Improved Surface Energy Analysis for Plasma Treated PET Films (original) (raw)

Effects of operating parameters on plasma-induced PET surface treatment

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2008

Plasma treatment is widely used to modify the surface properties of polymers, since it is a versatile, fast and environmentally benign technology. Different types of plasma sources can be utilized for surface modification, however, dielectric barrier discharges (DBDs) have received much attention due to their great flexibility. Therefore, in this paper, a DBD operating in air at medium pressure is used to modify the surface of a polyethylene terephthalate (PET) film. The influence of the main operating parameters (discharge power, gas flow, pressure and frequency) on the surface properties is studied in detail using contact angle measurements. Results show that the efficiency of the surface treatment increases with increasing discharge power, increasing pressure and decreasing gas flow. Results also show that the frequency of the discharge has no influence on the treatment efficiency.

Surface energy increase of oxygen-plasma-treated PET

Materials Characterization, 2003

Prosthetic composite is a widely used biomaterial that satisfies the criteria for application as an organic implant without adverse reactions. Polyethylene therephthalate (PET) fiber-reinforced composites have been used because of the excellent cell adhesion, biodegradability and biocompatibility. The chemical inertness and low surface energy of PET in general are associated with inadequate bonds for polymer reinforcements. It is recognized that the high strength of composites, which results from the interaction between the constituents, is directly related to the interfacial condition or to the interphase. A radio frequency plasma reactor using oxygen was used to treat PET fibers for 5, 20, 30 and 100 s. The treatment conditions were 13.56 MHz, 50 W, 40 Pa and 3.33 Â 10 À 7 m 3 /s. A Ramé-Hart goniometer was used to measure the contact angle and surface energy variation of fibers treated for different times. The experimental results showed contact angle values from 47j to 13j and surface energies from 6.4 Â 10 À 6 to 8.3 Â 10 À 6 J for the range of 5 to 100 s, respectively. These results were confirmed by the average ultimate tensile strength of the PET fiber/ polymethylmethacrylate (PMMA) matrix composite tested in tensile mode and by scanning electron microscopy.

The mechanism of adhesion and printability of plasma processed PET films

Materials Research Innovations, 2003

Of the several techniques available for the surface modification, plasma processing has proved to be very appropriate. The low temperature plasma is a soft radiation source and it affects the material only over a few hundred deep, the bulk properties remaining unaffected. Plasma surface treatment also offers the advantage of greater chemical flexibility. PET films are widely used for packaging and electrical insulation. The studies of adhesion and printability properties are important. In the present study PET films are treated in air plasma for different time of treatment. The improvement in adhesion is studied by measuring T-peel and Lap shear strength. In addition, printability of plasma treated PET films is studied by cross test method. It has been found that printability increases considerably for plasma treatment of short duration. Therefore it is interesting to study the surface composition and morphology by contact angle measurement, ESCA and AFM. Surface energy and surface roughness can be directly correlated to the improvement in above-mentioned surface related properties. It has been found that the surface oxidation occurs containing polar functional groups such as C-O, COO. A correlation of all such observations from different techniques gives a comprehensive picture of the structure and surface composition of plasma treated PET films.