Organocatalysts have attracted enormous interest in the water-crosslinking reaction in silane-grafted polyolefins (SGPOs) system owing to their simplicity, low toxicity and environmentally benign nature compared to organotin catalysts, which are most used in SGPOs system. We focus on organophosphorus compounds including four structure types as organocatalysts; phosphoric acids, phosphoric ester...

Mature oilfields usually encounter the problem of high watercut. It is practical to use chemical methods for water-shutoff in production wells, however conventional water-shutoff agents have problems of long gelation time, low gel strength, and poor stability under low temperature and high salinity conditions. In this work a novel polymer gel for low temperature and high salinity reservoirs was...

Water-soluble polymers provide an alternative to organic solvent requirements in membrane manufacture, aiming at accomplishing the Green Chemistry principles. Poly(vinyl alcohol) (PVA) is a biodegradable and non-toxic polymer renowned for its solubility water. However, PVA little explored processes due hydrophilicity, which reduces stability performance. Crosslinking procedures through esterifi...

Cell-encapsulating hydrogels used in regenerative medicine are designed to undergo a rapid liquid-to-solid phase transition in the presence of cells and tissues so as to maximize crosslinking and minimize cell toxicity. Light-activated free-radical crosslinking (photopolymerization) is of particular interest in this regard because it can provide rapid reaction rates that result in uniform hydro...

β-Nitroalcohols (βNAs) are promising corneoscleral crosslinking agents for the treatment of diseases such as keratoconus and myopia. Although it is believed that formaldehyde is released from the crosslinking reactions of βNAs, the mechanism by which βNAs react with amine-functionalized polymers has yet to be known. In this study, we present the reaction mechanism of the βNA crosslinking. Fouri...

Article history: Received January 26, 2013 Received in Revised form May 10, 2013 Accepted 20 May 2013 Available online 24 May 2013 Superabsorbent hydrogels based on poly(vinyl alcohol) were prepared by a crosslinking technique using glutaraldehyde as a crosslinker. The hydrogel structure was confirmed using scanning electron microscopy (SEM). Results from SEM observation showed a porous structu...

The mechanism of morphological phase transitions was studied for rod-shaped supramolecular assemblies comprised of a poly(acrylic acid)-block-poly(methyl acrylate)-block-polystyrene (PAA(90)-b-PMA(80)-b-PS(100)) triblock copolymer in 33% tetrahydrofuran/water after perturbation by reaction with a positively charged water-soluble carbodiimide. Tetrahydrofuran solvation of the hydrophobic core do...

Elastin is a critical biochemical and biomechanical component of vascular tissue. However, elastin is also highly insoluble and therefore difficult to process into new biomaterials. We present a simple approach for synthesizing elastin-based materials from two commercially available and water-soluble components: alpha-elastin and a diepoxy crosslinker. Reaction pH was shown to modulate the degr...

Ring-opening metathesis catalysis has received little attention as a means to functionalize or crosslink biopolymers in water since the required catalysts are not usually stable under these conditions. However, biopolymer solubility suggests such a procedure. We show that Grubbs 1 and 2 generation catalysts (in emulsion) as well as a water-soluble Hoveyda-Grubbs catalyst can be applied to cross...