Controlled degradation and crosslinking of polypropylene induced by gamma radiation and acetylene

Autor(es)

Yoshiga, Adriana ^[1] ; Otaguro, Harumi ^[1] ; Parra, Duclerc Fernandes ^[1] ; Lima, Luis Filipe C. P. ^[1] ; Lugao, Ademar B. ^[1]

Afiliação do(s) autor(es)

^[1] IPEN, CNEN, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: POLYMER BULLETIN; v. 63, n. 3, p. 397-409, SEP 2009.
• Citações Web of Science: 26

Resumo

Isotactic polypropylene (iPP) undergoes crosslinking and extensive main chain scissions when submitted to irradiation. The simultaneous irradiation of PP and acetylene is able to control chain scission and produce grafting. The grafted PP further reacts with PP radicals resulting in branching and crosslinking. In this work, commercial polypropylenes (iPP) of different molecular weights were irradiated with a (60)Co source at dose of 12.5 kGy in the presence of acetylene in order to promote the crosslinking. The mechanical and rheological tests showed a significant increase in melt strength and drawability of the modified samples obtained from resins with high melt flow index. The characterization of the molecular modifications induced by gamma irradiation of isotactic polypropylenes under acetylene atmosphere proved the existence of branching, crosslinking and chain scission in a qualitative way. The G' and GaEuro(3) indicated the presence of LCB in all samples. Therefore, PP irradiation under acetylene was proved to be an effective approach to achieve high melt strength polypropylene (HMSPP). (AU)

• Processo FAPESP: 02/13070-2 - Pesquisa e desenvolvimento de um processo de síntese do polipropileno com alta resistência do fundo (HMS-PP) em presença de monômeros multifuncionais líquidos
• Beneficiário: Harumi Otaguro
• Modalidade de apoio: Auxílio à Pesquisa - Pesquisa Inovativa em Pequenas Empresas - PIPE