A method for operation in wellbore, the method comprises: pumping a fluid barrier into a wellbore through a tubular, the fluid barrier being operable to separate a cement slurry from a second fluid; the fluid barrier comprising a polyurethane member derived from a polyurethane forming composition comprising a para-phenylene diisocyanate terminated polycarbonate prepolymer and an aromatic diol.

The polymer comprises units of formula (I) and of formula (Ibis), being comprised the molar ratio between units (I) and (Ibis) comprised from 1.0:0.2 to 1.0:0.8, and wherein R.sub.4 are independently selected from radicals of formula (II), (III), and (IV), R.sub.1 and R.sub.1′ are independently selected from: —H, (C.sub.1-C.sub.20)alkyl, (C.sub.5-C.sub.14)aryl, —OR.sub.5, —(CO)R.sub.6, —O(CO)R.sub.7, —(SO)R.sub.8, —NH—CO—R.sub.9, —COOR.sub.10, —NR.sub.11R.sub.12, —NO.sub.2, and halogen; R.sub.2, R.sub.2′, R.sub.3, and R.sub.3′ are —H; P is a polymeric chain, R.sub.5 to R.sub.12 are independently selected: —H, (C.sub.1-C.sub.20)alkyl, and (C.sub.5-C.sub.14)aryl;R.sub.13 and R.sub.14 are independently selected from (C.sub.1-C.sub.5)alkyl, and (C.sub.5-C.sub.14)aryl;, m is from 3 to 4; n is from 1 to 2; and p is from 1 to 2 provided that n+m+p sums 6; the polymer comprising from 5 to 25 weight % of urea moieties, and having H-bonding and pi-pi staking interactions between the urea groups, and a tensile strength comprised from 3 to 15 MPa.

The polymer comprises units of formula (I) and of formula (Ibis), being comprised the molar ratio between units (I) and (Ibis) comprised from 1.0:0.2 to 1.0:0.8, and wherein R.sub.4 are independently selected from radicals of formula (II), (III), and (IV), R.sub.1 and R.sub.1′ are independently selected from: —H, (C.sub.1-C.sub.20)alkyl, (C.sub.5-C.sub.14)aryl, —OR.sub.5, —(CO)R.sub.6, —O(CO)R.sub.7, —(SO)R.sub.8, —NH—CO—R.sub.9, —COOR.sub.10, —NR.sub.11R.sub.12, —NO.sub.2, and halogen; R.sub.2, R.sub.2′, R.sub.3, and R.sub.3′ are —H; P is a polymeric chain, R.sub.5 to R.sub.12 are independently selected: —H, (C.sub.1-C.sub.20)alkyl, and (C.sub.5-C.sub.14)aryl;R.sub.13 and R.sub.14 are independently selected from (C.sub.1-C.sub.5)alkyl, and (C.sub.5-C.sub.14)aryl;, m is from 3 to 4; n is from 1 to 2; and p is from 1 to 2 provided that n+m+p sums 6; the polymer comprising from 5 to 25 weight % of urea moieties, and having H-bonding and pi-pi staking interactions between the urea groups, and a tensile strength comprised from 3 to 15 MPa.

The present inventions concerns compositions for producing thermoset polyurethanes, comprising polyisocyanates and polyols selected from a list consisting of allieyclic, aromatic compounds and branched polyesters. The films obtained from these compositions exhibit a high transparency, high thermal stability and good chemical resistance, and a method to produce the same. The said polyurethane films can be widely used in electronics industry where high transparency, high thermal resistance and good chemical resistance are the main requirements. Particularly, these films can be used as the substrates for conductive coatings and barrier coatings. These functionally coated films are particularly useful in applications such as touch panels or photo-voltaic cells.

Porous three-dimensional networks of polyimide and porous three-dimensional networks of carbon and methods of their manufacture are described. For example, polyimide aerogels are prepared by mixing a dianhydride and a diisocyanate in a solvent comprising a pyrrolidone and acetonitrile at room temperature to form a sol-gel material and supercritically drying the sol-gel material to form the polyimide aerogel. Porous three-dimensional polyimide networks, such as polyimide aerogels, may also exhibit a fibrous morphology. Having a porous three-dimensional polyimide network undergo an additional step of pyrolysis may result in the three dimensional network being converted to a purely carbon skeleton, yielding a porous three-dimensional carbon network. The carbon network, having been derived from a fibrous polyimide network, may also exhibit a fibrous morphology.

To provide a polymer material having properties that allow the polymer material to replace a polyimide and a polyamide synthesized from a petroleum raw material, said polymer material being synthesized from a raw material derived from natural molecules. [Solution] This polymer material is obtained by polymerizing a polymer raw material comprising a dimer of 4-amino cinnamic acid or a dimer of a 4-amino cinnamic acid derivative, which are natural molecules, wherein the carboxyl group is protected by an alkyl chain. The TGA curve of a polyamide acid (PAA-1) and a polyimide (PI-1) according to the present invention is shown in FIG. 5.

The present invention relates to multi-component compositions including an isocyanate component and an amine component, wherein the isocyanate component includes a prepolymer, obtainable from toluene isocyanate and a polytetramethylene polyol, and the amine component includes a dialkylthio aryl diamine and possibly a polytetramethylene oxide polyamine. Corresponding compositions can be advantageously used as flowable or spreadable resin systems for producing surface protection coatings in casting house applications and are characterized by a significantly improved resistance to abrasion in comparison with conventional casting resin systems based on hexamethylene diisocyanate and dimethyl thiotoluene diamine.

A self-healing coating composition for use on metals includes a polyurea, an epoxy ester unsaturated resin, a combination of amine terminated siloxane and epoxy terminated siloxane and an organoclay. The polyurea is a water-soluble, aromatic polyurea and likewise, the epoxy ester is a water-soluble, aromatic epoxy ester. The coating composition is formed in a non-volatile solvent, such as N-Methylpyrrolidone. It can be applied to a metal surface and cured at room temperature to form a coating that is resistant to corrosion. Further the coating self-heals in a manner similar to a chromate coating.

The present invention relates to a process for preparing a porous material, at least comprising the steps of providing a mixture (I) comprising a composition (A) comprising components suitable to form an organic gel and a solvent (B), reacting the components in the composition (A) in the presence of the solvent (B) to form a gel, and drying of the gel obtained in step b), wherein the composition (A) comprises at least one compound (af) comprising phosphorous and at least one functional group which is reactive towards isocyanates. The invention further relates to the porous materials which can be obtained in this way and the use of the porous materials as thermal insulation material and in vacuum insulation panels, in particular in interior or exterior thermal insulation systems as well as in water tank or ice maker insulation systems.

A process comprising a) mixing i) an isocyanate reactive component that contains from 2 to 100 weight percent of an aminobenzoate terminated composition wherein the isocyanate reactive component does not contain a solvent; and ii) an isocyanate terminated component having an isocyanate functionality of from 2 to 6 wherein the isocyanate terminated component does not contain a solvent; at a stoichiometric ratio of NCO to reactive hydrogen in the range of from 0.9 to 2.5; to form an adhesive composition; b) applying the adhesive composition to a primary substrate; and c) laminating the primary substrate with a secondary film to form a laminate structure, is disclosed. The laminate structure can be used as a laminating adhesive.