Patent · US Active

Esterified cellulose ethers of high molecular weight and homogeneity

US10759873B2 · kind B2 · utility

0Cited by

2References

17Claims

0Family size

Assignee

DOW GLOBAL TECHNOLOGIES LLC · US

Inventors

Oliver Petermann · Hamburg, DE
Matthias Sprehe · Walsrode, DE
Meinolf Brackhagen · Walsrode, DE

Key dates

Filing date	Jan 27, 2015
Grant date	Sep 1, 2020
Priority date	—
Expiry date	Oct 30, 2036

Classification

Technology area (CPC A)Human Necessities
CPC primaryA61K9/2866
WIPO fieldPharmaceuticals
WIPO sectorChemistry

Abstract

Esterified cellulose ethers which have i) as ester groups aliphatic monovalent acyl groups or a combination of aliphatic monovalent acyl groups and groups of the formula —C(O)—R—COOA wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, ii) a weight average molecular weight Mw of from 80,000 Dalton to 220,000 Dalton, iii) a Polydispersity Mw/Mn of from 1.3 to 4.0, and iv) an Mz/Mn of not more than 18.5, when the weight average molecular weight Mw, the number average molecular weight Mn and the z-average molecular weight Mz are measured by SEC-MALLS using as mobile phase a mixture produced from 40 parts by volume of acetonitrile and 60 parts by volume of aqueous buffer containing 50 mM NaH2—PO4 and 0.1 M NaNO3. are useful as enteric polymers for pharmaceutical dosage forms.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.