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Sulfonation of polymers is of great importance for the packaging industry mainly due to its effect on the alteration of surface functionality of polymer films. In this study we customized liquid phase sulfonation of low-density polyethylene (LDPE) swelling the polymer by using a combination of polar and nonpolar solvents. Swollen polymer was treated with sulfuric acid of varying concentrations with continuous mixing for in-depth sulfonation of the polymer. Presence of cyclohexane and ethanol, as polar and nonpolar reagents, not only kept the batch under isothermal conditions but also homogenously influenced indepth functionalization of LDPE. The durability of the sulfonated polymer was determined by grinding the test samples 30 days after the reaction. Fourier transforminfrared spectroscopy indicated presence of functional group moieties, which is also supported by increase of 5% and 1.35% in density and sulfur contents of the polymer, respectively. Contact angle measurements indicate 30 decrease in values of the sulfonated polymer which corresponds with decrease in carbon to hydrogen ratio (from 5.9 to 5.3) and increase in sulfur to carbon ratio (up to 0.0184) resulting from the sulfonation of the polymer. Differential scanning calorimetery results indicate almost linear reduction in the crystallinity of LDPE with an increase in acid concentration used for the sulfonation reaction., INTRODUCTION Imparting certain functional properties is of considerable advantage in polymers and it is a normal industrial practice for the surface treatment of polyethylene films for this purpose [1-3], Several [...]

The hybrid hydrothermal carbonization and ultrasound technology (HHTC‐Us) efficiently utilizes the function of both ultrasounds‐assisted and hydrothermal carbonization for hydrochar production. The HHTC‐Us of oil palm residues plays an essential role in hydrochar production. Hydrochar is a carbon‐rich material potentially produced from oil palm biomass, which has gained great interest due to its unique properties. Four main topics were highlighted: the production of crude palm oil and impacted biomass residue generation, properties and potential values of oil palm biomass conversion as hydrochar, hybrid hydrothermal carbonization reaction routes, and processing parameters that affect the HHTC‐Us technology. The review elucidates the promising production process or modification of hydrochar from oil palm biomass residues through hybrid technology. The technology potentially enhanced sustainability, creating challenges and new opportunities. [ABSTRACT FROM AUTHOR]

Phase change material (PCM) has been recognized as one of the important element in the energy storage and conservation management. PCM and its combination has been widely used in many applications and significant number of literatures has been published to highlight the potential use of PCM as thermal energy storage (TES) material. However, although the information is quantitatively enormous and the application of waste has becoming a trending subject nowadays, documented researches on PCM material derived from waste material are still very scarce. Therefore, in this paper, in-depth reviews on the implementation of potential waste materials in PCM considering its purposes in improving the TES performance, economic values and environment were reviewed and elaborated. Overall, this review shows potential utilization of waste materials as a new material substitute to produce an efficient, cost-effective and environmentally friendly PCM in the future TES system. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the contribution of multiwalled carbon nanotubes (MWCNTs) was studied for the evaluation of the performances of polyalkyd-based films produced from dehydrated palm oil. Initially, different percentages of MWCNTs, including 0.5, 1.0, and 1.5 wt %, were considered for loading into the resin with the help of sonication. Additionally, a 1.0 wt % loading was considered for in situ conditions during the esterification process to achieve better dispersion and obtain improved properties of the film. The loading was evaluated by different performance tests, such as those of tensile, elongation, pencil hardness, swelling ratio, gel content, wettability, chemical resistivity, adhesion, and surface morphology. The results of mechanical testing showed that the addition of 1.0 wt % MWCNTs enhanced the tensile strength by 50%, whereas in situ conditions were found to be favorable for significantly improving the tensile strength by 75%. Moreover, the wettability, surface morphology, and thermal properties were also found to be in favor of in situ conditions for the dispersion of the MWCNTs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42934. [ABSTRACT FROM AUTHOR]

Recently, the use of controlled release fertilizers in agriculture has resulted in huge benefits in plant growth and cultivation. Superabsorbent polymer (SAP)‐coated fertilizers have the added advantage in retaining water in soil after irrigation and also reduce the nutrient release rate from soil in a controlled manner. This study aimed to produce a nitrogen–phosphorus–potassium (NPK) fertilizer coated with superabsorbent carbonaceous microspheres polymer (SPC) by inverse suspension polymerization method with water‐retention and controlled release properties. Two sets of experiments were conducted: (1) three different weight percentages and (2) different materials. NPK coated with SPC showed increasing water‐retention ability with respect to carbon microsphere percentages and retains >80% water at the 30th day of experiment compared with pure NPK and NPK coated with SAP. The slow release behavior of all samples was investigated by induced coupled plasma mass spectrometry spectrometry and results showed that NPK coated with SAP and SPC has a low release rate with <50% nutrient release compared with uncoated NPK at the 30th day. The release mechanism kinetics of NPK coated with SAP and SPC were studied based on the Kosmeyer–Peppas model. The mechanisms approached Fickian diffusion‐controlled release as the n value for both samples was less than 0.5. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48396. [ABSTRACT FROM AUTHOR]