Effect of antiaging agents on the outdoor natural weathering of bamboo powder/polypropylene foamed composites

Abstract

The effect of outdoor natural weathering on the properties of injection molded 33 wt% bamboo powder (BP)=polypropylene (PP) foamed composites with and without the antioxidant and hindered amine light stabilizers (HALS) were investigated. The composites containing the antiaging agents had higher color stability, slightly greater retentions of flexural modulus, tensile and notched impact strengths, higher creep resistance, and better rheological stability than the reference composite. The antiaging agents of pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) and poly-(n-hydroxyethyl-2,2,6,6-tetramethyl-4-hydroxy-piperidyl succinate) had more beneficial effect than n-octadecyl-b-(4-hydroxy-3,5-ditert-butyl-phenyl)-propionate and bis(2,2,6,6-tetramethyl-4-piperidinyl)sebacate. After 12 months of exposure, ᭝E* decreased from 22.8 of the reference composite to 9.9 of the composite with the antiaging agents. Rheological behavior results indicated that the storage modulus, complex viscosity, and non-Newtonian fluid index of composites containing the antiaging agents were slightly increased. Natural weathering caused less decreases in the storage and loss moduli, crossover modulus, relaxation time, and average molecular weight for composites containing the antiaging agents than those for the reference composite. Environmental scanning electron microscopy (ESEM) observation confirmed the improved surface durability for composites containing the antiaging agents.

Bamboo lumber – an innovative sustainable raw material and an accelerated weathering study for establishing its durability

“…Bamboo is excellent natural composite material; but poor in durability and requires special coating to enhance the life in exterior condition. Bamboo and their composites can be protected against weathering, and the preservative and finishing treatments can improve its durability like wood (Asif, 2009;Williams, 2005;Liu et al, 1994;Hung et al, 2012;Zhou and Huang 2016). Yu et al, 2021 investigated the discoloration and degradation of Bamboo under Ultraviolet Radiatio.…”

Effect of nano TiO2 on the cellular structure and mechanical properties of wood flour/polypropylene composite foams via mold‐opening foam injection molding

“…[3][4][5][6][7] And these products can potentially be developed as energy absorbing materials, which are extensively used in automotive, building, packaging and other industries. [8][9][10] Recently, foaming technology using supercritical fluid (typically CO 2 and N 2 ), an ideal and environmental-friendly method, has received broad consideration for the fabrication of microcellular WPCs via extrusion and injecting molding. [11][12][13][14] As a common molding method used in the production of polymer materials, injection molding produce polymer products with complex shapes through a simple, one-step, highly efficient, and low-cost molding process.…”

“…The introduction of a microcellular structure can greatly reduce the polymer density and improve its ductility and impact resistance, thus achieving the effects of both lightweight and high strength WPC products 3–7 . And these products can potentially be developed as energy absorbing materials, which are extensively used in automotive, building, packaging and other industries 8–10 . Recently, foaming technology using supercritical fluid (typically CO 2 and N 2 ), an ideal and environmental‐friendly method, has received broad consideration for the fabrication of microcellular WPCs via extrusion and injecting molding 11–14 …”

Exterior and under glass natural weathering of hemp fibers reinforced polypropylene biocomposites: Impact on mechanical, chemical, microstructural and visual aspect properties

“…Although they present lower mechanical performances than reinforced polymer composites glass fibers, their specific mechanical properties are excellent. Composites based on thermoplastics such as polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC) or polylactic acid (PLA) are widely used in modern society [2][3][4] at which the global production of PP is about 60 million MT per year and may reach 75 million MT in 2022 [5].…”