预埋PVC管空心刨花板平压成型技术

Fabrication of hollow particleboards using flat-pressing with pre-buried PVC tubes

针对现有空心刨花板纵向强度低,对刨花要求高和需脱膜等缺陷,以不同板材厚度、空心孔距和芯层比例(芯层刨花质量比)作为影响因素,采用预埋PVC管平压成型的方式制造空心刨花板,对板材主要物理力学性能进行测试和分析。研究表明:采用预埋PVC管进行平压式空心刨花板制造是可行的,对板材性能有较大的增强作用。相同密度下厚度为16 mm的板材力学性能最好,芯层所占比例为2/3时,PVC管孔截面变形最小,空心孔距对板材力学性能影响不显著。板材的24 h吸水膨胀率(TS)随着厚度的增大呈下降趋势,力学性能随着厚度的增大而先下降后上升。当厚度为16 mm时,板材静曲强度(MOR)达到12.66 MPa,弹性模量(MOE)达到1.444 GPa,而24 h TS达到11.80%。板材的MOR和MOE随空心孔距的增大呈先下降后上升的变化趋势,对24h TS无明显影响,当空心孔距为20 mm时,板材的MOR达到12.47 MPa、MOE达到1.336 GPa、而24 h TS达到11.62%。板材的MOR和MOE随芯层比例的增大呈先下降后上升的变化趋势,对24 h TS无明显影响,当芯层比例为2/3时,板材的MOR达到12.04 MPa,MOE达到1.302 GPa,而24 h TS达到了10.68%。

Due to the drawbacks of current hollow parficleboards such as low longitudinal strength, large consumption of wood shavings and requirement of de,holding, we fabracated hollow particleboards with different thickness, hollow hole distances and core layer rates using fiat-pressing that were pre-buried by PVC tubes as hollow channels in boards. The main physical and mechanical properties were examined. The results showed that the technology of the flat-pressing with pre-buried PVC tubes was feasible to make hollow particleboards, which can greatly improve the mechanical properties. Under the same density, when the thickness was 16 ram, the best mechanical properties of particleboard were achieved. When the core layer rate was 2/3, the PVC tube＇s diameter was smallest, the hollow hole distance had no remarkable influence on the mechanical properties of the panels. The 24 h water absorption thickness swelling （TS） declined with the increase of thickness, while its mechanical performance declined firstly and then increased. When the thickness was 16 mm, MOR was 12. 66 MPa, MOE was 1. 444 GPa, and 24 h TS was up to 11.80%. MOR and MOE decreased firstly and then increased when the hollow hole distance become larger, but it had no obvious influence on the 24 h TS. When the hollow hole distance was 20 ram, MOR was 12.47 MPa, MOE was 1. 336 GPa, and the 24 h TS was up to 11.62%. MOR and MOE decreased firstly and then increased as the core layer rate changed, while it had no obvious influence on the 24 h TS as well. When the core layer rate was 2/3, MOR was 12. 04 MPa, MOE was 1. 302 GPa, and 24 h TS was 10. 68%.