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  1. ABSTRACT

    Shape memory polymers (SMPs) are a class of responsive polymers that have attracted attention in designing biomedical devices because of their potential to improve minimally invasive surgeries. Use of porous SMPs in vascular grafts has been proposed because porosity aids in transfer of fluids through the graft and growth of vascular tissue. However, porosity also allows blood to leak through grafts so preclotting the materials is necessary. Here hydrogels have been synthesized from acrylic acid andN‐hydroxyethyl acrylamide and coated around a porous SMP produced from lactose functionalized polyurea‐urethanes. The biocompatibility of the polymers used to prepare the cross‐linked shape memory material is demonstrated using anin vitrocell assay. As expected, the hydrogel coating enhanced fluid uptake abilities without hindering the shape memory properties. These results indicate that hydrogels can be used in porous SMP materials without inhibiting the shape recovery of the material. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1389–1395

     
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  2. ABSTRACT

    A lactose‐containing monomer,N‐(2‐lactosylethyl)acrylamide, was synthesized and polymerized withN‐hydroxyethyl acrylamide and 1 wt % ofN,N'‐methylenebis(acrylamide) and potassium persulfate as the initiator to produce hydrogels. The weight percent ofN‐(2‐lactosylethyl)acrylamide were increased from 0 to 100% in increments of 10%. Hydrogels were successfully produced with up to 90 wt % ofN‐(2‐lactosylethyl)acrylamide. Gelation was confirmed by inverted vial tests and rheology measurements. The as‐prepared hydrogels were used for papain stabilization against heat burden and papain that was loaded into hydrogels showed 45% more activity after heating as compared to papain that was heated without hydrogel stabilization. This hydrogel stabilization technique has potential applications in preserving enzyme activity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2016,54, 2507–2514

     
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