期刊缩写 WOOD FIBER SCI
期刊全称 WOOD AND FIBER SCIENCE 《木材与纤维科学》
出版国家 UNITED STATES
出版周期 Quarterly
出版商 Society of Wood Science and Te
期刊ISSN 0735-6161
2012-2013最新影响因子 0.717
Wood and Fiber Science is the official publication of the Society of Wood Science and Technology, and accordingly publishes papers with both professional and technical content. Original papers of professional concern, or based on research dealing with the science, processing, and manufacture of wood and composite products of wood or wood fiber origin will be considered.
The Editor
Geza Ifju,
Department of Wood Science and Forest Products,
Brooks Forest Products Center, Virginia Tech
13C CP/MAS NMR as a Direct Probe of the Wood-Phenol Formaldehyde Adhesive Bondline
Authors
Robert G. Schmidt, Graduate Research Assistant1, Charles E. Frazier, Assistant Professor1
1Department of Wood Science and Forest Products Center for Adhesive and Sealant Science Polymer Materials and Interfaces Laboratory, Virginia Polytechnic and State University, Blacksburg, VA XXXX
Abstract
Resole phenol formaldehyde resin was synthesized using 13C labeled paraformaldehyde. Wood flake model composites were prepared with the labeled resin, cured for various times and temperatures, and then characterized by 13C CP/MAS NMR. The relative degrees of adhesive cure were determined from the corrected peak areas of the methylene and hydroxymethyl carbon signals. Similar cure information was provided by measuring rotating frame proton spin-lattice relaxation times. However, cure measurements via relaxation times were less sensitive because of the effects of spin diffusion within the cured resin. Relaxation measurements revealed that wood induces heterogeneity in cured PF, whereas neat-cured PF is normally more homogeneous. This method provides cure and morphological information for intact bondlines. The procedure is readily applicable to pilot or industrial scale manufacturing processes, allowing the direct evaluation of resin cure within a wood-based composite. |
