt%. The conventional GC/MS analysis was carried out for the evaluation of the chemical composition of bio-oil. TGA, DSC and FT-IR analyses were used in order to characterize the bio-oil-phenol-formaldehyde (BPF) resins. The bonding quality of wood samples bonded with the BPF resins was investigated under different pre-treatment conditions. The highest shear strength was observed for the control samples bonded with the laboratory PF resin. As the amount of bio-oil was increased up to 30 wt%, the shear strength of the samples decreased from 12.08 to 11.76 N/mm2. The bonding performance was not negatively affected by the combination of bio-oil under dry conditions. According to TS EN 12765 standard, the relevant performance requirements for bonded samples under dry conditions must be at least 10 N/mm2. Relating to the standard, all samples bonded with BPF resins obtained the requirements for durability class C1. Under wet conditions, the bonding performance was negatively affected by the addition of bio-oil. However, the BPF resins fulfilled the durability requirements for C1, C2, and C3 specified in EN 12765 (2002).; U radu je predstavljeno istraživanje mogućnosti upotrebe bioulja dobivenoga vakuumskom pirolizom drvne biomase kao izvora kemijske sirovine. Biosmole su dobivene zamjenom 10 – 30 % mase (ili težinskog udjela) fenola biouljima. Analiza kemijskog sastava bioulja provedena je GC/MS metodom. Za karakterizaciju biouljnih fenolformaldehidnih smola (BPF) primijenjene su TGA, DSC i FT-IR analiza. Kvaliteta spoja uzoraka drva slijepljenih BPF smolama ispitivana je pri različitim uvjetima predobrade. Najveća čvrstoća na smicanje postignuta je na kontrolnim uzorcima lijepljenim laboratorijskim PF smolama. S povećanjem udjela bioulja do 30 % mase (ili težinskog udjela), čvrstoća na smicanje smanjila se s 12,08 na 11,76 N/mm2. Prema normi TS EN 12765, čvrstoća na smicanje u suhim uvjetima treba biti najmanje 10 N/mm2. Kombinacija bioulja s fenolformaldehidnim smolama nije negativno utjecala na svojstva slijepljenog spoja u suhim uvjetima i svi uzorci lijepljeni BPF smolama zadovoljili su zahtjeve klase trajnosti C1. U vlažnim uvjetima dodatak bioulja negativno je utjecao na svojstva slijepljenog spoja. Međutim, BPF smole ispunile su zahtjeve trajnosti za klase C1, C2 i C3 propisane normom EN 12765 (2002).