• Journal of the Korean Wood Science and Technology
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• 제32권3호
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• pp.42-51
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• 2004

Wood veneer-bamboo zephyr composite board (WBCB) was manufactured to evaluate the properties of bamboo as alternative raw materials for the manufacture of composite panels. Bamboo zephyr was prepared using Moso bamboo (Phyllostachys pubesens Mazel. et Z), Giant timber bamboo (Phyllostachys bambusoides Sieb. et Zucc), and Hachiku bamboo (Phyllostachys nigra var. henosos Stapf). The effect of age and species of bamboo on zephyr production was investigated in terms of the pass number of bamboo split through the rollers, and the width increasing rate of bamboo split. Five-ply WBCBs were produced with Keruing veneers as face and back layers, leading to three layers of bamboo zephyr sheets as core layer. Each layer was placed so that its grain direction was at right angles to that of the adjacent layer and the layers were bonded together with phenol-formaldehyde (PF) resin.The pass number of bamboo split was increased with an increase of the thickness of culm wall. At the same thickness, Moso bamboo showed no effect of the age of bamboo on the pass number. The pass number of split of Giant timber bamboo was lower than that of Moso bamboo. No significant effect of bamboo species and age on the width of zephyr produced was observed. The width of zephyr obtained could be expressed as a function of diameter multiplied by thickness of culm wall. The physical and mechanical properties of WBCB manufactured in all given conditions did not show any significant differences, and they were above the requirement of Korean Standard (KS).

• Journal of the Korean Wood Science and Technology
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• 제35권6호
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• pp.108-117
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• 2007

생장 기간이 매우 빠르고 섬유방향의 강도적 성질이 우수한 대나무를 합판의 원료로 이용하기 위하여 케루잉단판-솜대 zephyr 복합 패널(WBCB)의 제조 조건(수지접착제의 종류, 도포량, 도포방법)이 패널의 성능에 미치는 영향을 검토하였다. 수지의 종류에 따른 5-ply WBCB의 성능은 폴리메릭 이소시아네이트수지(PMDI)가 가장 좋은 결과를 나타내었으며, 이어 페놀수지(PF), 페놀 멜라민수지, 요소 멜라민수지 및 요소수지의 순이었다. 사용한 수지 중 강도적 측면과 작업성을 고려할 때 PF 수지에 의한 복합 패널 제조가 가장 적절한 것으로 생각된다. PF수지를 사용하여 제조한 12 mm 두께의 5-ply WBCB의 경우, 수지의 도포량이 증가하면 패널의 성능도 향상되는 경향이었다. 또한 박리강도 측정 후의 파괴양상은 도포량이 증가함에 따라 대나무 외층-대나무 내층 경계층의 파괴가 증가한 데 반하여 대나무 제퍼 내부층의 파괴는 상대적으로 감소하였다. 따라서 WBCB 제조시 수지가 다소 zephyr 내부까지 침투할 정도의 수지 도포량이 적절한 것으로 생각되며, 표면 단판의 오염성과 경제성 등을 고려할 때 $320g/m^2$이 가장 적합한 것으로 판단된다. 동일한 PF수지 도포량에서 수지의 도포방법을 달리하여 제조한 5-ply 복합 패널의 성능은 양면과 편면 스프레이 도포 간과 스프레이와 롤러에 의한 도포방법 간에 현저한 차이가 나타나지 않아 주어진 환경에서 작업성이 좋은 도포방법을 채택하면 될 것으로 생각된다.

• Journal of the Korean Wood Science and Technology
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• 제50권2호
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• pp.134-147
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• 2022

The objective of this study is to determine the effect of fiber direction arrangement and layer composition of hybrid bamboo laminate boards on the physical and mechanical properties. The raw material used was tali bamboo (Gigantochloa apus (J.A. & J.H. Schultes) Kurs) rope in the form of flat sheets (zephyr) and falcata veneer (Paraserianthes falcataria (L) Nielsen). Zephyr bamboo was arranged in three layers using water-based isocyanate polymer (WBPI) with a glue spread rate of 300 g/m². There were variations in the substitution of the core layer with falcata veneers (hybrid) as much as two layers and using a glue spread rate of 170 g/m². The laminated bamboo board was cold-pressed at a pressure of 22.2 kgf/cm² for 1 h, and the physical and mechanical properties were evaluated. The results showed that the arrangement of the fiber direction significantly affected the dimensional stability, modulus of rupture, modulus of elasticity, shear strength, and screw withdrawal strength. However, the composition of the layers had no significant effect on the physical and mechanical properties. The bonding quality of bamboo laminate boards with WBPI was considered to be quite good, as shown by the absence of delamination in all test samples. The bamboo hybrid laminate board can be an alternative based on the physical and mechanical properties that can meet laminated board standards.