Alignment of Bacterial Cellulosic Materials
Improved material properties can result when polymers are aligned. The objective of this study is to examine the potential for electrofluidic alignment in cellulose-based materials. This project is being conducted by Michelle Cruz, who is part of NSF’s REU program.

Radio Frequency (RF) Cycle Times and Polyvinyl Acetate Adhesive Performance
A company in southern Pennsylvania is interested in determining optimum RF cycle times can be determined for edge glued panels. In this project, panels consolidated under different RF cycle times are being evaluated via simple compression shear block testing, as well as through dynamic mechanical analyses (DMA). Four different cycle times are being considered. Different humidity conditions are also being applied to determine the effects of accelerated aging on the adhesives. Thanks to Austin Graybill and Kristina Baldwin for their work on this project.

Effect of 2,4 - MDI Isomer Ratio Content on PMDI-Wood Adhesion and Composite Performance
Tom Ruffing just began a project on this subject, in conjunction with BayerMaterials Science. Look for more details here as Tom's work advances.

Isocyanate Resin and Species Dependent Performance
Mike Gruver’s research project was to evaluate the penetration and performance of pMDI resin on selected wood species. Previous research by Frazier and Malmberg demonstrated that isocyanate resin behaves differently on different wood species. Here, we are explored the mechanisms for this occurrence. In particular, anatomical effects of wood species were considered. The wood species used included aspen (Populus grandidenta), yellow-poplar (Liriodendron tulipifera), and southern yellow pine (Pinus spp.). Compression shear block tests, fluorescence microscopy, and DMA were used to probe isocyanate-wood penetration and adhesion. Waferboard composites were also made and tested through interactions with a PA company. Look for publications to be submitted from this work within 2006.

Co-monomer Distribution in Polyvinyl Acetate Latex Adhesives
Many secondary manufacturing operations use cross-linking polyvinyl acetate adhesives to join small clear sections of wood, yet relatively little information is available about these systems. These adhesives are typically made by copolymerizing vinyl acetate with a small amount (less than 5% w/w on vinyl acetate) of a multifunctional co-monomer. Cross-linking reactions of the co-monomer are thought to provide greater durability to the adhesive. This project had two main objectives: 1. to determine the distribution of NMA (N-methylolacrylamide, which is the multifunctional co-monomer employed here) in the latex; and 2. to determine if NMA distribution in the latex correlates with the durability of the adhesive. Publications are currently being submitted on this work.