Jutta Christine Wandrey

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The solids are removed from an aq. suspension contg. 0.01-200 g solids/L using a suspension of a water-sol., high-mol. wt., highly crosslinked copolymer of di-Me diallyl ammonium chloride and 0.1-3 mol.% of a crosslinked comonomer, mixed with acryloguanamine copolymers. The crosslinking polymers are ammonium salts with >=2 allyl groups, e.g., Me triallyl ammonium chloride and tetrallyl ammonium chloride. The suspension is used at a rate of 0.005-2%, based on solids content, at 276-333 K and pH 3-9 to form a

With the discovery of important biological roles of carbon monoxide (CO), the use of this gas as a therapeutic agent has attracted attention. However, the medical application of this gas has been hampered by the complexity of the administration method. To ...

A process for prepg. a water sol. polymer comprises: providing a polymn. reaction mixt. comprising one or more polymerizable ethylenically unsatd. monomers; polymg. the ethylenically unsatd. monomers; and adding to the reaction mixt. during polymn. one or more chain branching agents (e.g., methylenebisacrylamide) either continuously or semi-continuously, the semi-continuous addn. further comprising at least two discrete addns. The polymers, typically acrylamide-based, have improved flocculating and dewateri

Poly(vinylbenzylammonium chloride) (PVBAC) polyelectrolytes possessing defined chain lengths, narrow chain length distributions, uniform charge d., but substituents of different hydrophilicity and size at the quaternary ammonium group were used as model compds. to study the influence of the chain length and the substituent type on the interaction with oppositely charged monolayers. Langmuir monolayers were formed from dimyristoylphosphatidic acid (DMPA). Pressure-area and pressure-time isotherms revealed an

The achievement of high ionic conductivity in new "polymeric ionic liquids" (PILs) is of great interest as it refers to the solid state electrolytes and their applications in electrochemistry. Four ionic monomers, including two new ones, namely N-[(2-metha ...

The title aq. polymer contg. pyrrolidinium chloride units is stirred with heating until a water content of

The overall topic of the investigation was the sepn. of basic proteins by cation exchange displacement chromatog. For this purpose two principal column morphologies were compared for the sepn. of RNase A and a-chymotrypsinogen, two proteins found in the bovine pancreas. These were a column packed with porous particles (Macro-Prep S, 10 mm, 1000 .ANG.) and a monolithic column (UNOTM S1). Both columns are strong cation exchangers, carrying -SO3--groups linked to a hydrophilic polymer support. Poly(diallyl-dim

A general description of the electrolytic cond. behavior of highly charged strong polyelectrolytes in dil. and semidilute aq. solns. is presented. For the first time this model considers the effects of the molar mass, charge d. (for charge distances less than the Bjerrum length), polyelectrolyte concn., and the ionic strength adjusted by both the polyelectrolyte concn. (cp in monomol L-1) and added simple salt concn. (cs in mol L-1). Above the overlap concn. (c*) the molar mass influence is weak; below c* t

The free-radical homopolymerization of 1,3-bis(N,N,N-trimethylammonium)-2-propylmethacrylate dichloride (di-M) and 1,3-bis(N,N,N-trimethylammonium)-2-propylacrylate dichloride (di-A) in aqueous solution yields cationic polyelectrolytes (PEL) with theoretic ...

Polyelectrolyte complex membrane formation has been studied, online, using the synthetic boundary technique of an Optima XL-I anal. ultracentrifuge. This recent method, established by the first author, has now been evaluated concerning its sensitivity to monitor differences in the membrane formation if the membrane components and exptl. conditions are varied. For this purpose the membrane formation of sodium alginate with three polycations, poly(vinylamine)hydrochloride, poly(L-lysine)hydrochloride, and chi

Cell microencapsulation and subsequent transplantation of the microencapsulated cells require multidisciplinary approaches. Physical, chemical, biological, engineering, and medical expertise has to be combined. Several natural and synthetic polymeric mater ...

A brief review with 18 refs. is provided of the principal research and development activities of the Lab. of Polyelectrolytes and BioMacromols. at the Swiss Federal Institute of Technol. These include, in particular, the synthesis of tailor-made polyelectrolytes, the development of novel materials based on polyelectrolytes as well as basic research in the field of process technologies for synthesis and structure formation. The applications focus on the environment, biotechnol. and medicine. [on SciFinder (R

An aq. soln. of cationic, high mol. wt. poly(diallyldimethylammonium chloride) (I) [26062-79-3], synthesized in very alk. soln. with a ternary initiation system, is added in amts. of 0.25-4.0 mL/L to accelerate sedimentation of solid particles from coal-contg. wastewaters. Thus, 0.5 mL of a 0.1% aq. soln. of I was mixed thoroughly with 5-10 g/L coal-solids contg. wastewater from a briquet factory to produce macroflocs and completely sep. coal particles and water in 100

Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this ...

Suspended solids are removed from wastewaters and waters contg. 10-4-10 g solids/L using poly(di-Me diallyl ammonium chloride) and a water-sol., highly branched, high mol. copolymer of di-Me dially ammonium chloride and 0.1-3.0 mol% of a crosslinking comonomer, e.g., Me triallyl ammonium chloride, tetraallyl ammonium chloride, triallyl amine hydrochloride, N,N,N',N'-tetraallyl ethylenediamine hydrochloride, or methylene bisacrylamide. The flocculant is used at an amt. of 0.05-2%, based on the solids, and at

Sedimentation of solids is accelerated and complete, resulting in a high-quality effluent, when a 0.1% soln. of equal parts of poly(dimethyl-diallyl-ammonium chloride) cationic flocculant and a nonionic or anionic polyacrylamide is used at a rate of 0.25-4 mL/L wastewater. Thus, briquet manufg. wastewater contg. 5-10 g solids/L was treated with the above mixt. at 0.5 mL/L under turbulent mixing conditions, flocculanted for 15 min and allowed to settle for 30 min, forming a brown coal sludge having >100 g so

In the title process, which improves productivity and wastewater clarity, paper is prepd. from pulp slurries contg. 0.1-1.5% solids and 0.01-0.5% (based on solids) highly-branched, high-mol.-wt. copolymer of diallyldimethylammonium chloride (I) with 0.1-3.0 mol% crosslinking monomers. A slurry of 0.8% fibers (wastepaper) contg. 0.02% I copolymer with 0.1 mol% triallylmethylammonium chloride had dewatering time (250 mL filtrate) 5.1 s and gave a sheet contg. 97.5% solids, vs. 5.7 and 95.2, resp., with I homo

A review on the methods of characterization of multicomponent microcapsules. Requirements to measure the ingress and egress of small and macromols. through the membrane are discussed, along with the relevant theory. The relevant factors to consider in microcapsule design are presented, together with a brief overview of recent techniques for micromech. characterization. The selected methods of the exptl. detn. of mass transport properties, as applied to microcapsules, are summarized. Examples of mass transpo

Suspended org. and inorg. solids are removed from aq. soln. by adding an improved water-sol. acryloguanamine copolymer flocculant with mol. wt. >2000 and contg. 0-1000 units each of acrylamide, vinyl guanamine, acrylic acid, trimerized acrylonitrile structure I, and acrylonitrile groups in an acid aq. soln. at pH > 2 and temp. above the f.p., optionally with inorg. flocculants. Thus, when the copolymeric flocculant was added at 5, 10, 12, 17, 21, 30, and 50 mg/L to a soln. contg. suspended solids 0.05-1.2 g

Aggregation of particles is fundamental for improving the performance of many solid/liquid processes. Aggregation can be induced by different means, and one of the most common is based on the addition of polymeric additives, namely polyelectrolytes. In thi ...

Jutta Christine Wandrey

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Polymeric flocculant for removal of solids from aqueous suspensions or sludges such as sewage sludge

Carbon Monoxide-Releasing Micelles for Immunotherapy

Preparation of water-soluble polymers for flocculants with improved dewatering characteristics

Interactions of highly charged polyelectrolytes with monolayers of oppositely charged amphiphiles

Polymeric Ionic Liquids: Comparison of Polycations and Polyanions

Preparation of water-soluble highly branched cationic polymer powder

Investigation of particle-based and monolithic columns for cation exchange protein displacement chromatography using poly(diallyl-dimethylammonium chloride) as displacer

Concentration regimes in polyelectrolyte solutions

Effect of Very High Charge Density and Monomer Constitution on the Synthesis and Properties of Cationic Polyelectrolytes

Study of polyelectrolyte complex formation applying the synthetic boundary technique of analytical ultracentrifugation

Contribution of polymeric materials to progress in xenotransplantation of microencapsulated cells - A review

Polyelectrolytes: Research, development, and applications

Flocculant for promoting solid sedimentation from coal-containing wastewaters

A Multilaboratory Comparison of Calibration Accuracy and the Performance of External References in Analytical Ultracentrifugation

Copolymeric flocculant for removal of suspended solids from sewage, industrial wastewaters, and water

Polyelectrolytic flocculant for accelerating solid sedimentation from coal-containing wastewater

Process for solids retention and accelerated dewatering in paper manufacture

Characterization of microcapsules

Removing solids suspended in an aqueous medium

An experimental design methodology to evaluate the importance of different parameters on flocculation by polyelectrolytes