Superabsorbent polymer was prepared by graft polymerization of acrylic acid onto the chain of carboxymethyl cellulose. This superabsorbent polymer was further treated by the solvent precipitation method. We found that the water absorption rate of the treated polymer was greatly increased and the microstructure of the treated polymer was changed from close-grained structures to loose macropores....

Phase separation simulation study related to cellulose acetate-water-acetone has been done. Results show that porous asymmetric and symmetric membranes can be produced by changing the nonsolvent concentration or by the drying conditions without altering the polymer content using dry-casting process. Dry-casting process is the process in which complete evaporation of solvent and nonsolvent takes...

The microstructure of conjugated polymers is heterogeneous on the length scale of individual polymer chains, but little is known about how this affects their electronic properties. Here we use scanning Kelvin probe microscopy with resolution-enhancing carbon nanotube tips to study charge transport on a 100 nm scale in a chain-extended, semicrystalline conjugated polymer. We show that the disord...

Influences of process conditions on microstructure and dielectric properties of ceramic-polymer composites are systematically studied using CaCu3Ti4O12 (CCTO) as filler and P(VDF-TrFE) 55/45 mol.% copolymer as the matrix by combining solution-cast and hot-pressing processes. It is found that the dielectric constant of the composites can be significantly enhanced-up to about 10 times - by using ...

In this work, we studied propylene polymerization using some α-diimine palladium catalysts with systematically varied ligand sterics. In propylene polymerization, the ligand steric effect exhibits significant variations on the catalytic activity, polymer molecular weight, and branching density. However, the regio control for the polymer microstructure is poor. Furthermore, copolymerization of 1...

Guidance in a liquid core is possible with microstructured optical fibers, opening up many possibilities for chemical and biochemical fiber-optic sensing. In this work we demonstrate how the bandgaps of a hollow core microstructured polymer optical fiber scale with the refractive index of liquid introduced into the holes of the microstructure. Such a fiber is then filled with an aqueous solutio...

Here we describe a method of patterning electroluminescent (EL) polymers using micromolding in capillary (MIMIC). MIMIC is the one of the lithographic methods based on the microfludics among the soft lithography using a patterned poly(dimethylsiloxane) (PDMS) elastomer. The patterned microstructures of poly(dioctylfluorene) (PDOF), poly(p-phenylenevinylene) (PPV), and poly(2methoxy-5-2 0-ethylh...

Poly(2,5-Bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophenes (pBTTTs) are a new class of solution-processable polymer semiconductors with high charge carrier mobilities that rival amorphous silicon. This exceptional performance is thought to originate in the microstructure of pBTTT fi lms, which exhibit high crystallinity and a surface topography of wide terraces. However, the true lateral grain s...

This paper presents state-of-the-art micro and nano-fabrication techniques for biodegradable polymers. Replication molding, using a rigid or elastic master, can pattern structures on a polymer surface in a submicron resolution at a low cost. Layer-by-layer rapid prototyping methods are promising in producing controlled release units with complicated geometries, release mechanisms and the abilit...