Global Journal of Science Frontier Research, G: Bio-Tech & Genetics, Volume 22 Issue 2

200°C was high significant different but 220 °C and 240 °C were not significant different. The length of time of PF density was 0.705 ±0.040 g/cm 3 in CL, 0.676 ±0.041 g/cm 3 in4 min, 0.679 ±0.038 g/cm 3 in 8 min, and 0.681 0.±033 g/cm 3 in 12min. One-way ANOVA analysis. the result illustrated that different length of times thermal treatment as the control compared between group (4 min, 8 min and 12 min) were significant different, as P<0.05 (P=0.000, P=0.001 and P=0.002) respectively. To compared 4 min with 8 min and 12 min were no significant and 8 min with 12 min was no significant different. The water absorption (WA)of plywood showed that it was 31.07±4.60, to compared control with different level of temperature at 180 °C for PF was increased 6.05%,thermo-treatment at 200°C was increased 1 %, thermo-treatment at 220°C was increased 4.9 %, and thermo-treatment at 240°C increased 2.55 %, According to Uribe and Ayala (2015) confirm that WA of treatment solid teak has 25 mm thick for 2 hour in different level of temperature, it was 4 % at 180°C, 3.6 % at 200 °C, and 2 % at 210 °C as much different of this study. In contrast, this study was similar with Islam et al. (2012) studied WA in plywood of Eucalyptus camaldulensis , the WA was 36.9±3.82 %. DEL MENEZZI et al. (2017) studied that the WA of teak plywood absorption were improved depend on volume of gluing speed as 0.96 g/m 2 , 1.92 g/m 2 , and 2.88 g/m 2 , the WA were 36.08 %, 30.26 %, and 25.20 %. Thermo- teak plywood in this study used gluing speed was 150 g/m 2 the WA range from 31.07-37.12 % for PF, 31.49- 37.26 %. In conclusion, thermal treatment was not improved WA, but volume of gluing speed was significant for plywood. One-way ANOVA in Duncan analysis the water absorption which it groups a was significant different with b (a=180°C, 220°C and b=control, 200 °C , 240 °C). One-way ANOVA analysis the variable multiple comparison of times length different for teak thermal plywood, The between group to compared control with 4 min was high significant different (P=0.00), to compared control with 8 min was significant different (P=0.02), to compared control with 12 min was no significant different (P=0.45), to compared 4 min with 8 min was high significant different (P=0.00), to compared 4 min with 12 min was high significant different (P=0.00) and to compared 8 min with 12 min was significant different (P=0.01). The swelling thickness of thermo-teak plywood showed that the control was 3.08±1.12 %, the thermo- treatment at 180, 220, 240°C was increased from a control of 1.48,0.46, 0.51 % respectively. But at 200 °C the swelling thickness comparison with control was decreased 1.36 %. Bas on Uribe and Ayala (2015) showed the swelling thickness of teak treatment at 180 °C was0.8 %, at 200 °C was 0.6 %, and 210 °C was 0.5 % which it was decreased in different level of temperature but teak thermo-plywood of this study was not change. The mean value of eucalyptus plywood (1.5%) was evidently lower than that of simul plywood (2.9%) (Islam et al. , 2012). This study was higher Ayala (2015), and Islam et al. (2012) because the high temperature was changed physical property of thin veneer. However, water has been absorbed as well. Base on Duncan in One-way ANOVA analysis grouping significant different, the thickness swelling thermal treatment at 200°C was significant different with control, 220°C and 240°C (P=0.00) and 180°C, but control compared with at 220, and 240°C was no significant different (P=0.41, 0.36) respectively. And to compared 180°C with control sample was significant different (P=0.01), at 200°C was significant (P=0.01) and at 240°C was significant different (P=0.01). The length of time illustrated that the control compared with 4, 8, and 12 min was no significant different (P>0.0.05), to compared 4 min 8 min sample was significant different (P≤0.05), but on 4 min compared with 12 min was no significant different (P>0.05), and 8 min with 12 min was high significant different(P<0.05). Base on this study found that the PF average MOR of control sample was 68.33±20.59 MPa, it was higher than SOUKPHAXAY et al. (2021) studied teak LVL in 6.79 MPa. According to Sutiawan et al. (2021)studied that the influence of different hot pressing condition of Jabon plywood, the MOR perpendicular parallel to grain was increased at high hot pressing i,e., 34.78 MPa at180 °C, 57.51 at 190 °C, and 58.60 MPa at 200°C. This study discussed at 180 °C, and 200 °C was increased in 8.55 MPa of different. But Sutiawan et al. (2021) confirmed that the MOR different between 180 °C to 200 °C was increased 23.82 MPa. The thermo-treatment at different level of temperature was unchanged MOR of the plywood. The MOR of teak LVL used volume of gluing speed in 0.96 g/m 2 , 1.92 g/m 2 , and 2.88 g/m 2 the result was 49.3 MPa, 53.6 MPa, and 74.1 MPa respectively(DEL MENEZZI et al. , 2017). However,The MOR of thermal treatment in different level of temperature were not reduced force loading in the plywood, types and volume spread of adhesives were significant to static bending. MOR in control sample with 180°C was significantly different (P<0.05), to compared control with 200°C, 220°C, and 240°C samples were no significant differences (P>0.05), to compared 180°C samples with 200°C220°C and 240°C samples were significantly different (P<0.05), to compared 200°C with 220°C was no significant different (P>0.05), to compared 200°C with 240°C was significantly different (P<0.05) and to compared 22°C with 240°C was no significant different (P>0.05). MOR of PF group confirm that heat treatment with high temperature was impacted with MOR of teak plywood. The length of time on control compared with 4, 8, and 12 min the result was not significantly different (P>0.05). © 2022 Global Journals 1 Year 2022 80 Global Journal of Science Frontier Research Volume XXII Issue ersion I VII ( G ) Physical and Mechanical Properties of Teak (Tectona Grandis L.Fil.) Thermo-Plywood from Plantations in Lao P.D.R