Photoinduced graft copolymerization of 2‐hydroxyethyl methacrylate on cotton cellulose in the presence of triethyleneglycol dimethacrylate

A surface photografting polymerization (k > 300 nm) of a multifunctional monomer which was trimethylolpropane triacrylate (TMPTA), was conducted with benzophenone (BP) as photoinitiator and LDPE as model substrate, in mixed solvents containing tetrahydrofuran (THF) and water. Proved by ATR-IR, highly crosslinked grafted layer was generated rapidly under UV irradiation. Effects on percent conversion of grafting are detailed with, such as feed ratio of BP to TMPTA, mass percent of TMPTA in the reaction system, mass percent of water in the mixed solvents and addition of the second monomer, methyl methacrylate (MMA). As both verified by SEM and AFM, relatively planar grafted layer was produced when photografting was carried out merely in THF; adding water in the reaction system caused the formation of ''craters'' in the grafted layer. In addition, effects of mass percent of water in the mixed solvents, UV irradiation time, TMPTA concentration and addition of MMA on the size, shape and quantity of the ''craters'' were investigated by SEM. A plausible mechanism for the formation of ''craters'' is also proposed.

Section: Introductionmentioning

confidence: 92%

Surface photografting polymerization of trimethylolpropane triacrylate onto LDPE substrate in tetrahydrofuran/water mixtures

Wang

Liu

et al. 2007

“…Studies of the accelerative effects of additives on grafting yields are of interest, as such effects can lead to lower doses of radiation being used in grafting experiments. Photografting of vinyl monomers on polyolefins,7–8 pure cellulose,9–11 and jute12–14 was considerably accelerated when small amounts of polyfunctional monomers, such as tripropylene glycol diacrylate (TPGDA) and trimethylol propane triacrylate (TMPTA), were added to the grafted formulations. Khan and colleagues15 improved the mechanical properties of jute yarn with an organometallic complex using ultraviolet (UV) radiation.…”

Section: Introductionmentioning

confidence: 99%

Surface modification of jute yarn by photografting of low‐glass transition temperature monomers

Sawpan

Khan

Abedin

2002

Jute yarns were grafted with three types of vinyl monomers of different functionalities such as methyl acrylate (MA), ethyl acrylate (EA), and 2-hydroxyethyl acrylate (HEA) with ultraviolet radiation. The graft copolymerization reaction between the cellulose of the jute fibers and the monomer and the chemical environment of the treated fibers were confirmed by Fourier transform infrared spectroscopy. The reduction of OH groups and increment of ϾCAO groups in treated jute yarns were observed. DSC studies showed that the treated jute fibers were more thermally stable compared to the untreated one. The surface topography of the yarns was analyzed by an environmental scanning electron microscope. Different parameters, such as concentration of monomers and irradiation time, were optimized with the extent of mechanical properties such as tensile strength and elongation at break of the jute yarn. MA, EA, and HEA produced enhanced tensile strengths of 87, 78, and 85%, respectively. The monomers MA, EA, and HEA showed improved elongations at break of 118, 91, and 76%, respectively. The water uptake of treated and untreated jute yarns were studied. The maximum water uptake was observed of the grafted sample compared to the untreated jute yarn. The effects of additives such as urea on mechanical properties were also studied.

Characteristics of methacrylic acid‐grafted polyethylene films prepared by photografting in the presence of polyfunctional monomers

Kubota

Kojima

Kuroda

2006

Photografting of methacrylic acid (MAA) on low-density polyethylene film (thickness ϭ 30 m), on which xanthone photoinitiator was coated earlier, in the presence of polyfunctional monomers such as N,NЈ-methylenebisacrylamide, ethylene glycol dimethacrylate, and trimethylol propane triacrylate was examined at 60°C in water/ acetone (3:1 v/v) mixture solvent. The photografting was retarded at the earlier stage of polymerization, and then accelerated when small amounts of the polyfunctional monomers (1-3 mol % of MAA monomer used) were added to the system. Addition of the polyfunctional monomers did not affect distribution of the grafted chains in the cross section of the resultant MAA-grafted PE film, which was measured by electron probe microanalysis. The MAAgrafted samples were subjected to adsorption of cupric ions at 25°C for 24 h in the system of pH ϭ 5. The adsorption was considerably suppressed for the grafted samples prepared at the earlier stage of polymerization in the system with the polyfunctional monomers. The phenomenon was discussed in terms of the formation of crosslinked and branched structures in the MAA-grafted chains depending on the polymerization stage in the system with polyfunctional monomers.