Influence of Treatment Time and Drying Methods on Impregnating Efficiency of Paraffin Phase Change Material in Rubberwood

 In this work, paraffin C18 phase change material(PCM)withmonoacylglycerolimpregnated into chemically modified rubberwood wasprepared using vacuum impregnationto develop rubberwood/PCMcomposite materials. The rubberwood as a supportingmaterial wasdelignifiedbytwo-stepchemical treatment;impregnatingin NaOH/Na2SO3solution for 2, 4, and 6hfollowed byH2O2solutionfor 2 h. The results show that the most effective impregnating process involved a 6htreatment in NaOH/Na2SO3solution followed by 2hin H2O2solution.Moreover, whenthedelignifiedrubberwood was driedusing freeze drying, it achieved a higher impregnating efficiency of approximately 32% compared to vacuum oven drying, which yielded the maximum impregnating efficiency.The SEM analysis demonstratesthat the cell wallsof delignifiedrubberwoodare thinner compared tounmodifiedrubberwood.Additionally, the delignified rubberwood prepared through freeze drying exhibited fully filled pores with the PCM, whereas the delignified rubberwood prepared through vacuum drying only had partially filled pores with the PCM.The FT-IR spectraalsoprovidesfurther confirmation of the impregnation of PCM into the rubberwoods, thereby indicating the promising potential of rubberwood as a wood/PCM composite material.