Resin Systems and Glass Reinforcements to Improve Dry-Formed Hardboards.
Abstract
Various resin systems and quantities of resin and a glass yarn scrim were investigated to determine whether they improved stiffness and linear stability of dry-formed, medium-and high-density hardboards. The following resins were used: A low-viscosity (penetrating) and a medium-viscosity (typical bonding type) phenolic, separately, in combination, or viscosity-modified; a two-part epoxy resin; and a powdered thermoplastic resin either separately or in combination with the low-viscosity phenolic. Increasing the quantity of phenolic resin improved both wet-formed and dry-formed board properties but at a diminishing rate with the increase. The low-viscosity phenolic or a combination of the low-and the medium-viscosity phenolic resulted in the best boards. The powdered thermoplastic resin in combination with the low-viscosity phenolic resin provided boards with good wet and dry properties. If analyzed on a total cost basis, this combination of resins has potential as a substitute for phenolic resin. The epoxy system was difficult to handle because of its high viscosity and the tackiness of the fiber after resin was applied. Board strengths were low. The glass yarn scrim pretreated with phenolic resin and bonded to each side of the hardboard mat was highly effective, especially in reducing board linear movement with changes in moisture. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1977
- Accession Number
- ADA042026
Entities
People
- P. E. Steinmetz
Organizations
- Forest Products Laboratory