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Hydrophobization of hydrophilic jute fiber, is of great importance as it can expand the applications of jute fiber in many fields. This work reports the hydrophobization of jute fiber by high‐energy radiation treatment which is an easy, single‐step, economical, and environment friendly method. Surface wettability of hydrophilic jute fiber is tuned by attaching long chain hydrocarbon molecules, namely butyl methacrylate, octyl acrylate and lauryl methacrylate, using gamma radiation. Lauryl methacrylate is found to be the most suitable agent among the molecules used for generating desired extent of hydrophobicity. Important reaction parameters, namely total dose, dose rate, monomer concentration, and solvent composition are optimized to achieve the desired degree of modification, for imparting hydrophobicity. Mechanical and thermal analysis reveals that there is no considerable damage to the base structure of fibers during modification. Scanning electron microscopy (SEM) is supporting evidence of the intactness of fiber after modification. The successful grafting of jute fiber has also been evidenced by SEM. This lauryl methacrylate modified jute can separate oily toxic liquids from aqueous media. The modified jute fiber may get enhanced applications in various fields. [ABSTRACT FROM AUTHOR]

Polyurethane (PU) sponge is being used on a large scale now‐a‐days, but that generates environmental pollution as it is not bio‐degradable. Moreover, the PU recycling existing techniques face several problems, which are being addressed sincerely throughout the world. Here, we report an easy, scalable, environment‐friendly, economic, and high throughput technique for converting scrap PU sponge into a superabsorbent for wastewater treatment. This is a new strategy for recycling scrap PU foam. This conversion follows the modification of surface energy of the PU sponge and generation of tiny‐scale roughness by a single‐step electron beam (EB) radiation‐assisted covalent attachment of dodecyl methacrylate (DMA) onto the waste PU sponge. The effect of degree of modification on the surface wettability is studied. Important process parameters namely, total dose, DMA concentration, solvent composition, and so forth are systematically varied and optimized to achieve the required extent of modification (~30 wt%). This desired degree of modification is achieved at 30 kGy total dose and in 15 vol% DMA concentration and 15 vol% water content in the reaction mixture. Grafting yield is measured gravimetrically and successful grafting is further confirmed by Fourier‐transform infrared spectroscopy, surface wettability, and surface morphology. The recycled PU shows superhydrophobicity with very high water contact angle (152°). Now, the recycled sponge can remove major liquid components of wastewater, namely, toxic organic solvents, oily liquids, nonpolar solvent soluble dyes from water media with high absorption capacity (25–30 g/g) successfully. [ABSTRACT FROM AUTHOR]

Flax fibre reinforced polyolefin composite is a great interest of today's scientists. But the preparation of such composites with desired properties is a great challenge due to the dissimilar surface wettability (surface energy) of polyolefin and flax fibre. In this work, we have developed a linear low density polyethylene (LLDPE)/flax fibre based composite successfully. First, flax fibre is subjected to gamma radiation-assisted surface modification through covalent attachment of long chain hydrocarbon. Therefore, the surface wettability of flax fibre turns closer to that of LLDPE, and consequently a LLDPE/flax fibre composite with a strong interface is formed easily. Due to the designing of strong interface and consequently higher load transferring capability, properties are improved considerably. Young's modulus and tensile strength values of composites with surface modified flax fibre become considerably higher compared to pure LLDPE and LLDPE/pure flax fibre composites. Strong reinforcement is reflected in the dynamic mechanical properties also. The highly improved dispersion and strong interfacial strength of LLDPE/modified flax fibre are observed in SEM (scanning electron microscopy). Thermal degradation temperatures of LLDPE and flax fibre are also improved in the composites. [ABSTRACT FROM AUTHOR]

ABSTRACT To observe the effect of ENGAGE (a poly-olefin elastomer) on compatibilization of industrially important incompatible blend, high-density polyethylene (HDPE)/ethylene-propylene diene elastomer (EPDM), 15 wt % ENGAGE is incorporated into the system and the latter is found satisfactorily efficient as compatibilizer for the above system. To improve some industrially pertinent properties another strategies are also followed in addition, incorporation of magnesium hydroxide [Mg(OH)2] and electron beam (EB) crosslinking into the system. The gel content was found to increase with radiation dose, EPDM content and Mg(OH)2 dispersion. ENGAGE interestingly increases the gel content that is, promotes crosslinking. It is unique that filler dispersion and crosslinked network formation maintain the compatibility of the ternary system, which is confirmed by X-ray diffraction, differential scanning calorimetry, mechanical properties, and scanning electron microscope. The compatibilization, Mg(OH)2 dispersion, and EB crosslinking improve the mechanical, thermo mechanical, flame retardant properties, and phase morphology considerably. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44922. [ABSTRACT FROM AUTHOR]

Controlled (low degree) grafting of a polar group to a non-polar polymer or reverse is an important means to change the polarity of the base polymer, maintaining the properties of the polymer. In the present study, a polar monomer, methacrylic acid (MAA), was grafted onto three different types of 'Engages' (a special type of polyolefin elastomer) in aqueous medium by gamma radiation. Grafting parameters (total dose, MAA concentration, and Mohr's salt concentration) were optimized for the desired amount of low-degree grafting (less than 15 wt%). The grafting yields were measured gravimetrically. Pure and grafted Engages were characterized by Fourier transformed infrared spectroscopy, contact angle measurement, and scanning electron microscope. Fourier transformed infrared spectroscopy spectra confirmed the successful grafting of MAA onto the Engages. For all three, the best yields were found at 3-kGy gamma radiation dose, 25-vol% MAA, and 20-mM Mohr's salt concentration. The grafting efficiencies follow a descending trend like Engage 8150 > Engage 7447 > Engage 8003. From contact angle measurement, it was seen that the hydrophilicities of all Engage surfaces were increased after grafting. Scanning electron microscope illustrated the best distribution of grafted MAA molecules to be on Engage 8150 surface followed by Engage 7447 and Engage 8003, respectively. The tensile testing results suggested that the mechanical properties of the base polymers remained almost unchanged after grafting. Thus, without detrimenting any basic properties, polyolefin elastomers can be grafted to achieve desired yield by an environmental-friendly method, gamma radiation grafting, in aqueous media. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]