Aramid fibers, plasma surface

Fig. 5.21. Surface amine concenlralion (O) of aramid fiber and ILSS ( ) of epoxy matrix composites as a function of ammonia plasma treatment time. After Brown et al. (1991).

Brown, J.R., P.J.C. Chappell, Z. Mathys (1991), Plasma surface modification of advanced organic fibers part I. Effects on the mechanical, fracture and ballistic properties of aramid/aramid composites. J. Mater. Sci. 26. 4172 178,... 

Y. Ren, C. Wang, and Y. Qiu. Influence of aramid fiber moisture regain during atmospheric plasma treatment on aging of treatment effects on surface wettability and bonding strength to epoxy. Appl. Surf. Sci., 253(231 9283-9289, September 2007. 

Surface Modification of Aramid Fibers by a Low Temperature Plasma to Improve Their Adhesion... 

In this study, in order to improve the adhesion properties of aramid fibers to rubber as matrix, nylon thin films were securely formed on the surfaces of the aramid fibers by a radio frequency ion-plating (RFIP) method which represents an application of low temperature plasma treatment. These fibers were coated with a RFL (resorcinol-formaldehyde-latcx) adhesive which has high affinity to both nylon and rubber The adhesion properties of the fibers to rubber were evaluated, and the effects of the RFIP method were confirmed by a comparison of the RFIP treated fibers with those subjected to the low temperature plasma treatment. The usefulness of such surface modification methods will be discussed. 

It is shown that the adhesion properties of rubbers can be enhanced by low temperature plasma treatment of the aramid fibers with inactive surfaces, and coating with RFL adhesive immediately after the treatment. 

Sheu G S and Shvu S S (1994) Surface modification of Kevlar 149 fibers by gas plasma treatment. Part II Improved interfacial adhesion to epoxy resin, J Adhes Sci Technol 8 1027-1042. de Lange P J, Akker P G, Maeder E, Gao S L, Prasithphol W and Young R J (2007) Controlled interfacial adhesion of Twaron aramid fibers in composites by the finish formulation. Compos Sci Technol 67 2027-2035. 

Brown J R and Mathys Z (1997) Plasma surface modification of advanced organic fibers. Part V Effects on the mechanical properties of aramid/phenolic composites, J Mater Sci 32 2599-2604. 

Fig. 4.19 SEI images show the result of plasma etching with argon (A) a glass fiber surface shows no ordered details (B) amorphous PET film with particles but no order (C) an orient crystalline PET fiber surface with lateral striations, and (D) an aramid surface also with lateral striations. The effect of plasma etching with oxygen is shown for a glass fiber surface (E) which reveals no detail and (F) an aramid fiber which exWbits a lateral striated texture.

Aramid fibers were subjeeted to a variety of surfaee treatments to improve the interfaeial stress transfer between a thermoplastie matrix and the treated fiber eomposite. Analytical techniques to characterize the effect of surface treatment included DSC, Optical Microscopy, AFM and micromechanical analysis using Raman spectroscopy. Correlations between the different analysis methods were identified. It was found that plasma modified and chloride grafted fibers had the largest degrees of transcrystallinity, highest nucleation rates and greatest interfaeial shear strength between fiber and matrix. 

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