##STR00001##

The present application discloses films comprising regioselectively substituted cellulose esters and a component A wherein rings A, B, C, R.sup.1, R.sup.2, R.sup.5, R.sup.6, R.sup.8, m, n, and k are defined herein. The films are C+ films that exhibit improved wavelength dispersion. <

The present disclosure belongs to the technical field of hemostatic materials, and specifically relates to a degradable hemostatic sponge and a preparation method and use thereof, and a degradable drug-loaded hemostatic sponge. The degradable hemostatic sponge provided by the present disclosure is prepared from raw materials including a crosslinking-modified starch and a cellulose through freeze-drying, where a mass ratio of the crosslinking-modified starch to the cellulose is (0.2-5):1. The degradable hemostatic sponge provided by the present disclosure has a high water-absorbing rate and a large water-absorbing capacity, shows a high support strength and a long support time after water absorption, and is made from plant-derived raw materials and thus may be completely biodegraded. The degradable drug-loaded starch hemostatic sponge provided by the present disclosure has a drug-loaded coating attached to a surface of the sponge, where the drug is slowly released while a support is maintained.

The present disclosure relates to a method and a composition comprising an esterase for enzymatic surface modification of a polyester. The present disclosure also relates to a method of degradation or hydrolysis of an insoluble plant material.

Provided is a polymer material containing at least one kind of a cellulose derivative having (a) an organosilyl group (the organosilyl group having a first aliphatic group, an unsaturated aliphatic group, or an aromatic group), and (b) an acyl group or a second aliphatic group.

Provided is a composition for hot melt extrusion including a drug and hypromellose acetate succinate (HPMCAS) having a hydroxypropoxy molar substitution of 0.40 or more and a mole ratio of an acetyl group to a succinyl group of less than 1.6. Further, provided is a method for producing a hot melt extrudate including the step of hot melt-extruding a composition for hot melt extrusion including a drug and hypromellose acetate succinate having a molar hydroxypropoxy substitution of 0.40 or more and a mole ratio of an acetyl group to a succinyl group of less than 1.6, at a hot melt temperature of not lower than a melting temperature of the hypromellose acetate succinate or of not lower than a temperature at which both the hypromellose acetate succinate and the drug are melted.

Provided is a polymer material containing at least one kind of a cellulose derivative having (a) an organosilyl group (the organosilyl group having a first aliphatic group, an unsaturated aliphatic group, or an aromatic group), and (b) an acyl group or a second aliphatic group.

In a water-redispersible polymer powderthe polymer is at least one esterified cellulose ether comprising (i) groups of the formula C(O)RCOOA or (ii) a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA, wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, andthe polymer powder comprises from 0.05 to 20 percent of at least one salt of a fatty acid, based on the weight of the esterified cellulose ether(s).

A process for producing an aqueous composition comprising a dispersed esterified cellulose ether comprises the steps of grinding, in the presence of an aqueous diluent an esterified cellulose ether comprising (i) groups of the formula C(O)RCOOA or (ii) a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA, wherein R is a N divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, blending a salt of a fatty acid with the esterified cellulose ether and choosing the amounts of aqueous diluent, esterified cellulose ether and salt of a fatty acid that the produced aqueous composition comprises at least 20 percent of the dispersed esterified cellulose ether and heating the aqueous composition to a temperature of from 37 to 80 C during or after the grinding step.

Provided are a composition for hot-melt extrusion which can be hot-melt extruded at a temperature lower than a conventional temperature and therefore free of heat-induced deactivation of a drug; and a method for producing a hot-melt extrusion product which is simpler than a spray-drying method. More specifically, provided is a composition for hot-melt extrusion including a drug and hypromellose acetate succinate (HPMCAS) having a hydroxypropoxy molar substitution of 0.40 or more. Also provided is a method for producing a hot-melt extrusion product including a step of hot-melt extruding a composition for hot-melt extrusion including a drug and hypromellose acetate succinate having a hydroxypropoxy molar substitution of 0.40 or more at a hot-melt temperature of melting temperature of the hypromellose acetate succinate or higher, or at a hot-melt temperature equal to or higher than a temperature at which both the hypromellose acetate succinate and the drug become melted.

##STR00001## The present application discloses films comprising regioselectively substituted cellulose esters and a component A wherein rings A, B, C, R.sup.1, R.sup.2, R.sup.5, R.sup.6, R.sup.8, m, n, and k are defined herein. The films are C+ films that exhibit improved wavelength dispersion. <