cial ▁ad hes ion ▁can ▁be ▁substantial ly ▁en hanced ▁via ▁a ▁coupling ▁agent ▁that ▁ad her es ▁well ▁to ▁both ▁the ▁polym er ▁and ▁the ▁fill er ▁particles . ▁ ▁The ▁type ▁and ▁amount ▁of ▁surface ▁treatment ▁on ▁the ▁fill er ▁are ▁thus ▁additional ▁parameters ▁affect ing ▁the ▁r he ological ▁and ▁material ▁properties ▁of ▁filled ▁polym er ic ▁systems . ▁ ▁It ▁is ▁important ▁to ▁take ▁into ▁consideration ▁wall ▁s lip ▁when ▁performing ▁the ▁r he ological ▁character ization ▁of ▁highly ▁filled ▁materials , ▁as ▁there ▁can ▁be ▁a ▁large ▁difference ▁between ▁the ▁actual ▁stra in ▁and ▁the ▁measured ▁stra in . ▁ ▁R he ologist ▁▁ ▁A ▁r he ologist ▁is ▁an ▁inter dis cipl inary ▁scient ist ▁or ▁engineer ▁who ▁studies ▁the ▁flow ▁of ▁complex ▁liqu ids ▁or ▁the ▁de formation ▁of ▁soft ▁sol ids . ▁It ▁is ▁not ▁a ▁primary ▁degree ▁subject ; ▁there ▁is ▁no ▁qual ification ▁of ▁r he ologist ▁as ▁such . ▁Most ▁r he olog ists ▁have ▁a ▁qual ification ▁in ▁mathematics , ▁the ▁physical ▁sciences ▁( e . g . ▁chem istry , ▁physics , ▁ge ology , ▁bi ology ), ▁engineering ▁( e . g . ▁mechanical , ▁chemical , ▁materials ▁science , ▁pl ast ics ▁engineering ▁and ▁engineering ▁or ▁civil ▁engineering ), ▁medicine , ▁or ▁certain ▁techn ologies , ▁not ably ▁materials ▁or ▁food . ▁Typ ically , ▁a ▁small ▁amount ▁of ▁r he ology ▁may ▁be ▁studied ▁when ▁obtain ing ▁a ▁degree , ▁but ▁a ▁person ▁working ▁in ▁r he