สำนักราชบัณฑิตยสภา

วารสารราชบัณฑิตยสถาน ปีที่ ๓๗ ฉบับที่ ๑ ม.ค.-มี.ค. ๒๕๕๕ Abstract Using recycled paper is one way to reduce environment problems. However, higher cycle numbers of recycling leads to reduction of paper strength; thus, improvement of recycled paper properties is very important. One way to improve strength of recycled paper is to use kapok pulp because kapok is the long fiber and a large number of kapok fibers are found in Thailand. In this study, paper was made by using kapok and recycled pulp to compare with those using softwood pulp-to-recycled pulp ratios at 100:0, 10:90, 20:80, 30:70 and 0:100. As a result, it was found that recycling up to three cycles had a small effect on paper properties. A higher amount of kapok pulp in the mixed pulp between kapok pulp and recycled pulp increased opacity, density and tensile index but decreased brightness, whiteness and porosity of handsheets. On the other hand, the higher amount of softwood pulp led to higher porosity and tear index. So, the combination and amount of pulps used is really dependent on the final paper property required. Key words: recycled paper, kapok, softwood, paper properties Introduction Waste paper recycling now becomes remarkably important due to environmental concerns, increasing paper consumption, government regulations, deforestation, fiber shortage in some countries and so on. However, the challenging part of waste paper recycling is the quality improvement of paper made from these recycled fibers since the pulp quality especially the paper strength is normally decreased after repeated recycling. Generally, the way to improve recycled pulp strength can be done by refining that pulp before making it into sheets of paper. By doing so, recycled pulp is fibrillated and this can increase the surface areas of fibers available for water absorption and bonding. Another way of improving the strength property of paper made from USE OF KAPOK PULP TO IMPROVE PROPERTIES OF RECYCLED PAPER Somporn Chaiarrekij, Sannipa Pattanapiyasup, Sudtatip Lekhalawan, and Supanee Phiphatwitthay Department of Imaging and Printing Technology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand, Suda Kiatkamjornwong Associate Fellow, Acadeymy of Science, The Royal Institute, Thailand,