Poly 2-Hydroxyethyl Methacrylate PHEMA

Interpenetrating networks (IPNs) composed of different proportions of PCL and poly-2-hydroxyethyl methacrylate (pHEMA) have... 

Simple physical entanglements can be sufficient to produce a structurally stable gel if the polymer has a sufficiently great molecular weight and if the polymer is of only modest hydrophilicity. In this case, the polymer will swell in water without dissolving, even in the absence of covalent cross-links. Poly(2-hydroxyethyl methacrylate) (PHEMA) is a prominent example of this type of hydrogel when uncross-linked, it will dissolve in 1,2-propanediol but only swell in water. 

It is possible for Q or q to range from 1.2 to over 1000 this translates to an EWC range of 20% to over 99%. A commonly used hydrogel for drug delivery, poly(2-hydroxyethyl methacrylate) (PHEMA), has a q of about 1.7 or an EWC of about 40%. 

Poly(2-hydroxyethyl methacrylate) (PHEMA) has been the most widely used polymer in drug delivery applications. It is an extremely hydrophilic... 

An NIR optical fiber for the detection of metal ions has been developed In a controlled environment, the optical probe with immobilized NIR dye was immersed in vials containing different metal ions varying in concentrations from 10 9 to 1CT2 M. The probe response was obtained by the diffusion of the metal ions through the poly(2-hydroxyethyl methacrylate) (PHEMA) polymer matrix where the dye was covalently attached. On complexation of the metal with the dye, the intensity of the fluorescence signal increased. 

Fig. 11 Chemical formulas of poly(acryl amide) (PAAm), poly(methyl methacrylate) (PMMA), poly(2-hydroxyethyl methacrylate) (PHEMA), poly(t-butyl acrylate) (PtBA), and poly(acrylic acid) (PAA), and poly(dimethyl aminoethyl methacrylate) (PDMAEMA)...

Fig. 43 Dry thickness of poly(2-hydroxyethyl methacrylate) (PHEMA) as a function of the position on the substrate (lower panel). The fluorescence microscopy images show the corresponding structure of fibrinogen at three positions along the PHEMA gradient (upper panel). (Reproduced with permission from [164])...

The anionic polymerization of masked disilenes proceeds via living anions, and therefore block copolymerization with a conventional vinyl monomer is possible. Recently, interesting hydrophobic block copolymer of PMHS with poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(methacrylic acid) (PMMA) have been prepared (Scheme 11). These polymers can be self-assembled and are transformed into polysilane micelles, shell cross-linked micelles (SCM), and nanometer-sized hollow particles. ... 

Fig. 3. (a) Infrared spectrum of poly 2-hydroxyethyl methacrylate (PHEMA) on a salt (date glued into a gas phase IR cell, (b) Spectrum alter exposure to d4 methanol vapor. Arrows indicate major peaks moved by deu-teration... 

Recent experiments indicate that polymers that contain a balance of hydrophobic (nonpolar) and hydrophilic (polar) chemical groups show minimal protein adsorption and cell adhesion (6). With the intent of rationally designing a contact lens material that would minimize protein adsorption, the adsorption of lysozyme, albumin, and immunoglobulin G (IgG) to a series of hydrophobic and hydrophilic polymers and copolymers was measured. The polymers ranged from 100% poly(methyl methacrylate) (PMMA) to 100% poly(2-hydroxyethyl methacrylate) (PHEMA). Adsorption varied significantly for each protein, as did the elutability of the proteins from the surfaces. 

For biomedical applications, the most frequently encountered synthetic hydrogel is poly(2-hydroxyethyl methacrylate) (pHEMA). The characterization and applications of pFIEMA have been reviewed [4]. Both HEMA and pHEMA are easy and inexpensive to produce. Because of the primary alcohol, the monomer or polymer can be functionalized. In addition, HEMA can be copolymerized... 

These suppressive effects of SA copolymers on cellular adsorption and shape change were observed for rat lymphocytes as well as platelets (58,59). Figure 2 clearly demonstrates the elimination of adsorption of lymphocytes on albuminated surfaces of SA copolymers containing 9 wt% polyamine branches (SA9). A change in the back-bone structure of the graft copolymer from polystyrene to the more hydrophilic poly(2-hydroxyethyl methacrylate) (PHEMA)... 

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