The present disclosure provides a crystalline polythiocarbonate and a preparation method thereof. The crystalline polythiocarbonate is a random copolymer and includes five structural units L1 to L5 as shown in the following formula. The method includes carrying out a polymerization reaction natively or in solution using carbon disulfide, ethylene oxide, selectively added third monomer, initiator, Lewis acid, selectively added chain transfer agent, and selectively added solvent as raw materials. This method provides a new way for high value-added application of carbon disulfide and ethylene oxide by using inexpensive carbon disulfide and ethylene oxide as monomers; the product is a random copolymerized crystalline polythiocarbonate with novel structure, which has various chain link structures and excellent mechanical properties, processing properties and degradability.

A terminal-modified polyamide 4 having improved thermal stability is provided. The terminal-modified polyamide 4 consists of a polyamide 4-derived site (A) and a polyalkylenimine-derived site (B), and has a structure in which a polyalkylenimine is amide-bonded to a polymerization terminal of polyamide 4. The weight ratio between the polyamide 4-derived site (A) and the polyalkylenimine-derived site (B) is 100:0.01-100:20. The polyamide 4-derived site (A) is a site derived from polyamide 4 having a number average molecular weight (Mn) of 1,000 to 2,000,000, and the polyalkylenimine-derived site (B) is a site derived from a polyalkylenimine having a number average molecular weight (Mn) of 400 to 100,000.

Disclosed are a degradable resin composition including a cyanate ester (A) and a compound (B) having a hydroxyl group with a hydroxyl group equivalent of less than 240 g/eq., and a degradable cured product and a downhole tool for drilling using the same.

The present disclosure relates to a composition that includes a structure that includes

##STR00001##

where R.sub.1 includes at least one of a carbon atom and/or an oxygen atom, R.sup.2 includes at least one of a carbon atom and/or an oxygen atom, and represents a covalent bond. In some embodiments of the present disclosure, the composition may be bioderived.

A biodegradable foam which includes a poly-ester-based polyurethane foam and a mixture comprised of a soil-dwelling carbon-digesting bacteria embedded in a carrier compound. The mixture of the soil-dwelling carbon-digesting bacteria is homogenously dispersed throughout the polyester-based polyurethane foam. This biodegradable foam exhibits biodegradation rates higher than a polyester-based polyurethane foam absent the soil-dwelling carbon-digesting bacteria.

Microcapsules encapsulating oily core materials have a shell material of hybrid polyurea and poly(beta-amino esters) (PU/PBAE). The microcapsules may have a single shell of hybrid PU/PBAE, dual shells including hybrid PU/PBAE in an inner shell and PBAE in an outer shell crosslinked and deposited to the inner shell, or multiple shells including PU in an inner shell, hybrid PU/PBAE in a transitioning shell, and PBAE in an outer shell. Formation of the microcapsules includes polymerization between multifunctional amine and multifunctional acrylate to produce a water soluble PBAE; polymerization between polyisocyanate in oil phase and multifunctional amine in aqueous solution to produce PU microcapsule, polymerization between polyisocyanate and the amine moiety of PBAE prepolymer to produce hybrid PU/PBAE microcapsule wall; and polymerization between multifunctional acrylate and primary or secondary amine moiety of the PBAE prepolymer to form a PBAE outer shell.

The present invention relates to a novolac-type phenolic resin synthesis process in which there is the addition of lignin, to a novolac-type phenolic resin comprising lignin, and to the use of said phenolic resin.

A method for producing a biodegradable polymer complex and the biodegradable polymer complex are provided. The method comprises preparing a monomer mixture containing adipic acid and terephthalic acid; mixing an organic filler, 1,4-butanediol and a catalyst to prepare a catalyst mixture; and mixing the monomer mixture and the catalyst mixture and performing an esterification reaction. The method provides the biodegradable polymer complex having improved biodegradability with high efficiency and low cost, and excellent mechanical properties.

A black polyester film and a method for manufacturing the same are provided. The black polyester film includes a physically recycled polyester resin and a chemically recycled polyester resin. The physically recycled polyester resin is formed by a plurality of physically recycled polyester chips.

The chemically recycled polyester resin is formed by a plurality of chemically recycled polyester chips and mixed with the physically recycled polyester resin. The plurality of chemically recycled polyester chips further include chemically recycled electrostatic pinning polyester chips. The chemically recycled electrostatic pinning polyester chips contain electrostatic pinning additives, and the electrostatic pinning additives are metal salts. Expressed in percent by weight based on a total weight of the polyester film, a content of the electrostatic pinning additives in the polyester film is between 0.005% and 0.1% by weight. The black polyester film further includes a black additive.

The invention relates, generally, to porous absorbent materials which are suitable for packing antrums or other cavities of the human or animal body. More particularly, it relates to hydrophilic biodegradable foams, which may be used e.g. in the form of a plug or tampon, for instance for controlling bleeding, wound closure, prevent tissue adhesion and/or support tissue regeneration. The invention provides an absorbent foam, suitable for packing antrums or other cavities of the human or animal body, comprising a biodegradable synthetic polymer, which polymer preferably comprises —C(O)—O— groups in the backbone of the polymer, for instance polyurethane and/or polyester units combined with polyethers.