Water-Repellent Improvement of Green Composite Sheet Surface by Hydrophobic Modified-Silica Coating

The phenomenon of hydrophobic surface (contact angle of a water droplet exceeding 90°) has attracted a considerable research interest from academia and industry. Current studies have unveiled the fact that the hydrophobicity of a solid surface is governed by surface free energy and surface roughness. To date, many methods have been proposed for fabricating hydrophobic surfaces. In this paper, a facile, low cost, and time-saving approach for the improvement of water-repellent property of durian peel composite sheet surface is studied. A unique mixture of hydrophobic modified-silica particles and polystyrene was synthesised and applied onto the composite sheet via dip coating method. The hydrophobic property was characterised using scanning electron microscopy (SEM) and water contact angle meter. Results show that a water repellent surface with a contact angle of 143.90° was generated, which is nearly superhydrophobic. This method could be an effective strategy for producing hydrophobic surfaces for promising potential applications in water repellency, self-cleaning, friction reduction, and antifouling

Scutellaria galericulata L. (BR0000010183038)

Belgium Herbarium image of Meise Botanic Garden

Characterization on Thermal And Mechanical Properties of Non-Covalent Polyethyleneimine Wrapped on Graphene Nanoplatelets Within NR/EPDM Rubber Blend Nanocomposites

This study focused on the characterization of Natural Rubber (NR)/Ethylene Propylene Diene Monomer (EPDM) filled Graphene Nanoplatelets (GNPs) nanocomposites. The effects of GNPs non-covalent surface treatment using polyethyleneimine (PEI) and different loading of filler addition (0.25-5.00 wt. %) to cure characteristics, thermo-mechanical and thermal degradation properties of produced NR/EPDM rubber blends nanocomposites were analyzed and inter-correlated with their fracture morphologies. The surface treatment of GNPs was found to enhance the fillermatrices interaction in the NR/EPDM blend nanocomposites compared with unfilled and untreated GNPs filled NR/EPDM systems at similar loadings. The nanocomposites with 3.00 wt. % of PEI-treated GNPs possessed outstanding mechanical properties compared with unfilled NR/EPDM blends and filled nanocomposites without treatment (tensile strength of 27.78 MPa, 19.65 MPa and 23.34 MPa; respectively). The results were supported with thermal and dynamic analyses. Highly homogeneous dispersion of GNPs nanofillers and the presence of strong interfacial interaction between the matrix and reinforcement nanofiller resulted in an excellent thermal-mechanical properties of nanocomposites filled with 3.00 wt. % PEI treated GNPs. Obvious fractured morphological changes due to the noncovalent treatment provided hints on the role of GNPs treatment in improving the NR/EPDM blends mechanical and thermal properties

EFFECT OF DIFFERENT COOKING TEMPERATURE AND ALKALINITY ON MECHANICAL AND MORPHOLOGICAL PROPERTIES OF COMPOSITE SHEET FROM DURIAN SHELL WASTE FIBRE

Temperature and alkalinity are the critical factors that contribute to the successful of soda pulping. These factors influence the length size and interfibre bonding of the fibre. In this paper, durian (Durio zibethinus Murray) shell composite sheet were prepared by conducting chemical pulping through soda method to study the effect of different pulping temperature and % of NaOH on the mechanical and morphological characteristics of durian shell composite sheet. Six sets of composite sheet were produced from six sets of pulping. The pulping processes were conducted at 140, 160 and 170°C with 17, 19 and 21% of active alkali. The mechanical properties of the durian shell composite sheet were analyzed through few standard TAPPI analyses which are tensile, tear, burst, folding endurance and paper bulk thickness. The results show that the highest reading of paper bulk thickness, tensile, tear and burst index, and also folding endurance were achieved at the pulping condition of 170°C with 21% of NaOH with the value of 1.3366 g/cm3, 54.151 NM/g, 6.648 m.Nm2/g, 2.517 k.Pam2/g and 170 no. of fold, respectively. Scanning electron microscopic analysis showed that morphological changes took place depending on the size and arrangement of the fibres in the composites sheet