Influence of microwave plasma treatment on the surface properties of carbon fibers and their adhesion in a polypropylene matrix

Abstract

Fatigue variation of surface properties of silumin subjected to electron-beam treatment S V Konovalov, K V Aksenova, V E Gromov et al. -The effect of erosion and abrasion on surface properties of composite resin S Stoleriu, S Andrian, G Pancu et al. Abstract. A commercially available carbon fiber (CF) with an epoxy-based sizing (EP-sized CF) and an unsized CF have been plasma treated to study the effect on the fiber-matrix adhesion towards a polypropylene matrix. The EP-sized fiber was chosen because of its predictable low adhesion in a polypropylene (PP) matrix. The fibers have been modified using a microwave low-pressure O 2 /CO 2 /N 2 -gas plasma source (Cyrannus ® ) developed at IWS in a batch process. One aim of this study was the evaluation of parameters using high energies and short time periods in the plasma chamber to see the effect on mechanical performance of CF. These results will be the fundamental work for a planned continuous plasma modification line. The CF surface was characterized by determining the surface energies, single fiber tensile strength and XPS analysis. The adhesion behavior before and after plasma treatment was studied by single fiber pull-out test (SFPO) and scanning electron microscopy (SEM). It was shown that the CO 2 -and O 2 -plasma increases the number of functional groups on the fiber surface during short time plasma treatment of 30 s. Carboxylic groups on the unsized CF surface resulting from O 2 -plasma treatment lead to an enhanced fiber-matrix adhesion, whereas the fiber strength was merely reduced.

Comparison of the Influence of Two Types of Plasma Treatment of Short Carbon Fibers on Mechanical Properties of Epoxy Composites Filled With These Treated Fibers

“…After MW plasma treatment after an exposure time of 1 min, deepening and highlighting the striated fiber surface occurred. Similar highlighting of the striated surface was also reported in [16][17][18].…”

Simultaneously increasing the hydrophobicity and interfacial adhesion of carbon fibres: a simple pathway to install passive functionality into composites

“…[1][2][3][4][5] There have been considerable efforts in the manipulation of carbon bre surface chemistry to increase the bre-to-matrix adhesion using wet chemical oxidation, electrochemistry, plasma, and ozone, among others. [6][7][8][9] There is a substantial body of work which proposes that increasing the hydrophilicity (or surface polarity) of carbon bres correlates to enhanced interfacial adhesion. [9][10][11][12][13][14] This correlation has permeated the composite literature and is born from the idea that polar functional groups, such as carboxylic acids (COOH), ketones (C]O), phenols (PhOH), and other oxygenated species, facilitate efficient 'wet-out' of the bres by the supporting polymer.…”

Fiber with Butterfly Wings: Creating Colored Carbon Fibers with Increased Strength, Adhesion, and Reversible Malleability

“…Thus, the onus falls on the fiber surface to increase the adhesion in these components. Approaches such as plasma treatment [34][35][36][37] , chemical oxidation [38][39][40][41] , electrochemical [42][43][44][45][46][47][48] , and 'wet' chemical modification [44][45][46][47][48][49][50][51][52][53] , have previously been used to modify the surface of carbon fibers with limited success. The cost, time investment, and poor scale-up logistics make these processes difficult to retrofit to existing carbon fiber manufacturing equipment and have therefore had minimal impact on the industry.…”