| 摘要 |
A method of preparing OSB (oriented strand board) binders consisting of modified tannins in solid particulate form and dry blended in a specific manner with spray dried phenolic resole adhesives, the hybrid polymer mix made without the inclusion of any additional formaldehyde 'donors' normally used with the tannin binder s. The novel dry mix of specific ratios of dry tannin/phenolic powders when applied to OSB wood wafers and strands in the OSB mill blender allows the mill to implement a reliable new OSB binder adhesive system comprising of various in-situ reactions of the synthetic/natural polymer components in the OSB mill press and finished board. The produced OSB boards exhibit mechanical strength and water resistance properties equal to or superior to OSB boards made with the spray dried phenolic adhesives normally used as the sole OSB binder. The formaldehyde emissions from board pressing operations and from the final finished OSB board are reduced because the tannin acts as a formaldehyde "scavenger" in-situ. The OSB produced with the novel binder mix shows improved mould growth resistance.
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