Li-ying Guo, Bin Zhang, Zhi-ming Wang, Xiu-yun Ma, Peng-cheng Huang. Preparation of Phenolic Resin Composites with Functional Ionic Liquids and Their Liquefaction Product of Wood Powder[J]. Acta Polymerica Sinica, 2015,(5):556-563.
Functional ionic liquids of 1-(2-hydroxyethyl)-3-methyl imidazole chloride ([HeMIM]Cl)
1-ethylamine-3-methyl imidazole bromide ([AeMIM]Br) and 1-carboxy ethyl-3-methyl imidazole chloride ([CeMIM]Cl) were synthesized and characterized by FTIR and 1H-NMR.After dissolving in the ionic liquids for 3 h
the liquefied wood powder obtained was blended with phenol and formaldehyde in situ to prepare phenolic resin composites.The effects of the ionic liquid types on the dissolution rate of wood powder and the properties of phenolic resin were studiced through the tests of chemical structure
mechanical properties and morphology by FTIR
XRD
DSC and SEM.The results showed that the mechanical properties of the phenolic resin composites were improved obviously by ionic liquid and its solubility product of wood powder.The wood powder showed the highest liquefaction rate in [CeMIM]Cl
reaching 24.6% at 90 ℃.When the weight ratio of [CeMIM]Cl to wood powder was 10:1
the free formaldehyde content in the phenolic resin composites was decreased from 3.64% to 0.92%.The impact strength of phenolic resin modified with [AeMIM]Br was increased from 0.93 kJ/m2 to 6.96 kJ/m2
while the tensile strength of phenolic resin modified with [AeMIM]Br and its liquefaction of wood powder was increased from 3.28 MPa to 9.70 MPa.