SciELO - Scientific Electronic Library Online

 
vol.11 número3Compósitos Bioativos Obtidos a Partir da Inserção de Vidro Bioativo em Matriz de Poli(Metacrilato de Metila) índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

Compartilhar


Polímeros

versão impressa ISSN 0104-1428versão On-line ISSN 1678-5169

Resumo

DIAS, Marcos L.  e  SILVA, Alexandre P. F.. Chain Extention of Poly(ethylene naphthalate) with Triphenylphosphite. Polímeros [online]. 2001, vol.11, n.3, pp.102-108. ISSN 1678-5169.  http://dx.doi.org/10.1590/S0104-14282001000300008.

The reactive processing of poly(ethylene naphthalate) (PEN) in presence of triphenylphosphite (TPP) was investigated. An internal mixer coupled to a torque rheometer was used to monitor changes of molecular mass and temperature during processing. The torque curves revealed that chain extension reactions took place. During the processing, there is an increase in the molecular weight of the polyester, which reaches a maximum and then decreases due to molecular degradation, accelerated by the presence of chain extention by-products. The intensity of the chain extention reaction increases when TPP content, temperature and shear rate rise. Chain extension and degradation rate are slower in PEN than in poly(ethylene terephthalate). The presence of low molecular weight by-products of chain extension in PEN causes changes in the Tg, due to plasticization effects, and increase the crystallization rate.

Palavras-chave : Chain extention; polyesters; phosphites; PEN; PET.

        · resumo em Português     · texto em Português     · Português ( pdf )

 

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons