Development of fire retardant composite panels. Part VIII. Improvement of fire performance of OSB panel via post-treatment with fire retardants, nano-particles, nanocrystalline cellulose and woven glass fiber
To improve fire performance of oriented strand board (OSB), a laboratorial study was carried out to post-treat commercial OSB panel with phenol-formaldehyde (PF) resin containing various fire retardants (FR), nano-particles (NP) and nanocrystalline cellulose (NCC). The post-treatment also included the laminating of OSB panel with woven glass fiber (WGF) and with the same PF resin as a binder. The resultant OSB panels were tested for fire performance in terms of net flame advance, panel consumption, insulation value, and char index.
The test results indicated that the post-treatment improved the fire performance of OSB panel in terms of reduced net flame advance (up to 29%), panel consumption (up to 29%), insulation value (up to 17%), or char index (up to 33%), as compared to the untreated OSB panel. No treatment performed consistently better than others with regard to all fire properties measured, but laminating OSB panel with WGF appeared to be the most effective treatment for protecting OSB against flaming, which resulted in net flame advance decreased by 29%, panel consumption by 29%, and insulation value by 17%. An increase in the loading level of fire retardant from 10 to 15 parts or nano-particle from 5.3 to 13.1 parts per 100 parts of PF did not seem necessary for further improving fire performance for all additives.
Besides WGF, the post-treatments leading to apparently improved fire performance included: (1) fire retardant BUDIT 380 (10 parts/100 parts PF) and nano-particle Cloisite 25A (13.1 parts/100 parts PF) in terms of lowered net flame advance (25% and 24%, respectively); (2) nano-particle Nanofil®SE 3000 (5.3 parts/100 parts PF) in consideration of lowered panel consumption (18%); (3) fire retardant CROS 481A (15 parts/100 parts PF) with respect to lowered insulation value (16%); and (4) fire retardant CROS 349 (10 parts/100 parts PF) (33%), fire retardant CROS 334 (15 parts/100 parts PF) (33%) and nano-particle Nano Al2O3 (13.1 parts/100 parts PF) (31%) with regard to reduced char index. In addition, this study showed that coating OSB with PF alone also seemed to be effective approach for protecting OSB panel against flaming as well, indicated by the lowered net flame advance (20%), panel consumption (13%) and char index (28%).