The invention is directed to biomedical polyurethanes. The invention is particularly directed to biomedical polyurethanes with improved biodegradability and to an improved preparation of the biomedical polyurethanes. In particular the present invention provides a biomedical polyurethane having the formula (A-B-C-B).sub.n, wherein A denotes a polyol, B denotes a diisocyanate moiety, C denotes a diol component and n denotes the number of recurring units, and wherein the B-C-B segment is bioresorbable.

Provided is a method for forming a multilayer coating film, the method being capable of forming a multilayer coating film having excellent chipping resistance, adhesion, and finished appearance. The method for forming a coating film uses a 3-coat and 1-bake system in which a three-layered multilayer coating film obtained by sequentially applying a first coloring paint (X), a second coloring paint (Y), and a clear coating paint (Z) onto an object to be coated is heated and cured at the same time, wherein the first coloring paint (X) and the second coloring paint (Y) contain a hydroxyl group-containing resin, and the clear coating paint (Z) contains a hydroxyl group-containing acrylic resin (a) and an aliphatic triisocyanate compound (b1) having a molecular weight within a specific range.

The present invention relates novel furan based amine cross-linkers with improved thermomechanical and water barrier properties. The novelty of this invention is the use of aromatic, and hydrophobic aliphatic aldehydes to bridge two furfuryl amines, which yields a diamine or tetra amines with a significantly enhanced hydrophobic character. These diamine cross-linkers exhibit enhanced water barrier properties and thermomechanical properties when cured with both commercial and synthetic epoxies.

The present invention provides bio-based aromatic diisocyanate of formula (I). [Formula should be inserted here] wherein X is OCH.sub.3, Y is selected from —H or OCH.sub.3, and m=0-12. The present invention further provides a method for preparation of aromatic diisocyanate of formula (I) useful for preparation of polyurethane.

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The invention features oligofluorinated cross-linked polymers and their use in the manufacture of articles and coating surfaces.

Biobased diisocyanates are derived from 3-petadecyl phenol, which is derived from Cardanol harvested from cashew nutshell liquid food waste. The biobased diisocyanates are of the formulas:

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wherein R is an alkyl chain C.sub.15H.sub.31 (n-pentadecyl); R.sub.1═CH.sub.3 or COCH.sub.3; and R.sub.2 is an alkylene of from about 1 to 18 carbon atoms.

A method for preparing a biomass-based conductive hydrogel by 3D printing is provided. Firstly, a cellulose-based macromonomer, a rosin-based monomer, an acrylic acid monomer and an initiator are mixed in a certain proportion, stirred, and dissolved at 25-70° C. Then, diisocyanate in an amount of 5-10 wt % of a total mass of the monomers is added to the mixed solution and mixed uniformly to prepare a 3D printing photosensitive resin solution. An SLA light-curing 3D printer is used to print a hydrogel precursor 1 with a complex shape. Next, the hydrogel precursor 1 is heated to obtain a hydrogel precursor 2 with a dual-curing network. Finally, the obtained hydrogel precursor 2 is swelled in a 1-15 wt % alkaline solution at 5-60° C. for 0.1-10 hours to obtain the biomass-based conductive hydrogel.

Bioactive liquid formulations are formed of combinations of absorbable, segmented aliphatic polyurethane compositions and liquid polyether for use as vehicles for the controlled release of at least one active agent for the conventional and unconventional treatment of different forms of cancer and the management of at least one type of bacterial, fungal, and viral infection.

Biological-based polyurethanes and methods of making the same. The polyurethanes are formed by reacting a biodegradable polyisocyanate (such as lysine diisocyanate) with an optionally hydroxylated biomolecule to form polyurethane. The polymers formed may be combined with ceramic and/or bone particles to form a composite, which may be used as an osteoimplant.

The invention provides novel flame-retardant polymers and materials, their synthesis and use. More particularly, the flame-retardant polymers are deoxybenzoin-derived polymers.