Social tie formation in Chinese online social commerce: The role of IT affordances

•Two types of social ties are proposed based on tie strength in online social commerce.•The effect of IT affordances, interactivity, and perceived effectiveness of e-commerce institutional mechanism on social ties formation are empirically tested.•Strong ties and weak ties are both positively related to repurchase intention in different degrees.•Perceived effectiveness of e-commerce institutional mechanism positively moderates the relationship between interactive and strong tie.•This study enriches IT affordance theory in interpreting buyer-seller social tie formation and extend research boundaries of impersonal relationship in online social commerce. Social media technology creates an opportunity to shift the formation of impersonal relationships from offline to online. The theory of IT affordances provides a basis for theorizing how the use of online social commerce (OSC) technology facilitates the formation of social ties in an OSC context. In this paper, integrating theories of IT affordances and social ties, we develop a model to explore how the six sub-dimensions of OSC IT affordances (i.e., visibility, metavoicing, triggered attending, guidance shopping, social connecting, and trading) aid buyers and sellers in building strong and weak OSC ties. A survey of 511 buyers from WeChat shows that five of the six IT affordances enhance the quality of interactivity, and thereby facilitate social ties (both strong and weak), which in turn contribute to buyers’ repurchase intentions. Additionally, the findings confirm the positive moderating effect of perceived effectiveness of e-commerce institutional mechanisms (PEEIM) on the strong tie formation process. This paper advances the affordances and social tie literature by examining the antecedents and outcomes of OSC social ties in more detail. Our findings not only benefit the researchers in interpreting how technology helps form different types of relationships in OSC, but also assists practitioners in developing better OSC management strategy.