摘要:
A method for purifying a polyethylene glycol compound having one amino group, which includes (A) preparing an aqueous solution of the compound having a pH of 1 to 5, (B) an extracting step of mixing the aqueous solution with a mixed organic solvent to cause layer separation into organic and aqueous layers, wherein a ratio of an organic solvent I is 25 to 65% by mass and a ratio of an organic solvent II is 75 to 35% by mass, the organic solvent I is selected from an aromatic hydrocarbon and an ester, the organic solvent II is a halogenated hydrocarbon, and a mixing ratio Y of I to II, temperature T (° C.) at mixing, and molecular weight M of the compound satisfy the following relationship: 1.9×10−6M+0.09≦Y−0.015T≦−1.4×10−6M+0.44 and (C) recovering the compound from the aqueous layer.
摘要:
The invention relates to a batch chromatography process the purification of (per)fluoropolyether (PFPE) carboxylates, in particular to a process for increasing the average functionality of PFPE carboxylates mixtures.
摘要:
Provided herein are long circulating material free (LCMF) poloxamer compositions and uses thereof. In particular, provided are LCMF poloxamer 188 compositions and uses thereof. Also provided are supercritical fluid extraction (SFE) methods and high pressure (subcritical) methods for preparing poloxamer compositions, particularly the LCMF poloxamer compositions.
摘要:
The present invention relates to a process for preparing polyether polyols by base-catalyzed addition of alkylene oxides (epoxides) onto starter compounds which are solid at room temperature and have Zerevitinov-active hydrogen atoms, a particular feature of which is that visually clear and/or homogeneous products are obtained even in the absence of solvents.
摘要:
Intermediate products (compounds, semi-finished goods) for polymer materials having coupled components, to the polymer materials based on the intermediate products, and to the components to be manufactured therefrom. A method for producing intermediate products, polymer materials and components, and to the use thereof.
摘要:
Disclosed are a method for purifying poloxamers, comprising dissolving poloxamers in an organic solvent to prepare a polymer solution, and removing organometals or water from the polymer solution by at least one physical method selected from mixing of activated carbon with the polymer solution and centrifugation of the polymer solution, and poloxamers purified by the method.
摘要:
A process for purification of water soluble polymers is provided. A polymer of interest can be separated from a mixture of polymers, provided the polymer of interest differs from other polymers in the mixture in the number of reactive terminal groups. The process involves derivatizing polymers at the reactive terminal groups with a derivatizing molecule, bearing either (i) two or three cationic or anionic ionizable groups, and a group capable of covalent bonding to the reactive terminal groups or (ii) three or four ionizable groups, at least one of which is capable of covalent bonding to the reactive terminal groups; followed by ion exchange. The process allows removal of PEG from MPEG, and can be used for polymers having an average size greater than 9,000 Da Derivatization may be reversible in order to allow re-use of recovered contaminant polymers.
摘要:
The present invention relates to polyetherols are prepared by a process comprising the reaction of at least one alkylene oxide with at least one initiator compound in the presence of at least one double metal cyanide compound to give a polyetherol and the treatment of the resulting polyetherol with steam or with an inert gas and steam, and the polyetherols obtainable by such a process as well as the use thereof for the synthesis of polyurethanes.
摘要:
The present invention comprises novel preparations of polyoxypropylene/polyoxyethylene octablock copolymers which retain the growth-promoting and immunity-enhancing activity of commercially-available preparations, but are free from the undesirable effects which are inherent in the prior art preparations. Because the polyoxypropylene/polyoxyethylene copolymers which comprise the present invention have a more homogenous population of molecules with fewer low molecular weight species than prior art preparations, the biological activity of the copolymer is better defined and more predictable. Moreover, the polyoxypropylene/polyoxyethylene copolymer of the present invention substantially reduces any risk to human health through the consumption of food animals since the copolymer hereof is not absorbed into the animal's edible tissue. Methods for preparation of the polyoxypropylene/polyoxyethylene copolymer of the present invention are also provided.
摘要:
Use in optical systems as liquids to transmit light at wave lengths lower than 250 nm, in particular at 157 nm, of perfluoropolyethers having the following formula: X1—O(CF2O)n(CF2CF2O)m(CF2CF2CF2O)p (CF2CF2CF2CF2O)q—X2 (I) wherein: the repeating units —CF2O—, —CF2CF2O—, —CF2CF2CF2O—, —CF2CF2CF2CF2O— are statistically distributed along the chain; —X1 and —X2 are perfluoroalkyl chain end groups equal to or different from each other, having formula —(CF2)zCF3 wherein z is 0 or an integer from 1 to 3; n, m, p, q are 0 or integers comprised between 1 and 100, with the proviso that: at least one among n, m, p and q is different from zero; the ratio between the oxygen atoms and the carbon atoms (O/C) is higher than 0.33; wherein the chlorine atoms, determined by 19F-NMR are substantially absent.