Potensi Kertas Putih Bekas sebagai Pengisi di dalam Komposit Polietilena Densitas Rendah (LDPE)

Abstract

This research is aimed to investigate waste white paper (WWP) potency as filler in low density polyethylene (LDPE) composites. LDPE/WWP composites are made by adding WWP particle with different size and loading with LDPE matrix in Z-blade mixer at180 oC and 50 rpm for 25 minutes. The effect of WWP loading and size on mechanical properties, surface morphology and thermal LDPEAMWP composites were investigated. The results of mechariical test showed that increasing of WWP loading to 40o/o has increased tensile strength about 30,9o/o and Young's modulus about l78,6yo to blank composite but decreased elongation at break LDPEAMWP composites. The LDPE/WWP composites with particle size of 3l pm have higher tensile strength, elongation at break and Yorurg's modulus than LDPEA^/WP composites with paticle size of 77 am equal to 7yo. Analysis of thermogravimetry (TGA) exhibited that increasing of WWP loading to 40oA increased thermal stability resistance LDPE VWP composites with inueasing temperatr.re until 600 oC, while Differential Scanning Calorimetry @SC) showed the increasing glass transition temperature (T) and melting temperature (Td LDPEAMWP composites, but degree of crystallinity ()[) decreased. Thermal analysis result is indicates that composites with particle size of 3l pm show higher thermal stability and degree of crystallinity compared composites with particle size af 77 pm. Scanning Electron Microscopy (SEM) of tensile fractured surface indicated that WWP with size of 3l pm better interaction with LDPE plymer matrix compared WWP with particle size of 77 pm. A compatibilizer, maleic anhydride plyethylene (MAPE) 3% was used to improve mechanical properties of composites. At similar loading of WWP (10,20,30 and 40 php), LDPEAtrIWP composites with MAPE showed higher tensile strengtlu Young's modulus, thennal stability, glass transition temperature (TJ and degree of crystallinity Q[) but lower elongation than composites without MAPE. Morphology test on tensile surface fractured with SEM and FTIR spectrum analysis for LDPENIWP composites with MAPE compatibilizing agent addition revealed existence of interaction between compatibilizer MAPE and WWP filler.