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Conventionally, panel boards are produced with material flex or microparticle with P.U. or U.F. as adhesives. However, in this study, nanoparticle with epoxy resin as an adhesive was used to produce nanoboard. Coconut shell nanoparticle composite with epoxy resin as an adhesive was prepared using a compression molding technique. The coconut shell particles were originally 200 mesh size and then milled mechanically with a ball mill for the duration of 10, 20, 30, and 40 h (milling times) to produce nanoparticles. The composition ratio of the composite is 85 vol.% of coconut shell and 15 vol.% of epoxy resin. The formation of nanoparticles was observed with transmission electron microscopy (TEM). The mechanical, physical, and microstructure properties of the composite were examined with X-ray diffraction, scanning electron microscopy, atomic force microscopy, and universal testing machine. The results established that the properties of the composite (microstructures, mechanical, and physical) are influenced by the duration of milling of coconut shell particles. The modulus and flexural strength of the composite improved with an increase in the milling time. The density, thickness swelling, and porosity of the composite were also influenced by the milling times. The result suggested that the composite properties were influenced by the particle size of the coconut shell. The coconut shell nanoparticle composite can be used in the manufacturing of hybrid panels and board.

The purpose of the study was to determine the effect of the application of Project Based Learning (PjBL) on creative thinking skills (CTS) and student learning outcomes on vibrations and waves. The approach and design used were Quasi Experimental and the one-group posttest-pretest. Purposive sampling technique has been used to select 2 classes of research samples, namely class VIII-A (control) and VIII-B (experiment) high school students. Data collection on CTS and student learning outcomes (LO) using a test instrument in the form of multiple choice questions developed by the researcher. The data analysis used the normalized N-gain score formula and the percentage formula. The results of the data analysis show that the PjBL learning model can improve the CTS of the experimental class students with a high category compared to the control class. Student learning outcomes through the PjBL learning model show better than through non-PjBL. The conclusion in this study is that the PjBL model can improve creative thinking skills and student learning outcomes.

Coconut is one of the abundant agricultural products in Indonesia. Coconut shell is one of the wastes from coconut products that can be used as biocomposite material. The purpose of this study was to find out the effect of ball milling time on the chemical properties of coconut shell powder. X-ray diffraction (XRD) and X-ray fluorescent (XRF) have been used in this study. Coconut shell powder 200 mesh was milled using mechanical ball milling for various milling times (20, 30, and 40 hours) at 350 rpm constant speed. The results of our study using XRD showed that the coconut shell powder contains SiO2, C, Fe2O3, CaO, K2O, and Al2O3. The intensity of the diffraction pattern from our sample increased when the ball-milling time was increased. This implies that the crystallinity of the sample was influenced by the ball-milling time. By using XRF, it was found that the coconut shell powder contains 13.6% of Fe2O3, 25.7% of CaO, 46.1% of K2O, 2.8% of CuO, and 8.2% of P2O5. The percentage composition of Fe2O3 increased from 13.6% for 0 hours milling time to 30.2% after the sample was milled for 20 hours. The percentage composition of Fe2O3 rose to 32.2% for the milling time of 40 hours. However, the percentage compositions of CaO and K2O decrease as the milling time is increased. The percentage composition of P2O5 is independent of milling time. Our results show that the chemical properties of coconut shell powder are influenced by the ball-milling time or particle size of coconut shell powder.

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