Journal ArticleDOI
Anomalous penetrant transport in glassy polymers V. Cyclohexane transport in polystyrene
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TLDR
In this paper, the authors investigated the transport of liquid cyclohexane through well characterized, initially glassy, crosslinked polystyrene slabs, produced by bulk polymerization of styrene and divinyl benzene using benzoyl peroxide as an initiator at 90°C for 48 h.Abstract:
Transport of liquid cyclohexane through well characterized, initially glassy, crosslinked polystyrene slabs was investigated. The samples were produced by bulk polymerization of styrene and divinyl benzene using benzoyl peroxide as an initiator at 90°C for 48 h; they had initial crosslinking ratios, X, between 0.005 and 0.025 mol DVB/mol styrene, initial thickness of 0.25 mm to 1.80 mm, and the aspect ratio was maintained above 10 to achieve one-dimensional transport. The results of cyclohexane uptake as a function of time were used to elucidate the effects of degree of crosslinking and sample geometry on the mechanisms of penetrant transport. These results were interpreted in terms of relaxational and diffusional mechanisms.read more
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Drug release modulation by physical restrictions of matrix swelling
Paolo Colombo,U. Conte,Andrea Gazzaniga,Loretta Maggi,Maria Edvige Sangalli,Nicholas A. Peppas,A. La Manna +6 more
TL;DR: In this article, the authors present the results obtained by changing the relaxation rate of the matrix by means of the application of impermeable coatings that partially cover the matrix, and the overall result is that the original kinetics of the uncoated matrix is shifted towards constant release.
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The influence of substitution type on the performance of methylcellulose and hydroxypropylmethycellulose in gels and matrices
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Transport of penetrants in the macromolecular structure of coals
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Study of the swelling dynamics with overshooting effect of hydrogels based on sodium alginate-g-acrylic acid
TL;DR: In this article, a series of hydrogels were synthesized by graft cross-link copolymerization of sodium alginate (SA) and acrylic acid (AA) using N, N -methylene-bis-(acrylamide) as a crosslinker.
Journal ArticleDOI
Molecular transport characteristics of Santoprene thermoplastic rubber in the presence of aliphatic alkanes over the temperature interval of 25 to 70°C
TL;DR: In this paper, the Fickia-type mechanism was used to calculate the molar mass between crosslinks of the network polymer and the activation parameters for the process of diffusion, permeation and sorption/desorption.
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