Agency for Science, Technology and Research

Decheng Wu

Ye Liu

Chaobin He

Xu Li

Jianwei Xu

Chee Leng Lay

A copolymer for modifying rheology is formed of monomer units consisting essentially of at least one first monomer unit comprising a polyhedral oligomeric silsesquioxane having an ethylenically unsaturated radical; at least one second monomer unit comprising an unsaturated oligo-poly(dimethyl siloxane)(meth)acrylate; and a sufficient amount of at least one unsaturated water-soluble monomer, such that the copolymer is soluble in water. A composition may comprise an electrolyte and the copolymer. The rheology of an environment comprising an electrolyte may be modified by adding the copolymer to the environment.

Copolymer, composition and method for modifying rheology

In a process for forming a hydrogel, a precursor crosslinkable through disulfide bonds for forming the hydrogel is provided in a solution. The precursor comprises a branched molecular structure, which comprises a plurality of branches. At least three of the branches each comprises a disulfide bond. The pH in the solution is adjusted to initiate thiol-disulfide exchange in the precursor, thus crosslinking the precursor through disulfide bonds formed by thiol-disulfide exchange. After the precursor is sufficiently crosslinked to form a hydrogel, the pH in the solution is adjusted to inhibit further thiol-disulfide exchange in the hydrogel. Further, a hydrogel matrix may comprise a polymer substantially crosslinked through disulfide bonds. The polymer may comprise a hydrophobic poly(amido amine) core and an amino-functionalized hydrophilic shell.

Crosslinking branched molecule through thiol-disulfide exchange to form hydrogel

There is presently provided a stimulus-responsive polymer comprising a biodegradable polymer backbone and a stimulus-responsive pendant group attached to the biodegradable polymer backbone, wherein the biodegradable polymer backbone comprises a poly(amino ester) or a poly(amido amine), the poly(amido amine) optionally comprising a disulfide linkage in the backbone.

Stimulus-responsive biodegradable polymers and methods of preparation

A process for forming a composite film on a substrate comprises providing a suspension comprising an ionised polymer and functionalised carbon nanotubes in a solvent, at least partially immersing the substrate and a counterelectrode in the suspension, and applying a voltage between the substrate and the counterelectrode so as to form the composite film on the substrate. Electrical charges on the polymer and on the nanotubes have the same sign and the voltage is applied such that the charge on the substrate has the opposite sign to the charge on the polymer and the nanotubes.

Composite films comprising carbon nanotubes and polymer

The present invention provides a branched, a dendritic, or a hyperbranched poly(amino ester) having a polymer backbone comprising a plurality of branches, wherein the polymer backbone has at least one secondary and at least one tertiary amine linkage. Branched poly(amino ester)s are prepared via a Michael addition reaction of a tris(acrylate ester)monomer with a diamine monomer. In one aspect, the diamine monomer has a primary amino group and a secondary amino group. The poly(amino ester) compounds can be end-capped by reacting with a suitable agent. The present invention also provides applications including, but are not limited to, the delivery of bioactive agents, such as drugs, DNA or RNA; or biocompatible imaging.

Growing community of inventors

Singapore, Singapore

Decheng Wu