▁determ ining ▁the ▁contact ▁angle . ▁Contact ▁angles ▁closer ▁to ▁zero ▁indicate ▁a ▁more ▁w ett able ▁interaction , ▁and ▁those ▁interactions ▁have ▁a ▁greater ▁spread ability . ▁ ▁Ad s or ption ▁theory : ▁Ad s or ption ▁is ▁another ▁widely ▁accepted ▁theory , ▁where ▁ad hes ion ▁between ▁the ▁substr ate ▁and ▁ad hes ive ▁is ▁due ▁to ▁primary ▁and ▁secondary ▁bond ing . ▁The ▁primary ▁b onds ▁are ▁due ▁to ▁chem is or ption , ▁and ▁result ▁in ▁compar atively ▁long ▁last ing ▁c oval ent ▁and ▁non - c oval ent ▁b onds . ▁Among ▁c oval ent ▁b onds ▁dis ulf ide ▁b onds ▁are ▁likely ▁most ▁important . ▁Th i ol ated ▁polym ers ▁– ▁designated ▁th iom ers ▁– ▁are ▁mu co ad hes ive ▁polym ers ▁that ▁can ▁form ▁dis ulf ide ▁b onds ▁with ▁c yst e ine - rich ▁sub dom ains ▁of ▁m uc us ▁g ly cop rote ins . ▁Rec ently ▁several ▁new ▁classes ▁of ▁polym ers ▁have ▁been ▁developed ▁that ▁are ▁capable ▁of ▁forming ▁c oval ent ▁b onds ▁with ▁m uc os al ▁surfaces ▁similarly ▁to ▁th iom ers . ▁These ▁polym ers ▁have ▁ac ry loy l , ▁m eth ac ry loy l , ▁male im ide , ▁bor on ate ▁and ▁N ‐ h ydro xy ▁( s ul fo ) ▁succ in im ide ▁est er ▁groups ▁in ▁their ▁structure . Am ong ▁non - c oval ent ▁b onds ▁likely ▁ion ic ▁interactions