Effects of acrylonitrile content and molecular weight on the scratch behavior of styrene‐acrylonitrile random copolymers

Abstract

Fundamental understanding of the scratch behavior of styrene-acrylonitrile (SAN) random copolymers with variation in acrylonitrile (AN) content and molecular weight (MW) is pursued using the methodology outlined in ASTM D7027-05/ISO 19252:08. Two sets of SAN model systems are employed: One that varies the AN content with similar MW and another that varies the MW at the same AN content. Key scratch damage mechanisms (scratch groove formation, periodic micro-cracking, and plowing) are identified and correlated with the compressive and tensile properties of the SAN systems. Scratch visibility is analyzed through the use of a commercial software package. A fundamental structure-property relationship of SAN scratch behavior is proposed by the fact that increasing the AN content or the MW can have a positive effect on increasing the scratch resistance of SAN as it improves its tensile strength and ductility. The implication of material properties and their effect on polymer scratch behavior is discussed.

Tribological Behavior of New Martensitic Stainless Steels Using Scratch and Dry Wear Test

“…In general, a lower SFC leads to higher scratch resistance [18]. The SFC can often give valuable clues to the location of transitions in scratch deformation mechanisms [14].…”

“…The scratch friction coefficient (SFC) was calculated by dividing the tangential force (F t ), continuously measured, by the applied normal force (F n ) [14] and allowed one to compare the scratch resistance of the tested materials. In general, a lower SFC leads to higher scratch resistance [18].…”

“…It has been used for many years to assess the adhesion of coatings to a specific substrate [11][12][13]. Scratch tests can also be used to characterize the wear [14], mimicking low or severe abrasion [15], where the typical mechanisms of abrasive action can be categorized as microplowing, microcutting and microcracking [16]. Moreover, the scratch process is assumed to be superposition of an indentation process and a sliding process where a relationship between the scratch resistance and the material properties can be established [17].…”

Quantitative modeling of scratch-induced deformation in amorphous polymers

“…Bellemare et al [18] reported a decrease in pile-up height (shoulder height) with the increase in strain hardening exponent using pure Copper and Copper/Brass alloy. Browning et al [2] showed that, using experimental study on styrene-acrylonitrile (SAN) random copolymers, an increase in acrylonitrile (AN) content or molecular weight (MW) can have a positive effect on improving the scratch resistance as it increases the tensile strength and ductility.…”

Tuning the modulus of nanostructured ionomer films of core–shell nanoparticles based on poly(n-butyl acrylate)

“…For those soft films it was shown that inclusion of AN was an effective method for tuning the modulus of the films 8 . AN is known to increase the surface hardness 25 , modulus 26 and tensile strength 27 and thermal stability 28,29 of copolymers due to the strong polarity of nitrile groups 28 and strong molecular interactions 30 . However, all of our previous nanostructured ionomer films used Bd as the main structural monomer 9,23,24 .…”