Determination of solvent/polymer interaction parameters of moderately concentrated polymer solutions by vapor pressure osmometry

Karimi, Mohammad; Albrecht, Wolfgang; Heuchel, Matthias; Weigel, Th.; Lendlein, Andreas

doi:10.1016/j.polymer.2008.03.036

Cited by 28 publications

(13 citation statements)

References 33 publications

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“…PEI (Ultem 1000, General Electric, USA) has a molecular weight of M w = 30,000 ± 10,000 g/mol, M n = 12,000 ± 4,000 g/mol given by the datasheet and a M w ≈ 32,800 g/mol, M n ≈ 18,000 g/mol published elsewhere [22].…”

Section: Polymer Preparationmentioning

confidence: 99%

Interaction of thrombocytes with poly(ether imide): The influence of processing

Braune¹,

Lange²,

Richau³

et al. 2010

Clinical Hemorheology and Microcirculation

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The processing of polymers for blood contacting devices can have a major influence on surface properties. In this study, we fabricated poly(ether imide) (PEI) membranes and films to investigate the effects of the processing on physicochemical surface properties by atomic force microscopy (AFM), scanning electron microscopy, contact angle as well as zeta potential measurements. A static platelet adhesion test was performed to analyze the thrombogenicity of both devices. While contact angle measurements showed similar levels of hydrophobicity and zeta potential values were equivalent, mean surface roughness as well as surface energies in the dispersive part were found to be increased for the PEI membrane. The static platelet adhesion test showed a significantly decreased number of adherent platelets per surface area on the PEI film (178.98 ± 102.70/45000 m 2 ) compared to the PEI membrane (504 ± 314.27/45000 m 2 ) and, consequently, revealed evidence for higher thrombogenicity of the PEI membrane. This study shows that processing can have a significant effect on platelet adhesion to biomaterials, even though, molar weight was identical. Thrombogenicity of polymer-based cardiovascular devices, therefore, have to be evaluated at the final product level, following the entire processing procedure.A wide range of polymers like polyurethanes, silicones or PEG-based copolymers have received growing attention for biomedical applications due to their better hemocompatibility and processing features compared to metals [26], whereupon the ideal hemocompatible surface inhibits any platelet adhesion [20]. Several parameters seem to influence hemocompatibility. Chapman et al. concluded that hydrophilic, noncharged surfaces, without hydrogen-donors are more resistant to protein adsorption and are able to prevent platelet adherence [13]. In addition the processing itself can lead to changes e.g. in surface roughness which can influence platelet adhesion as well [16,17,31,33,42].In the present study the influence of different processing of poly(ether imide) (PEI, Ultem 1000 ® , General Electric, USA) on the interaction of blood platelets with poly(ether imide) (PEI) was analyzed. PEI is non-toxic, sterilizable [1], processable to different formed-bodies [4,5], and enables a wide range of surface modifications by straightforward wet chemistry [2, 3] and was already evaluated as a biomaterial [6,24,32,35,36] suitable for applications in regenerative medicine [30,41].Since platelet interactions are controlled by physical and chemical characteristics [26], including their possible distribution in submicroscopical domains and surface roughness [37], characteristic surface parameters were analyzed. To reveal the influences of processing on surface properties, membranes and films from PEI were fabricated and the effects on the physicochemical properties and thrombogenicity investigated. Material and methods Polymer preparationAll processed devices were fabricated from the same charge of the polymer. PEI (Ultem 1000, General Electric, USA)...

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Section: Polymer Preparationmentioning

confidence: 99%

Interaction of thrombocytes with poly(ether imide): The influence of processing

Braune¹,

Lange²,

Richau³

et al. 2010

Clinical Hemorheology and Microcirculation

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“…In some cases, increasing the relative humidity up to 90% results in the formation of membranes with larger surface pore size and regular distribution, whereas in many others, it acts vice versa . Generally, the main effect of nonsolvent vapor content is on kinetic behavior of the ternary system during the membrane formation because the amount of relative humidity influences the rate of mass transfer of nonsolvent on the cast film …”

Section: Introductionmentioning

confidence: 99%

“…About the importance of controlling effective preparation parameters as well as modification technique, making a reliable model to study fabrication procedure for reaching high performance in microfiltration is a useful tool not only to predict fabrication parameters but also to optimize conditions for developing better performing membrane . Recently, genetic programming (GP) as a branch of genetic algorithm (GA) has been successfully applied in the field of membrane technology . Tan et al represented a hybrid model by using GA to optimize the fabrication of polyetherimide ultrafiltration membrane via dry/wet phase inversion.…”

Section: Introductionmentioning

confidence: 99%

Experimental investigation and mathematical modeling of nano‐composite membrane fabrication process: Focus on the role of solvent type

Ghandashtani

Tavangar

Ashtiani

et al. 2018

Asia-Pacific J Chem Eng

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In this study, the effect of fabrication parameters on the performance of nano-SiO 2 -embedded membranes fabricated by three prevalent solvents was investigated. Genetic programming was applied for modeling and estimating the best preparation conditions to obtain a proper membrane for oily wastewater microfiltration. Membranes were prepared via a combination of vapor-induced phase separation and nonsolvent-induced phase separation methods. Different types of solvents such as N-methyl-2-pyrrolidone, N,N-dimethyl formamide, and dimethyl sulfoxide were used in cooperating with SiO 2 nanoparticles to improve hydrophilicity properties of polyethersulfone. Thermodynamic behavior of solvents and their interaction with polymer and nonsolvent were considered as criteria for forming a suitable membrane with the maximum effectiveness of nanoparticles. The results showed that nanoparticles are more influential along with a solvent that has a weak affinity with a polymer, which subsequently can produce efficient membranes under conditions with a balance between exposure time and relative humidity. The optimum amounts of parameters were estimated by genetic algorithm to introduce a condition for having a membrane with the maximum permeate flux. Membranes fabricated with dimethyl sulfoxide represented the highest pore size and the most hydrophilic surface, which, in turn, led to the desired membrane (permeate flux 300 L/m 2 hr and oil rejection 97%).

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“…has increased the interest and therewith research in the field of polymers [1][2][3][4]. Generally, in most of applications of polymers we are often dealing with polymer solutions [5][6][7].…”

Section: Introductionmentioning

confidence: 99%