Plasma-induced Graft Copolymerization Research Articles

PCL covered PP meshes plasma-grafted by sulfonated monomer for the prevention of postoperative abdominal adhesions

Abdominal hernia reparation constitutes the second surgical operation in the world with more than 20 million cases per year. However, in more than 50 % of all intra-abdominal operations, postoperative adhesions occur and result in important pain for patients. These adhesions take place after excessive deposition of fibrin between peritoneum and organs within the 7 days after the operation which occurs during the coagulation cascade. For this reason, therapeutic solutions are required to both prevent adhesion and limit the need for a second surgical step. Numerous techniques were described in the past few decades to design biomedical textile implants and, among them, electrospinning shows great interest due to the porous and nanometer diameter range structure of the obtained fibers. In parallel, cold plasma treatment can be used to activate and graft their surface with functional molecules, exhibiting for example antibacterial or anticoagulant properties. This work aims at functionalizing, biodegradable polycaprolactone (PCL) electrospun nanofibers covering polypropylene meshes (PPM) with 2-acrylamido-2-methylpropane sulfonic acid (AMPS) through cold plasma induced graft copolymerization. AMPS was chosen as it contains heparin-like segments, leading potentially to similar anticoagulant effect. First, electrospinning of PCL was optimized by varying process, solution and environmental parameters and allowed to select a solution of 12 % of PCL in formic/acetic acid mixture. The graft-copolymerization of AMPS was then optimized in terms of power and time of plasma treatment, as well as solution concentration, using experimental design, in order to obtain nanofibers rich in SO3H groups at their surface. At each step of the process, the material was thoroughly characterized proving the presence of AMPS onto the surface of the nanofibers. The cytocompatibility and anticoagulant properties, evaluated after sterilization, are promising for an anti-adhesive application of these nanofibrous mats with no release of cytotoxic compound.

Superhydrophilic and oleophobic membrane functionalized with heterogeneously tailored two-dimensional layered double hydroxide nanosheets for antifouling

Fouling is a common challenge to all membrane-based separation technologies. The current study demonstrated an antifouling membrane with a superhydrophilic but oleophobic (in air) characteristic, which was achieved through covalently tethering heterogeneously tailored two-dimensional layered double hydroxide (LDH) nanosheets to a polyvinylidene fluoride membrane surface. The nanosheets were in situ grafted with alternately arranged sodium 1-dodecanesulfonate (SDS) and 3-aminopropyltriethoxysilane (APTS) chains during preparation. Poly(methacrylic acid) (PMAA) was previously grafted on the membrane via plasma induced graft copolymerization as anchor sites for nanosheet binding. With a simple dip-coating operation, the surface-tailored LDH nanosheets could be bound to the membrane via cross-linking between the amine groups of APTS and carboxyl groups of PMAA. Ultimately, the long hydrophobic SDS and short hydrophilic APTS chains on the nanosheets formed a heterogeneous and infiltration selective (due to steric exclusion) surface on the membrane. As a result, the hydrophilic moieties on the membrane surface were much more accessible to water than to liquids of larger molecular size, thereby bringing about the superhydrophilic but oleophobic characteristic. The functionalization gave rise to both significantly enhanced wettability and hydrophilicity of the membrane, mainly owing to the increase of the electron donor component of surface energy (γAB−). Additionally, the functionalized membrane obtained a greater permeability without compromising its selectivity. Furthermore, as verified in both filtration tests with synthetic and practical foulant solutions, the superhydrophilic and oleophobic characteristic endowed the functionalized membrane with conspicuously greater cleaning efficiency and excellent capability in resisting irreversible fouling, suggesting promising applications in various fields.

In-line Plasma-induced Graft-copolymerization of Pentaerythritol Triacrylate onto Polypropylene

Pentaerythritol triacrylate (PETA) was successfully grafted onto the plasma-treated isotactic polypropylene (iPP) via the in situ melt processing. The X-ray photoelectron spectroscopy (XPS) results showed that the hydroxyl and carbonyl groups, and peroxides could be generated via plasma treatment. The content of free radical in plasma-treated iPP (PiPP) was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH). It was found that the resulting peroxides induced the grafting copolymerization of PETA onto iPP, and the grafted PETA promoted the formation of β-crystal in PiPP, which was evidenced by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) measurements, respectively.

Plasma-induced synthesis of chitosan-g-polyacrylamide and its flocculation performance for algae removal

ABSTRACTChitosan (CS)-g-polyacrylamide (PAM) is a highly efficient and environmentally friendly flocculant, which was synthesized through plasma-induced graft copolymerization of CS and acrylamide (AM). The effects of monomer concentration, AM:CS ratio, discharge power, discharge time, post-polymerization temperature, and post-polymerization time on the intrinsic viscosity, grafting ratio, and grafting efficiency of CS-g-PAM were investigated. The optimum conditions of graft copolymerization were as follows: 20% monomer concentration, 7:3 AM:CS ratio, 40 W discharge power, 90 s discharge time, 50°C post-polymerization temperature, and 24 h post-polymerization time. The structural characteristics of CS-g-PAM were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. CS-g-PAM exhibited better flocculation efficiency than the commercially available PAM in both diatomite-simulated wastewater and low-turbidity algal water. The optimal turbidity removal efficiency for the diatomite-simulated wastewater was 99.9%, which was obtained with 6 mg L−1 of CS-g-PAM at pH 11.0 and 250 s−1 of velocity gradient. In low-turbidity algal water, the optimal removal efficiencies for chlorophyll-a, turbidity, and COD were 93.6%, 94.5%, and 98.2%, respectively.

Graft copolymerization coating of methacryloyloxyethyl diphenyl phosphate flame retardant onto silk surface

Abstract This paper reports an efficient surface modification methodology to increase fire resistance properties of silk fabric performed by radio frequency (RF) plasma-induced graft copolymerization of vinyl phosphate ester as nanometer coating. Methacryloyloxyethyl diphenyl phosphate (MEDP) monomer was prepared and graft-copolymerized onto the surface of silk fabric by argon RF plasma at ambient temperature. Under optimum RF power (30 W), amounts of MEDP and N,N methylenebisacrylamide cross linking agent were varied to obtain optimum graft copolymerization conditions. Untreated and treated silk were characterized by attenuated total reflectance infrared (ATR-IR) spectroscopy to investigate their functional group characteristics. This showed a strong covalent attachment between the surface of silk and flame retardant material as the carbonyl functionality of the MEDP was clearly observed in the spectra. Scanning electron microscopic (SEM) analysis also showed grafted material as nanometer residue on silk surface. Thermogravimetric analysis (TGA) revealed that the decomposition of phosphorus compound which occurs at lower temperature than that of silk itself resulted in the formation of char which covers the surface of the fabrics. This protects the fabric surface from further burning, therefore, higher amounts of remaining materials were observed as char in all cases. Furthermore, the limiting oxygen index (LOI) increased from 25.5 for untreated to 28.0 (ca. 10%) for the MEDP-grafted silk. Higher amounts of char were also observed in the case of MEDP-treated silk. After 5 dry cleaning cycles, the LOI of the treated silk dropped only very slightly. Detailed analysis on structural and thermal properties as well as surface grafting efficiency are presented.

Highly Hydrophilic Polyvinylidene Fluoride (PVDF) Ultrafiltration Membranes via Postfabrication Grafting of Surface-Tailored Silica Nanoparticles

Polyvinylidene fluoride (PVDF) has drawn much attention as a predominant ultrafiltration (UF) membrane material due to its outstanding mechanical and physicochemical properties. However, current applications suffer from the low fouling resistance of the PVDF membrane due to the intrinsic hydrophobic property of the membrane. The present study demonstrates a novel approach for the fabrication of a highly hydrophilic PVDF UF membrane via postfabrication tethering of superhydrophilic silica nanoparticles (NPs) to the membrane surface. The pristine PVDF membrane was grafted with poly(methacrylic acid) (PMAA) by plasma induced graft copolymerization, providing sufficient carboxyl groups as anchor sites for the binding of silica NPs, which were surface-tailored with amine-terminated cationic ligands. The NP binding was achieved through a remarkably simple and effective dip-coating technique in the presence or absence of the N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC)/N-hydroxysuccinimide (NHS) cross-linking process. The properties of the membrane prepared from the modification without EDC/NHS cross-linking were comparable to those for the membrane prepared with the EDC/NHS cross-linking. Both modifications almost doubled the surface energy of the functionalized membranes, which significantly improved the wettability of the membrane and converted the membrane surface from hydrophobic to highly hydrophilic. The irreversibly bound layer of superhydrophilic silica NPs endowed the membranes with strong antifouling performance as demonstrated by three sequential fouling filtration runs using bovine serum albumin (BSA) as a model organic foulant. The results suggest promising applications of the postfabrication surface modification technique in various membrane separation areas.

플라즈마 처리된 폴리프로필렌 표면 위에 글리시딜메타크릴레이트의 에멀젼 그래프팅

Glycidyl methacrylate (GMA) was used to introduce epoxy groups on the surface of polypropylene (PP) plate, used as a substrate, through plasma-induced graft copolymerization. Emulsion polymerization was applied for graft copolymerization of GMA and was compared with conventional solution polymerization to confirm its effect. Plasma treatment conditions under one atmospheric pressure were fixed as follows; the RF power of 200 W, the treatment time of 30 sec, the Ar gas flow rate of 6 LPM, and the exposure time of treated PP samples in air of 5 min. For graft-copolymerization, GMA concentration, reaction temperature, and reaction time was optimized to maximize the grafting degree of GMA. The maximum grafting degree of GMA was obtained at the condition of 12%-GMA concentration, reaction temperature, and 5 hr-reaction time. Analysis results supported that the emulsion polymerization was more effective than the solution polymerization for grafting more GMAs on the surface of PP plate under the same reaction conditions.

Surface Nanomodification of Cotton Fiber for Flame Retardant Application

This paper presents efficient surface modification methodology to increase fire resistance properties of cotton by radio frequency (RF) plasma-induced graft copolymerization of vinyl phosphate ester as nanometer residue structure onto cotton surface. Methacryloyloxyethyl diphenyl phosphate (MEDP) monomer was synthesized and grafted onto the surface of cotton fabric by argon RF plasma at ambient temperature. Under optimum RF power (30 W), amounts of MEDP and N,N methylenebisacrylamide cross linking agent were varied to obtain optimum graft copolymerization conditions. Untreated and treated cotton were characterized by attenuated total reflectance infrared (ATR-IR) spectroscopy to investigate their functional group characteristics. This showed a strong covalent attachment between the surface of cotton and flame retardant material as the carbonyl functionality of the MEDP was clearly observed in the spectra. Scanning electron microscopic (SEM) analysis also showed grafted material as nanometer residue on cotton surface. Thermogravimetric analysis (TGA) revealed that the decomposition of phosphorus compound which occurs at lower temperature than the cotton itself resulted in the formation of char which covers cotton surface. This protects the fabric surface from further burning, therefore, higher amounts of remaining materials were observed as char in all cases. Furthermore, limiting oxygen index (LOI) had increased from 19 in untreated to 28 in grafted cotton. Detailed analysis on structural and thermal properties as well as surface grafting efficiency are presented.

Thermally On−Off Switching Membranes Prepared by Pore-Filling Poly(N-isopropylacrylamide) Hydrogels

Pore-filling N-isopropylacrylamide (NIPAAM) polymer hydrogels were successfully grafted onto track-etched polycarbonate (PC) membranes by plasma-induced graft copolymerization. The microstructure and morphology of the PC-g-PNIPAAM membranes were investigated by XPS, SEM, ATR-FTIR, TGA, and water flux experiments. The effective pore sizes were regulated by the volume change of the cross-linked PNIPAAM hydrogels in the temperature range around its lower critical solution temperature (LCST). The PC-g-PNIPAAM membranes demonstrated a fast and reversible valve switching mechanism in a small temperature range. The on−off water flux ratio became more significant with the increase of the monomer concentration. Contact angle results showed that the thermal-responsive gating characteristics of PC-g-PNIPAAM membranes were mainly dependent on the pore size change.

Plasma-Induced Graft Copolymerization of Poly(methacrylic acid) on Electrospun Poly(vinylidene fluoride) Nanofiber Membrane

Electrospun nanofibrous membranes (ENM) which have a porous structure have a huge potential for various liquid filtration applications. In this paper, we explore the viability of using plasma-induced graft copolymerization to reduce the pore sizes of ENMs. Poly(vinylidene) fluoride (PVDF) was electrospun to produce a nonwoven membrane, comprised of nanofibers with diameters in the range of 200-600 nm. The surface of the ENM was exposed to argon plasma and subsequently graft-copolymerized with methacrylic acid. The effect of plasma exposure time on grafting was studied for both the ENM and a commercial hydrophobic PVDF (HVHP) membrane. The grafting density was quantitatively measured with toluidine blue-O. The degree of grafting increased steeply with an increase in plasma exposure time for the ENM, attaining a maximum of 180 nmol/mg after 120 s of plasma treatment. However, the increase in the grafting density on the surface of the HVHP membrane was not as drastic, reaching a plateau of 65 nmol/mg after 60 s. The liquid entry permeation of water dropped extensively for both membranes, indicating a change in surface properties. Field emission scanning electron microscopy micrographs revealed an alteration in the surface pore structure for both membranes after grafting. Bubble point measurements of the ENM reduced from 3.6 to 0.9 um after grafting. The pore-size distribution obtained using the capillary flow porometer for the grafted ENM revealed that it had a similar profile to that of a commercial hydrophilic commercial PVDF (HVLP) membrane. More significantly, water filtration studies revealed that the grafted ENM had a better flux throughput than the HVLP membrane. This suggests that ENMs can be successfully engineered through surface modification to achieve smaller pores while retaining their high flux performance.

Preparation of a reticulated polyurethane foam grafted with poly(acrylic acid) through atmospheric pressure plasma treatment and its lysozyme immobilization

We successfully introduced peroxide groups onto the surface of PU(Polyurethane) foam(10 PPI) through one atmospheric pressure plasma treatment and sequentially grafted PAAc(poly(acrylic acid)) on the surface of PU through radical copolymerization. The plasma treatment can generate large amount of peroxides on the surface of PU foam and the peroxide groups act as initiators for further grafting of PAAc in the monomer solution. To introduce large amount of peroxides on the surface of PU foam, we studied the effect of plasma rf-power and treatment time on the maximum grafting of PAAc. Through this study, we found that the optimum plasma treatment condition was the rf-power of 100 W and the treatment time of 100 s. On the other hand, we also studied the effect of graft reaction conditions such as temperature, monomer concentration and reaction time on the change of grafting degree (GD). The GD increased with increasing temperature and increased with reaction time before it leveled off at 3 h after reaction started. At low concentration of AAc, the GD was very low but it showed a maximum at the monomer concentration between 60 and 70%. The surface of the modified PU foam was qualitatively and quantitatively analyzed through the use of FT-IR and weight measurement, respectively. We also observed the surface change before and after plasma induced graft co-polymerization through photo and SEM analysis. Finally, we confirmed that the PU foams grafted with PAAc successfully immobilized lysozyme and other proteins from hen egg white.

Plasma-induced graft co-polymerization of acrylic acid onto the polyurethane surface

We introduced carboxylic groups on the surface of polyurethane (PU) with the aid of oxygen plasma treatment and the post-grafting of acrylic acid (AAc) in an aqueous solution. After plasma treatment, PU was exposed to the air to generate peroxides. Peroxides were confirmed by the 1,1-diphenyl-2-picrylhydrazyl method. We chose different parameters of plasma treatment to get the optimum condition for introducing maximum peroxides on the surface. Peroxides are known to be the species responsible for initiating the graft co-polymerization when PU reacts with AAc to produce AAc grafted PU. The AAc grafted on the surfaces was characterized by water contact angle measurement, Fourier transform infrared by attenuated total reflectance and electron spectroscopy for chemical analysis and optical microscopy. After confirming a successful grafting of AAc, we studied the effect of reaction temperature, reaction time, monomer concentration and Mohr's salt on the grafting degree of AAc.

New membranes bearing pyridinic ligands by plasma graft polymerization

2′-(2-Pyridyl)ethyl methacrylate (2-PEMA) synthesized in our laboratory was grafted onto the surface of polyacrylonitrile (PAN) ultrafiltration membranes by plasma-induced graft copolymerization. He plasma was used to activate the surface of PAN membranes before the grafting reaction. The amounts of peroxides created by plasma treatment were determined using 2,2-diphenyl-1-picrylhydrazine (DDPH). Influences of plasma treatment power, time, monomer concentration, presence of inhibitor, and solvents on polymerization were investigated. Surface functionalization was characterized by FTIR–ATR, ESCA, SEM, and water-contact angles. Grafting yield was shown to increase with the monomer concentration and if a mixture of H2O/CH3OH was used. Hence, it was possible to show that plasma treatment was a good technique to introduce ligands with coordinating properties by modifying the surface of the PAN membranes. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 359–366, 1998

Surface characterization and biological properties study of silicone rubber membrane grafted with phospholipid as biomaterial via plasma induced graft copolymerization.

Poly(2-methacryloyloxyethyl phosphorylcholine) (pMPC) was grafted onto the surface of a silicon rubber (SR) membrane (pMPC-SR) by plasma induced grafted copolymerization (PIP). Argon plasma was used to activate the SR surfaces. Determination was also made of the influences of grafted copolymerization reaction time, reaction temperature, and monomer concentration on polymerization yield. The surface properties of SR were characterized by ATR-FTIR, ESCA, and SEM. In those analyses the ATR-FTIR spectra indicated that the pMPC grafted onto the SR surface at 1720 and 3300 cm(-1). The elemental composition and different carbon bindings on the surface of the SR were examined by ESCA. An increasing P1s/C1s value g was obtained in the grafted polymerization yield with a concentration of 0.05-0.5M of MPC in the isolated ethanol solution. The surface morphologies of pMPC-SR differed more than those of control and Ar plasma treated surfaces. The difference could have been caused by the homogeneous graft polymerization of pMPC onto the SR membrane. In the biological analyses, protein adsorption on pMPC-SR surfaces was reduced. The reduced level increased with an increase in the pMPC grafted amount. The epithelial cell attachment and growth onto these samples were suppressed. The blood compatibility for a series of pMPC-SR surfaces was examined by platelet adhesion. Blood platelet morphologies in contact with the high ratio of pMPC-SR surfaces were maintained, meaning that in this case the release reaction for platelets never occurred. Consequently, the high amount of pMPC-SR surface had excellent blood compatibility, further suggesting that prevention of adhesion, activation of platelets, and adsorption of blood protein could be achieved.

Surface characterization and biological properties study of silicone rubber membrane grafted with phospholipid as biomaterial via plasma induced graft copolymerization

Surface characterization and biological properties study of silicone rubber membrane grafted with phospholipid as biomaterial via plasma induced graft copolymerization

The surface characterization of mulberry silk grafted with acrylamide by plasma copolymerization

The effects of plasma-induced graft copolymerization and simultaneous plasma-treated graft copolymerization with acrylamide (AAm) on the structure of mulberry silk are investigated. Through scanning electron microscopy, transmission infrared (IR), and attenuated total reflectance-IR and x-ray photoelectron spectroscopy (XPS) studies, changes of the surface morphology, structure, and composition are observed. The results show that plasma-induced graft copolymerization has more influence on the original structure of silk than does simultaneous plasma-treated graft copolymerization. The former brings the AAm branch polymer into the main chain of silk by the initiation of some kind of oxygen and nitrogen groups formed by the plasma, but the latter directly forms the AAm branch or cross-linking polymers with oxygen and nitrogen groups on the silk surface. This is the reason for the high elastic recovery angle of silk fabric modified by the two plasma graft copolymerizations. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1713–1717, 1997

Ionic absorption of polypropylene functionalized by surface grafting and reactions

Plasma-induced surface graft copolymerization of acrylic acid on polypropylene fibers and the subsequent reactions of the grafted carboxylic groups are reported. The extents ofgrafting was controlled by the plasma conditions. Reactions of the carboxylic acid with selected amines resulted in ion-exchanging and chelating functionalities. In general, ion adsorption is enhanced by higher levels of grafting and by raising temperature during adsorption. The adsorption level and preferences among ions of these functionalized fibers depend on the structure of the functional groups, i.e., the structure of the spacer and terminal groups. The carboxylic acid groups of the PP-g-AA fibers which behave like weakly acidic ion-exchangers are attributed to the low metal ion adsorption and the lack of ion preference. The F1 fibers with flexible -CH 2 CH 2 - spacer and small terminal - OH in the functional group exhibits highest ion adsorption among all functionalized fibers studied here. With benzene spacers, metal adsorption can be enchanced by the electron-donating nature of the terminal group. With the same ester end group in the functional structure, F3 fibers which contain benzene ring spacers show higher ion adsorption than F4 and F5 which have CH 2 and NH spacers, respectively. The ion preference and adsorption ability of the functionalized fibers, i.e., equilibrium binding constants (K b ) and saturation constants (K g ) derived from adsorption isotherms, also depend on the functional group structures. K b increases with increasing grafting yield, increasing the electron donor atom in either terminal bonds or spacer, and reducing the steric hindrance of spacer. The K s values are affected by the accessibility of functional groups, the size of spacer, and the terminal group structure.

Surface modification of silicone rubber membrane by plasma induced graft copolymerization as artificial cornea.

In this study a highly biocompatible polymer membrane was prepared by surface modification. An artificial cornea was also developed for clinical applications. Silicone rubber (SR) membrane was grafted with hydrophilic monomers such as 2-hydroxyethyl methacrylate (HEMA) and acrylic acid by plasma induced grafted polymerization. Surface properties of the SR were characterized using secondary ions mass spectra, Fourier transform infrared/attenuated total reflection, and element spectra for chemical analysis. The corneal epithelial (CE) cell was cultured in vitro, and penetrating keratoplasty of albino rabbit cornea (in vivo) was performed to evaluate biological properties of modified SR membranes. The ability of the CE cell to attach onto various SR membranes was observed by inverted microscopy. The proliferation of CE cell was conducted in approximately 96 h. Experimental results indicated that the attachment and growth of CE onto SR-g-pHEMA (75 micrograms/ cm2) is enhanced. The morphologies of an attached CE cell are similar to those of a primary CE cell. In the in vivo study, the depth of anterior chamber was maintained 2 weeks after penetrating keratoplasty was performed with a SR grafted with pHEMA (210 micrograms/cm2). This phenomenon displayed a high biocompatibility of modified SR membrane with the CE cell. Furthermore, results in this study provide a valuable reference for application of the modified SR for an artificial cornea.

Preparation and characterization of a homobifunctional silicone rubber membrane grafted with acrylic acid via plasma-induced graft copolymerization

Polyacrylic acid (PAA) was grafted onto the surface of silicone rubber membrane (SR) by plasma-induced graft copolymerization (PIP). Ar-plasma was used to activate the surface of SR. Also, a determination was made of the influences of plasma treatment power, pressure, time, grafted copolymerization reaction time, and monomer concentration on polymerization yield. The surface properties of SR were measured by ATR-FTIR, ESCA, and SIMS. In those analyses, the elemental composition and different carbon bindings on the surface of SR were examined by ESCA with the amount of O1s/C1s being approximately 0.7 at 60 s by Ar-plasma treatment (60 W, 200 mtorr). The peroxide group introduced on SR was measured via 1,1-diphenyl-2-picryhydrazyl (DPPH). The optimum amount of peroxide groups was 6.85 × 10−8 mol/cm2 at 60 s of Ar-plasma treatment. The peroxide group (33D peak) was introduced onto the surface of SR by negative spectra of SIMS analysis after SR treatment by Ar-plasma. An increase was obtained in grafted polymerization yield with a region of 5 to 50% (v/v) of acrylic acid aqueous solution. Both sites of polyacrylic acid were detected after staining by toluidine blue O. That is, a homobifunctional membrane was developed via this surface modification method. © 1996 John Wiley & Sons, Inc.

Plasma-induced graft copolymerization of HEMA onto silicone rubber and TPX film improving rabbit corneal epithelial cell attachment and growth

A poly(2-hydroxyethyl methacrylate) (pHEMA)-grafted polymer film was prepared by plasma-induced graft copolymerization onto an elastic material, silicone rubber, and a plastic material, poly(4-methyl-1-pentene) (TPX). The control, Ar plasma-treated and pHEMA-grafted silicone rubber and TPX surfaces were characterized by ESCA, FTIR-ATR, SEM and contact angle techniques. ESCA verified the respective chemical shift of control and Ar plasma-treated films. The presence of the grafted pHEMA was also verified by ESCA. The introduction of pHEMA onto a hydrophobic support provided an adequate surface for rabbit corneal epithelium cell attachment and growth. Cell attachment and growth onto these surfaces were examined by light microscopy. Cell attachment onto the control and Ar plasma-treated surfaces was negligible, while improved attachment and growth of rabbit corneal epithelium cells was demonstrated on the pHEMA-grafted polymeric surface. At 72 h, the pHEMA-grafted silicone rubber surface attached and grew more cells as compared with those on a pHEMA-grafted TPX surface. The pHEMA-grafted silicone rubber surface demonstrated a confluent cell layer after 72 h.