A biodegradable polymer usable in fishing gear and that biodegrades in aquatic environments. The polymer includes a polymer backbone that has monomeric units that are susceptible to hydrolytic degradation, and a plurality of pH responsive moieties. Each pH responsive moiety is grafted to a respective one of the monomeric units. The pH responsive moieties are relatively hydrophilic when exposed to an aqueous solution of a pro-biodegradation pH range to facilitate hydrolytic degradation of the monomeric units, and are relatively hydrophobic when removed from the aqueous solution of the pro-biodegradation pH range, to protect the monomeric units from hydrolytic degradation.

The biodegradable resin composition according to the present invention contains an aliphatic polyester biodegradable resin and fibrous basic magnesium sulfate.

The biodegradable resin composition according to the present invention contains an aliphatic polyester biodegradable resin and fibrous basic magnesium sulfate.

A heat-shrinkable polyester film includes at least one polyester material made of at least one polyester forming composition which includes a dibasic carboxylic mixture and a diol mixture. The heat-shrinkable polyester film has a heat shrinkage rate of not lower than 25% in a shrinkage direction, which is measured by immersing the heat-shrinkable polyester film in hot water at 65° C. for 10 seconds. A method for producing the heat-shrinkable polyester film is also disclosed.

A heat-shrinkable polyester film includes at least one polyester material made of at least one polyester forming composition which includes a dibasic carboxylic mixture and a diol mixture. The heat-shrinkable polyester film has a heat shrinkage rate of not lower than 25% in a shrinkage direction, which is measured by immersing the heat-shrinkable polyester film in hot water at 65° C. for 10 seconds. A method for producing the heat-shrinkable polyester film is also disclosed.

Disclosed herein, inter alia, are fatty acid and polymer compositions and methods of making the same.

Disclosed herein, inter alia, are fatty acid and polymer compositions and methods of making the same.

A method of extracting underground resources including a step of mixing hydrolysable particles and a proppant to an aqueous dispersion fluid, and introducing the fluid with pressure into an ore chute formed under the ground, wherein as the hydrolysable particles, use is made of spherical particles that include a hydrolysable resin of a weight average molecular weight (Mw) of not less than 5,000 and, specifically, not less than 10,000, and that have an average particle size (D.sub.50) in a range of 300 to 1,000 μm, and a circularity of a short diameter/long diameter ratio of not less than 0.8. The spherical particles have a hyrolysable capability, a circularity and a particle size adapted to the hydraulic fracturing.

A method of extracting underground resources including a step of mixing hydrolysable particles and a proppant to an aqueous dispersion fluid, and introducing the fluid with pressure into an ore chute formed under the ground, wherein as the hydrolysable particles, use is made of spherical particles that include a hydrolysable resin of a weight average molecular weight (Mw) of not less than 5,000 and, specifically, not less than 10,000, and that have an average particle size (D.sub.50) in a range of 300 to 1,000 μm, and a circularity of a short diameter/long diameter ratio of not less than 0.8. The spherical particles have a hyrolysable capability, a circularity and a particle size adapted to the hydraulic fracturing.

A biodegradable aliphatic-aromatic polyester for the production of packaging films, having a Poisson's ratio (RVE) between 800 and 1700, comprising units of at least one dicarboxylic acid and at least one diol, in which Mn≥40000 and Mw/q≤90000, in which q is the percentage by weight of polyester oligomers having a molecular weight≤10000.