الفهرس | Only 14 pages are availabe for public view |
Abstract The studied properties included dimensional stability properties: water absorption (WA2.24), volumetric swelling coefficient (S2,24), antishrink efficiency (ASE2.24) after 2 and 24 hours water soak as well as static bending properties: modulus of rupture (MOR) and modulus of elasticity (MOE), shear stress parallel to grain (Ss) and abrasion resistance (Ar)’ The results of this study showed significant difference between the behavior of the treated specimens compared with the untreated control specimens. The analysis of the results points to an appropriate value of concentration to achieve the maximum retention levels of impregnation media reaching 25% with MF, LS, PFw and Pest>while attaining only 15% with other polymers. Most of the treatments showed recognized influence on dimensional stability. For example, the treatment with MF has resulted into a decrease of volumetric swelling coefficient from 20.2% to 1.5% and from 71.6% to 9.6% after 2 and 24 hours water submersion test respectively.as compared to the control and water absorption decrease by weight from 37.2% to 4.9% and from 165.1% to 32.6% after 2 and 24 hours water submersion test respectively as compared to the control. The impregnation by PS, Pest. LS, and PFa increased the MOR values by up to 35% for both Pest and PS, 30% and 23% for aIcoholsoluble phenol formaldehyde’ and linseed oil respectively. The MOE values increased by up to 45% for PS, 35% for polyester and 33% for alcohol-soluble phenol formaldehyde. The treatment with LS, MMA, Pc~t and MF inc.eased the abrasion resistance by up to 61 (Yu Ior methyl mcthucrylutc, 43% for linseed oil, ~]% lor polyester and 17% 1’01 melamine formaldehyde, while 110 treatment improved the shear strength of the DPLM. Thus, select ive treatments could be chosen, for the improvement physical and mechanical properties 01 0PLM, .iased on the needed application and end use. |