Novel pH- and Temperature-Sensitive Behavior of Binary Graft DMAEMA/PEGMEMA onto LDPE Membranes

Abstract

Low-density polyethylene membranes (LDPEs) were modified by the mutual grafting of 2-(dimethylamino) ethyl methacrylate (DMAEMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMEMA) using a direct method with gamma-rays. The effects of absorbed dose and monomer concentration were determined. The grafted samples were confirmed by Fourier transform infrared spectroscopy, thermal properties were analyzed by differential scanning calorimetry and thermogravimetric analysis, and the stimuli-responsive behavior and critical pH point were studied by swelling determination and measurement of the contact angle in water. pH-and thermo-responsive membranes of LDPE-g-DMAEMA/PEGMEMA exhibited a low critical solution temperature of 40 • C and critical pH point around 7.5.

Comonomer effect: Switching the lower critical solution temperature to upper critical solution temperature in thermo‐pH sensitive binary graft copolymers

“…The main objective of surface modification is exploring more potential applications for hydrophobic materials that generally have limitations due to their lack of biocompatibility or their prone to bacterial adhesion . There are several ways to induce a surface modification; however, grafting‐radiation method is one of the most interesting and useful technique to modify a wide variety of polymers without need to use chemical initiator . The ionizing radiation energy helps to create free radicals over the entire surface, which then react with vinyl monomers forming polymer chains …”

“…[1][2][3] There are several ways to induce a surface modification; however, grafting-radiation method is one of the most interesting and useful technique to modify a wide variety of polymers without need to use chemical initiator. [4][5][6][7] The ionizing radiation energy helps to create free radicals over the entire surface, which then react with vinyl monomers forming polymer chains. [4][5][6][7][8] Stimuli-sensitive polymers are a class of polymers that can undergo a reversible phase transition as response to changes in their environmental conditions such as magnetic field, ionic force, light, pH, and temperature.…”

“…[4][5][6][7] The ionizing radiation energy helps to create free radicals over the entire surface, which then react with vinyl monomers forming polymer chains. [4][5][6][7][8] Stimuli-sensitive polymers are a class of polymers that can undergo a reversible phase transition as response to changes in their environmental conditions such as magnetic field, ionic force, light, pH, and temperature. [5][6][7]9 Among all stimuli-sensitive polymers, thermoresponsive and pH-sensitive materials are the most studied by their promising applications as drug carriers.…”

Facile Synthesis of Cellulose Acetate Ultrafiltration Membrane with Stimuli‐Responsiveness to pH and Temperature Using the Additive of F127‐b‐PDMAEMA

“…With the increasing amounts of F127-PDMAEMA, the absorbance at 1740 cm 1 became weaker which is attributed to the increased amounts of F127-PDMAEMA in the membrane. [14,[41][42][43][44][45][46][47][48] The responsive mechanism of the membranes was explained in Figure 11. And this illustrated that the membrane surface chemical constitution had been changed.…”

Surface Modification of Polyester-Fabric with Hydrogels and Silver Nanoparticles: Photochemical Versus Gamma Irradiation Methods

“…Graft polymerization combines the features of the matrix, such as chemical and thermal resistance or specific mechanical properties, and introduces functional groups with advantageous new surface properties; this method is applicable for many substrates and combination of monomers and, unlike chemically initiated grafting, it does not require initiators, catalysts, or additives [16]. Moreover, the surface can be covered uniformly, and the polymer is sterilized by the radiation [17].…”