Lavender oil- (LO-) loaded ultrafine nanoparticles (NP) ( diameter < 50 nm ) of a copolymer were used for impregnating fabrics of cotton, cotton polyester, and polyester-elastane. The copolymer was composed mainly of methyl methacrylate (MMA) units with a low proportion of methacrylic acid (MAA). Moreover, two kinds of NP were used: one containing uncrosslinked copolymer and another one composed of crosslinked material. All the fabrics impregnated with NP of uncrosslinked copolymer keep the aroma up to 25 washes. Under storage at ambient conditions, the fabrics impregnated with NP of either uncrosslinked or crosslinked copolymer emitted aroma for up to almost 60 days. The long duration of aroma emission from fabrics is attributed to ease of the small nanoparticles used in this study of penetrating and staying inside the pores of the fabric fibers.
The influence of residual wax content on the thermal, rheological, and mechanical behavior of two high‐density polyethylene (HDPE) samples from different lots of the same supplier was characterized. HDPE with a low wax content presented a higher melting temperature and a wider melting endotherm. A decrease in the degree of crystallinity and thermal stability of HDPE with a higher wax content was observed. Thermograms obtained by DSC indicated a small additional exothermic transition associated with the exclusion of residual wax. A higher wax content in HDPE produces a decrease in its viscosity due to a lubricating effect, which allows the sliding of HDPE chains of high molecular weight. In contrast, HDPE with lower wax content achieves greater elongational viscosity and melt strength. The mechanical testing results show that HDPE with higher wax content presented lower Young's modulus, tensile strength, elongation at break, and Izod impact strength than HDPE with lower wax content. The results obtained show that a relatively slight difference in wax content significantly affects HDPE properties.
The effect of different carbon structures on the properties of low density polyethylene film and linear low density polyethylene blends (LDPE/LLDPE) subjected to artificial weathering, was studied. The carbon structures used were carbon black (CB), multi wall carbon nanotubes (MWCNT) and Graphene nanoparticles (GNP), at various loadings: 0.05, 0.1, 0.3, 0.5, 1.0, and 2 wt%. The PE-Carbon structure composite films were characterized by optical microscopy (MOP), Haze, visible light transmission, UV-visible, thermogravimetric analysis (TGA), melt flow determinations (MFI) and tensile properties. Weathering measurements were evaluated in a QUV panel chamber with UV fluorescent lamps. The films degradation was analyzed following the change in carbonyl index of FTIR spectra, mechanical properties, and molecular weight. A noticeable better dispersion of CB and CNT particles in polyethylene matrix was observed compared with GNP. MWCNTs and CB produced high Haze and low visible light transmission. Thermal stability measured by TGA increased with the presence of GNP and CB. The crystallinity, melting, and crystallinity temperature (T m and T c ) of the polymers increased with MWCNT and GNP. All the films with carbon structures presented an increase in the modulus of elasticity, with CB giving the highest elastic modulus. Artificial weathering of films with carbon structures showed that CB particles and CNT provided the highest UV protection to polyethylene, with a noticeable increase in low molecular weights and a retention in tensile strength and elongation at break which was reflected in maintaining their flexibility. Films with CNT showed the least significant changes in their properties, being more resistant to photo-degradation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.