低甲醛耐燃再生粒片板之性質

Abstract

本研究目的在使用廢棄木粒片噴塗不同粒片重量比例之異氫酸鹽膠( PMDI )和酚甲醛膠( PF )，以製造適合室內環境使用的低甲醛粒片板。由試驗得知，隨著噴塗PMDI膠粒片重量比例之提升，粒片板甲醛釋出量呈現線性減少，當粒片噴塗PMDI / PF重量比例為70 / 30時，甲醛釋出量為0.29 mg/L，釋出量已達0.3 mg/L以下，施以美拉敏含浸紙貼面後，甲醛釋出量也可降低17 %左右。此外，在力學性質方面，粒片板的抗彎強度、內聚強度和木螺絲保持力均隨著粒片噴塗PMDI膠重量比例之上昇而增加，而吸水厚度膨脹率則隨著粒片噴塗PMDI膠重量比例之上升而下降。美拉敏含浸紙板在改善粒片板的性質上，對粒片板的甲醛釋出量以及抗彎強度等性質較有顯著的改善、但對於內聚強度以及吸水厚度膨脹率的改善則較無效果。 另外，超音波速和粒片板的抗彎強度、內聚強度和木螺絲保持力各項力學性質之間，也有顯著的正相關性，以超音波測定評估素面及化粧粒片板的抗彎強度、內聚強度及木螺絲保持力時，此3項性質均有隨超音波速增加而增大的趨勢。此表示可以藉由粒片板超音波速的測量，來得知粒片板的力學性質。 在粒片板的耐燃性質方面，將甲醛釋出量可通過CNS 2215 F1標準，即噴塗PMDI / PF粒片重比例為100 / 0、70 / 30和50 / 50之三組條件粒片板，經由刷塗耐燃塗料以及噴塗耐燃藥劑於粒片上之兩種耐燃處理方式製成耐燃粒片板，測試後均可通過CNS 6532耐燃三級之標準。經過耐燃藥劑處理之粒片板其抗彎強度、內聚強度及木螺絲保持力等性質都會降低，但吸水厚度膨脹率則會改善。

The objective of this study was to manufacture low formaldehyde emission particleboard made from recycled wood-waste chips by using isocyanate (PMDI) and phenol-formaldehyde (PF) resins for use in indoor environments. The influence of PMDI/PF ratios in particles on the formaldehyde emissions and its mechanical properties were investigated. The experimental results showed that the formaldehyde emissions decreased linearly with an increase of PMDI/PF particles ratio. Their relationship could be represented by the linear regression formula. The value of formaldehyde emissions was below 0.3 mg/L, when the weight percentage of PMDI/particles was up to 70%. The formaldehyde emissions of melamine-formaldehyde (MF) resin-impregnated paper overlaid particleboard was 17% lower than that of particleboard. Moreover, the bending strength, internal bonding strength and screw holding strength increased with an increase of PMDI/PF particles ratio. However, the thickness swelling (%) of the particleboards was decreased with an increase of PMDI/PF particles ratio. In addition, there were significant positive relationships between the ultrasonic velocity and the bending strength, internal bonding strength and screw holding strength of the particleboard, and this meant that we could evaluate the properties of the particleboard using ultrasonic velocity. The fire-resistance properties of the fire-retardant treated particleboard could pass the standard of “Grade 3 Imcombustibility” as specified by CNS 6532. The bending strength, internal bonding strength, and screw holding strength were lower than particleboard but the thickness swelling (%) was improved.