Use of poly(ethylene‐co‐vinyl alcohol) as compatibilizer in LDPE/thermoplastic tapioca starch blends

Abstract

Poly(ethylene-co-vinyl alcohol) (EVOH) was used as a compatibilizer to make blends of low-density polyethylene (LDPE) and plasticized starch (TS). The tensile properties and impact strength were measured and compared with those of neat LDPE. The morphology of the blend specimens, both fractured and unfractured, was observed by scanning electron microscopy. Comparison of the properties showed that the impact strength of the blend improves significantly by the addition of a compatibilizer even with a high TS loading of 40 and 50% (by weight). A high elongation at break almost matching that of neat polyethylene was also obtained. The blend morphology of the etched specimens revealed fine dispersion of the starch in the polyethylene matrix, while the fracture surface morphology clearly indicate that the failure of compatibilized blends occurs mainly by the ductile mode.

Blendas compatíveis de amido termoplástico e polietileno de baixa densidade compatibilizadas com ácido cítrico

“…Embora o polietileno seja um dos polímeros de grande potencial para formar blendas com o amido termoplástico, a sua baixa polaridade leva a blendas de baixa compatibilidade e diversos estudos têm sido realizados com o objetivo de melhorar as características dessas blendas. Dentre esses estudos, se destaca a utilização de agentes compatibilizantes, tais como o poli(etileno-ganidrido maleico) (PE-g-MA) [21,22] , poli(etileno-co -vinil álcool) (EVOH) [23] , poli(etileno-co-ácido acrílico) (EAA), poli(etilenoco -metacrilato de glicidila) (PEGMA) [24][25][26] . Particularmente a compatibilização reativa, tem sido empregada mais recentemente e tem levado a resultados promissores [21][22][23][24][25][26][27] .…”

“…Dentre esses estudos, se destaca a utilização de agentes compatibilizantes, tais como o poli(etileno-ganidrido maleico) (PE-g-MA) [21,22] , poli(etileno-co -vinil álcool) (EVOH) [23] , poli(etileno-co-ácido acrílico) (EAA), poli(etilenoco -metacrilato de glicidila) (PEGMA) [24][25][26] . Particularmente a compatibilização reativa, tem sido empregada mais recentemente e tem levado a resultados promissores [21][22][23][24][25][26][27] . Em trabalho recente, demonstramos que os ácidos orgânicos, como o ácido ascórbico e o ácido cítrico podem ser utilizados diretamente no processamento do amido termoplástico gerando materiais com menor viscosidade no estado fundido [28] , abrindo novas possibilidades para a modificação do amido termoplástico.…”

Compatibilization of low‐density polyethylene/cassava starch blends by potassium persulfate and benzoyl peroxide

“…[27][28][29][30][31][32] To increase the compatibility of LDPE/starch blends, modified or nonnative starch has been used, such as pregelatinized starch, 11 crosslinked starch, 14 octanoated starch, 18,19,33 starch acetate, 20 hydropropylated starch, 21 and phthalated starch. 34 Polyethylene graft copolymers have been widely used as compatibilizers with other polymers; they include polyethylene grafted with maleic anhydride (PE-g-MA), 1,3,5,6,17,24,25,35,36 polyethylene grafted with glycidyl methacrylate, 10,27 LDPE grafted with dibutyl maleate, 31 LDPE grafted with itaconic acid, 32 an ethylene/acrylic acid copolymer, 16,37 and polyethylene grafted with styrene-co-maleic anhydride polymer.…”

Mechanical and thermal properties of EVA blended with biodegradable ethyl cellulose

“…The degree of hydrolysis was measured to be 89% as done earlier by Sailaja and Chanda. 13 Ethyl cellulose (EC) powder was obtained from Sigma Aldrich (USA). All other solvents were obtained from S.d.…”

“…11 To improve adhesion between the two phases, EVA was used as compatibilizer. 12,13 EVA compatibilized biodegradable starch-based composites were prepared by Senna et al 14 It was found that electron beam irradiation further improved the compatibility of the blends. EVA/Sisal fiber grafted composites showed good interfacial adhesions when compared with unmodified composites.…”