The effects of aging time on indentation creep behaviors of Polymethyl methacrylate (PMMA) have been investigated and the creep displacement was found to increase with aging time. However, the rate of change weakens as aging time increases. The generalized Calvin model consists of three Voigt elements that provide a good description of the indentation creep behavior of PMMA during the holding stage

In this study, the novel ladder polymer (NLP) was syntheriszed and used as flame-reatardant additive for vinyl ester resin (VER). Two kinds of silane coupling agent was ultilized for fabrication of nLP then its characteristics were confirmed with help of nuclear magnetic resonance, Fourier transform infrared spectroscopy, X-ray diffractometry. The NLP based composites were fabricated at room temperature

This work reports the synthesis of poly (monomethyl itaconate) grafted multi-layer graphene oxide (PMMI-g-GO) by atom transfer radical polymerization using activators regenerated by electron transfer (ARGET-ATRP). PMMI-g-GO presents outstanding properties, such as a high electrical conductivity (5.04 Sm-1), low number of stacked graphene layers (6) and IG/I2D ratio of 2.05 estimated from Raman spectrum

A nondestructive method of evaluating the curing degree (crosslinking density) of cured rubbers and their nanocomposites based on attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was proposed and applied to fluorine-based rubber (FKM), in which triallyl-isocyanurate (TAIC) was employed as a curing agent. ATR-FTIR spectroscopy demonstrated that the C=O band in TAIC at 1699

The reclaiming process of ethylene-propylene-diene monomer (EPDM) using a twin-screw extruder was studied and the effect of reclaiming conditions including screw speed (40, 80 and 120 rpm) and reclaiming agent content (0, 1.5 and 3 phr) at 280 °C (barrel temperature) on swelling, curing, mechanical properties as well as stress relaxation of virgin EPDM/40 phr reclaimed rubber blends was evaluated.

In this paper the exploration of specific imprinted sorbent for 4-hydroxy-3-nitrophenylacetic acid (NHPA), an indicator of 3-nitrotyrosine, a biomarker of pathophysiological states, was described. The optimization of synthetic protocol, supported by theoretical studies, allowed to select NHPA imprinted poly(acrylic acid-co-ethylene glycol dimethacrylate) as the most specific polymer with imprinting

The pursuit of highly efficient phosphorous flame retardants for polymer-matrix composites is of great sense in industrial and academic community. In the contribution, a phosphorous-phosphorous (P-P) synergy between structurally well-defined phosphonium sulfonates (PhS) and triphenyl phosphate (TPP) or bisphenol A bis (diphenyl phosphate) (BDP) was specifically revealed in PC/ABS alloy. Compared with

This study aims to investigate the relationship between lignin content, morphology, and rheology of lignin containing cellulose nanofibers (LCNFs). The morphology and rheology of LCNFs were dominated by lignin content. Lignin content had two-sides on mechanical fibrillation. At high lignin content (23.79 %), reduced efficiency of defibrillation resulted in large LCNFs connecting with lignin patches

This work is focused on the modification of the interphase zone in short flax fibres / polypropylene (PP) composites by a bio-inspired modification of fibres called “nanostructuration” that uses the adsorption of biomass by-products, i.e. cellulose nanocrystals (CNC) and xyloglucan (XG), to create hierarchical flax fibres. The wettability and interfacial adhesion study reveals a strong decrease in

Abstract Hexamethylene diisocyanate (HMDI) reacts with 4-bromo-1H-pyrazole as a blocking agent to form blocked adducts of isocyanates. The adducts were characterized by FTIR, NMR, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). In the FTIR spectra, disappearance of a peak at 2250–2270 cm−1 is the indication of blocking of diisocyanate molecule with 4-bromo-1H-pyrazole

Natural rubber (NR) vulcanizates reinforced by carbon nanotubes (CNT, 3 phr), graphite particles (GP) and CNT/GP hybrid filler (varied GP 0–50 phr) were prepared. The stress relaxation behaviors of various filled samples were characterized by the novel temperature scanning stress relaxation (TSSR) technique to elucidate the state and degree of filler dispersion based on initial relaxation modulus,

In recent years, organic-inorganic hybrid materials prepared by the sol-gel method have gained considerable attention in various fields such as the optic and electromagnetic field, as well as in biomedical sciences. In this study, hybrid polymers composed of poly(ethylene glycol) (PEG) and titania with different molecular weights were prepared using the sol-gel method. Differential mobility analyzer

In this study controllability of morphology and wettability behavior of the polysulfone electrospun nanofiber mats (ENMs) by adding the surfactants was investigated. The effect of cationic, anionic, and non-ionic surfactants on diameter size, hydrophilicity or hydrophobicity, surface roughness, and chemical composition of the ENMs was studied using FESEM, contact angle measurement, AFM, and FTIR, respectively

Generating surface-functional microstructures is an effective way to enhance the bonding strength of metal and carbon fiber-reinforced polymer (CFRP). In this study, different microstructural morphologies consisting of two different patterns were generated on the aluminum alloy (A7075) surface via laser processing. The experimental results indicated that different microstructural morphologies contribute

This study aims to understand the effect of micro- and nanofibrillated cellulose (MNFC) on the tensile index, softness, and water absorbency of tissue paper. MNFC was produced from four different fiber sources. The results show that MNFC acts as an effective strength enhancer but with a reduced water absorbency and softness. The impact of the fiber source on MNFC manufacturing cost and the trade-off

This review summarizes the progress of transition metal catalyzed ethylene polymerization to ultra-high molecular weight polyethylene (UHMWPE), focusing on the catalytic activities of different post-metallocene systems, polymer properties, and experimental conditions used. The review time span is 2010-present time, 161 references.

Triboelectric nanogenerators (TENGs) are devices that convert external mechanical energy into electricity by combining the triboelectric effect and electrostatic induction. As a new mechanical energy harvesting system, TENGs have demonstrated high vitality and great advantage, which hold great promise for applications in various areas of the future society. Over the past few years, the exponential

Visible-light-driven photocatalysis is a robust technology for amending the negative effect of pollutants on the environment with a minimum energy use. Herein, we describe a simple approach to producing such a photocatalyst by coupling conjugated polyvinyl chloride (cPVC) with the TiO2 nanotube (TNT) thermolysis method. By activating peroxymonosulfate (PMS) to make a cPVC/TNT/PMS system using visible