On the influence of ion-plasma treatment on the surface properties of reinforcing fillers

This article presents the results of a study of the hydrophilic properties of VMPS-10 84x4 glass filaments and SYT-49S 12K carbon tows. It has been found that the contact angle of glass and carbon fibers, which decreases after ion-plasma treatment, returns to its original values within 8 days. The capillarity values of both types of fibers increase irreversibly, but for carbon fibers, we observe a more significant change in this parameter. In the course of studying the microstructure of the surface of filler fibers before and after processing, it was found that all samples were uniformly covered with a film of an active lubricant with a microdispersed structure; however, for glass fibers, the size of the sizing particles increased during processing, and for carbon fibers, it decreased. In addition, thermophysical studies of the used reinforcing fillers were carried out, and it was found that during the ion-plasma modification, the erosion of the sizing film occurred.

INCREASING PRODUCTION WEIGHT OF MODIFIED-BIOSILICA FROM RICE HUSK AND ITS APPLICATIONS AS REINFORCING FILLER IN RUBBER FINISHED GOODS

Biosilica from rice husks has a potential that can be used as a reinforcing filler in the production of rubber finished goods displace mine silica. But it’s difficult to disperse homogenetically into a rubber finished goods, so it needs to modify the surface using a coupling agent sign. The capacity for the production of modified-biosilica would need to be at a great level to meet the needs of the rubber industry. The purpose of the research is to identify the characteristics of the modified-biosilica by silane TESPT (bis-(3-triethoxysilylpropyl) tetrasulfane) that resulted from increasing the weight of biosilica in the production process and the application as reinforcing filler on the rubber. Increasing of weight in the production process was done gradually on a scale of 0.5; 1; 2; and 5 kg of biosilica per process using a mixer-propeller. The technique on surface modifications was using a one-step modification (OSM) and two-step modification (TSM). Surface modification treatment using TESPT has increased the uniformity of the particle size distribution of the biosilica. Unmodified-biosilica has an average particle size of 717.1 nm (PDI 0.600), while modified-biosilica has an average particle size of 574.6 nm (PDI 0.585). Applications for reinforcing filler in the soles rubber industry are performed in PT Triangkasa Lestari Utama. Research indicates that increasing the weight of biosilica on the surface modifications did not significantly affect the density, lightness, crystallinity, and purity. The applications as reinforcing fillers have increased the quality of rubber finished goods compared with unmodified-biosilica. The best rubber finished goods quality approaching shoes-sol standards is a product that used modified-biosilica by OSM technique. This rubber finished goods has a tensile strength of 5.80 MPa, elongation at break of 425%, tear strength of 23.25% and abrasion resistance of 251.5 mm3 .

Nanocellulose Xerogel as Template for Transparent, Thick, Flame-Retardant Polymer Nanocomposites

Cellulose nanofibers (CNFs) have excellent properties, such as high strength, high specific surface areas (SSA), and low coefficients of thermal expansion (CTE), making them a promising candidate for bio-based reinforcing fillers of polymers. A challenge in the field of CNF-reinforced composite research is to produce strong and transparent CNF/polymer composites that are sufficiently thick for use as load-bearing structural materials. In this study, we successfully prepared millimeter-thick, transparent CNF/polymer composites using CNF xerogels, with high porosity (~70%) and high SSA (~350 m2 g−1), as a template for monomer impregnation. A methacrylate was used as the monomer and was cured by UV irradiation after impregnation into the CNF xerogels. The CNF xerogels effectively reinforced the methacrylate polymer matrix, resulting in an improvement in the flexural modulus (up to 546%) and a reduction in the CTE value (up to 78%) while maintaining the optical transparency of the matrix polymer. Interestingly, the composites exhibited flame retardancy at high CNF loading. These unique features highlight the applicability of CNF xerogels as a reinforcing template for producing multifunctional and load-bearing polymer composites.

Improving the Mechanical Ductility and Toughness of Injection-molded Polylactide Pieces by the Dual Incorporation of Liquor Waste Derived Spent Coffee Grounds and Oligomers of Lactic Acid

This work puts the Circular Bioeconomy’s concept into action, originally valorizing residues from the beverage liquor coffee industry into reinforcing fillers for green composites of polylactide (PLA). The as-received spent coffee grains derived from liquor waste were first milled to obtain the so-called spent coffee grounds (SCGs), which were then incorporated at 20 wt.% into PLA by extrusion. With the aim of improving the compatibility between the biopolyester and the lignocellulosic particles, two oligomers of lactic acid (OLAs), namely OLA2 and OLA2mal, being the latter functionalized with maleic anhydride (MAH), were both added during the extrusion process at 10 wt.%. The resultant compounded pellets were finally shaped into pieces by injection molding for characterization. Results showed that, as opposite to most claims published in the literature of PLA composites based on lignocellulosic fillers derived from soluble coffee wastes, the incorporation of liquor waste derived SCGs increased the ductility of the pieces by nearly 280% due to their high coffee oil content. The incorporation of OLA2 and OLA2mal contributed to improve the impact strength of the pieces by approximately 6% and 12.6%, respectively. The higher performance of OLA2mal was ascribed to a reduction of crystallinity in the green composite due to the chemical interaction by the MAH groups. However, the incorporation of SCGs into PLA slighlty reduced the thermal stability and yielded a dark-to-brown color, whereas it also delayed the disintegration rate of the pieces in controlled compost soil. Therefore, the results attained herein open up novel opportunities for the development of green composites of PLA with higher ductility and toughness through the valorization of liquor coffee wastes.

Research On the Effect of Reinforcing Filler on The Mechanical and Electrical Properties of Insulating Coated Silicone Rubber

This paper studies the silicone rubber insulation coating material used for the modification of overhead bare wires. The influence of two reinforcing fillers of silicone rubber on the density, mechanical properties and electrical properties of insulating coating materials was explored. Finally,25 copies of white carbon black were selected as a reinforcing filler to prepare a low-density, high-strength, and good insulating silicone insulating coating material.

PRODUCTION AND CHARACTERIZATION OF RICE STARCH AND CORN STARCH BASED BIODEGRADABLE BIOPLASTIC USING VARIOUS PLASTICIZERS AND NATURAL REINFORCING FILLERS

The present study focuses on testing the potential of starch from two different sources: corn and rice, to produce bioplastics, and the impact of natural agricultural waste materials (eggshells and rice hulls) as fillers. Bioplastic samples with different starches, plasticizers and amounts of fillers, in varying combinations, were prepared to determine the feasibility of the produced bioplastics. The physico-chemical properties of the bioplastics, such as moisture content, water absorption, water and alcohol solubility, biodegradability, tensile strength and Young’s modulus, were investigated. FT-IR analysis was also performed. The RTV silicone coating of the samples was tested to induce hydrophobic properties to water-soluble bioplastics. This study demonstrated that the utilization of starches from different sources, various types of plasticizers, as well as filler types and amounts, can have a significant impact on the physico-chemical properties of the bioplastics. Moreover, the bioplastics produced are safe for the environment and biodegradable, so starch-based bioplastics can be a promising environmentally friendly alternative to harmful petroleum-based plastics.