Mechanical effects according to the type of poly(styrene-co-methyl methacrylate) copolymers at polystyrene/poly(methyl methacrylate) interfaces

The reinforcement of polystyrene and poly(methyl methacrylate) interfaces using alternating copolymers

“…This behavior has also been observed for ADCB measurements on PS/PMMA interfaces reinforced with P(Sran-MMA) copolymers [22,38]. Furthermore, ADCB test by Cho on the compositionally symmetric P(S-ran-MMA) demonstrate that G c gradually increases as the copolymer layer thickness is increased up to 900 nm [38]. This is surprising behavior, however, as the copolymer has formed a third layer in this regime, where there exist two separate interfaces, one between the copolymer and the polystyrene, the other between the copolymer and poly(methyl methacrylate).…”

“…This is presumably due to an increased interaction between the copolymer and both homopolymer layers as the copolymer layer thickness increases. This behavior has also been observed for ADCB measurements on PS/PMMA interfaces reinforced with P(Sran-MMA) copolymers [22,38]. Furthermore, ADCB test by Cho on the compositionally symmetric P(S-ran-MMA) demonstrate that G c gradually increases as the copolymer layer thickness is increased up to 900 nm [38].…”

“…Our interpretation of this result is that the increase in molecular weight, increases the effective number of entanglements per chain, N eff ; which has been shown to be directly responsible for the fracture toughness of a biphasic interface [13]. Also supporting this interpretation is an ADCB study by Bernard that showed that the effectiveness of P(S 0.7 -ran-MMA) as an interfacial strengthener increases with M w for four copolymers ranging from 1.60 £ 10 5 to 4.50 £ 10 5 g/mol [22] as well as work by Cho which also observed an increase in G c as a function of M w for compositionally symmetric P(S-ran-MMA) [38].…”

“…The effectiveness of random copolymers to reinforce polymers interfaces has also been widely investigated [11,12,15,21,22,[33][34][35][36][37][38] and was found to be dependent on the monomer composition [22]. In the case of PðS f -ran-MMA 12f Þ; where f is the monomer composition, the compositionally asymmetric P(S 0.7 -ran-MMA) displayed the greatest reinforcement of the PS/PMMA interface out of a range of P(S-ran-MMA) compositions studied [21].…”

Copolumers obtained by grafting of vinyl monomers on starch - influence of amines on synthesis and degradation processes in environment

“…THF rastvor poli(glicidil-metakrilata) koji je pripremljen ţivom anjonskom polimerizacijom na -45 0 C interagovao je sa ""ţivim"" lancima PS na -30 0 C pri čemu su dobijeni kalemljeni kopolimeri u kojima je kičma kopolimera polarna (poli(glicidilmetakrilat)) a bočne grane nepolarne (PS) [72]. UporeĎivanje čvrstine različitih tipova polimera na bazi PMMK i PS, uz korišćenje kalemljenih, blok i nasumičnih kopolimera pokazalo je da čvrstina kopolimera raste u sledećem redu: blok>kalemljeni>nasumični kopolimeri [73]. Blok kopolimeri PS i butadiena (SBS) su veoma značajni u industriji.…”