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Abstract This study used ethylene-propylene diene monomers (EPDM), an elastomer, to develop foams incorporating clay as filler using simple compounding, chemical foaming, and peroxide-mediated light crosslinking methods. The lowtemperature batch [...]

The present work focuses on the preparation of cellulose nanocrystals (CNCs) reinforced composites based on polyhydroxybutyrate (PHB) and polypropylene (PP). The effects of the CNCs content as reinforcement and the addition of maleic anhydride (MA) as a coupling agent on the mechanical and morphological properties of the composites were studied. In addition, the biodegradability of the composites was investigated. Samples were prepared using PP and PHB as matrixes and CNCs as reinforcement. Test samples were prepared using the injection molding machine. The studied parameters were microscopic analysis and tensile strength measurement. Tensile strength increased with increasing CNC, but it decreased slightly when 5 wt% of CNC was added. Tensile strength decreased with the addition of MA. Environmental impacts from the production of 100 g of PP and PHB were evaluated using the life cycle assessment (LCA) approach. The results showed that the environmental impacts of composites containing PHB biopolymer are higher than PP ones. KEYWORDS cellulose nanocrystals, injection molding, life cycle assessment, maleic anhydride, polyhydroxybutyrate, 1 | INTRODUCTION With increasing awareness of the consequences of fossil-based materials and increased demand for more environmentally friendly materials, the application of biobased composites has attracted more attention. Composites [...]

This research aimed to investigate the effect of pulping conditions and refining intensities of wheat straw to be recommended for fluff pulp production. For this purpose, mono ethanol amine (MEA) was selected as a de-lignification agent at three levels of 50:50, 25:75, and 15:85 (MEA/water, W/V %), and soda-AQ 14 W/V % was used as a reference pulping. To investigate the optimal refining intensity, the obtained pulp was passed through a single disk laboratory refiner from 0 to 6 times and in two different consistencies (1.5 and 2.5 W/V %). Total yield, kappa number, ash content, and the Schopper-Riegler (SR°) freeness of the prepared pulps were investigated. Finally, hand sheets with a targeted basic weight of 70 g/m2 were made according to the related standards. The hand sheets were characterized using Fourier transform infrared (FTIR) spectroscopy and a field emission scanning electron microscope (FE-SEM). Sheet density, brightness, and mechanical properties such as burst, tensile, and tear indices were also investigated. The FE-SEM photographs showed that the texture of the hand sheet became denser as the refining intensity increased. External fibrillation on the surface of the fibers was also observed, especially on those refined with 2.5% consistency. The results of the chemical composition of wheat straw indicated that wheat straw containing a high percentage of holocellulose is an excellent candidate for the production of fluff pulp. The total yield and kappa number of MEA pulps increased with the decrease in MEA concentration. FTIR results indicated the presence of a peak related to amino groups in the pulp related to MEA pulp. The results also indicated that the mechanical properties of the papers, except for the tear index, were enhanced as the intensity of refining and the pulp consistency during refining increased. [ABSTRACT FROM AUTHOR]

This study used ethylene‐propylene diene monomers (EPDM), an elastomer, to develop foams incorporating clay as filler using simple compounding, chemical foaming, and peroxide‐mediated light crosslinking methods. The low‐temperature batch mixer was employed for compounding azodicarbonamide (ADC) as a foaming agent, dicumyl peroxide (DCP) as a crosslinker, followed by compression molding for sheet preparation and the high‐temperature foaming process. Fourier transform infrared spectroscopy (FTIR) equipped with a hot stage attenuated total reflection (ATR) was employed to elucidate the ADC decomposition and foaming. The DCP (0.25 phr) content was optimized based on the foaming expansion ratio (>4) and stability, which was further optimized in conjuncture with clay to generate high‐performance composite foams. The incorporation of 1% organoclay enhances the expansion ratio and specific tensile strength by >7 and ~ 270%, respectively, compared with EPDM foams without clay while displaying a density of 0.11 g/cm3. Overall, the developed foaming process can be extended to other elastomeric polymers for various applications such as protective gears (e.g., helmets and shin guards), thermal/sound insulation, packaging/containment, footwear soles, oil absorption, etc. [ABSTRACT FROM AUTHOR]