Graft Copolymers of Lignin with 1-Ethenylbenzene. 2. Properties
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- 作者：Meng-Jiu Chen ; D. W. Gunnells ; Douglas J. Gardner ; Oleg Milstein ; Rolf Gersonde ; H. J. Feine ; Aloys Hü ; ttermann ; R. Frund ; H. D. Lü ; demann ; and John J. Meister
- 刊名：Macromolecules
- 出版年：1996
- 出版时间：February 26, 1996
- 年：1996
- 卷：29
- 期：5
- 页码：1389 - 1398
- 全文大小：320K
- 年卷期：v.29,no.5(February 26, 1996)
- ISSN：1520-5835
文摘
The graft copolymerization of lignin and 1-ethenylbenzene wascoinitiated by lignin, calciumchloride, and hydrogen peroxide in dimethyl sulfoxide solution.Conversion of 1-ethenylbenzene and yieldof polymerized product of 90% or more were obtained. Thecopolymerization reaction changes thehydrodynamic radius of the product. Grafting has changed thesurface properties of the original ligninfrom hydrophilic to hydrophobic. The copolymerization product is athermoplastic material. White rotBasidiomycete were able to biodegrade styrene(1-ethenylbenzene) graft copolymers of lignin containingdifferent proportions of lignin and poly(1-phenylethylene).The polymer samples were incubated withwhite rot Pleurotus ostreatus, Phanerochaetechrysosporium, and Trametes versicolor and brownrotGleophyllum trabeum. White rot fungi degraded theplastic samples at a rate which increased withincreasing lignin content in the copolymer sample. Bothpoly(1-phenylethylene) and lignin componentsof the copolymer were readily degraded.Poly(1-phenylethylene) pellets were not degradable inthesetests. Observation by scanning electron microscopy of incubatedcopolymers showed a deterioration ofthe plastic surface. Brown rot fungus did not affect any of theseplastics. The FTIR of the graft copolymersshows a series of characteristic absorbance peaks from multisubstitutedaromatic rings and a strongpoly(1-phenylethylene) (polystyrene) absorbance peak frommonosubstituted aromatic rings. Subtractionof copolymer spectra taken after 50 days of incubation with the fourtested fungi from spectra takenbefore incubation shows the loss of functional groups from thecopolymer. The graft copolymer with longpoly(1-phenylethylene) side chains is a macromolecular surfaceactive material because in each graftmolecule, a long hydrocarbon side chain has been grown off of a natural(oxyphenyl)propyl backbone.Surface activity of the graft copolymers is indicated by theircapacity to form stable emulsions betweenincompatible fluid phases and to adhesively bond to wood surfaces.Dynamic contact angle measurementusing the Wilhelmy plate technique shows that the graft copolymerschange the contact angle of wateron wood from 50 to 110
. The copolymerization product and itsfractions have a coupling effect in theconnection of wood to poly(1-phenylethylene). Lap shearstrengths increase 56%, from 1826 to 2840 kPa,when the wood is coated with a graft copolymer containing 51.7%lignin.
. The copolymerization product and itsfractions have a coupling effect in theconnection of wood to poly(1-phenylethylene). Lap shearstrengths increase 56%, from 1826 to 2840 kPa,when the wood is coated with a graft copolymer containing 51.7%lignin.