Evaluation of 'Payne effect' in radiation-induced modification of chlorobutyl rubber
Carregando...
Data
Data de publicação
2010
Orientador
Título da Revista
ISSN da Revista
Título do Volume
É parte de
É parte de
É parte de
É parte de
MEETING OF THEN IONIZING RADIATION AND POLYMERS SYMPOSIUM, 9th
Exportar
Resumo
Butyl rubber (isobutylene and isoprene copolymer) has good properties including low
permeability to gases and good stability. Partially halogenated (Br and Cl) butyl rubber has been
used in a great variety of applications, such as tires parts (inner tube, internal coating of tires,
etc) and various products (lids, gaskets, etc.). In these compounds carbon-halogen bonds are
weaker than carbon-carbon and carbon-hydrogen bonds, and the main effect of radiation is to
break the carbon-halogen bond to give an organic free radical. Irradiations of certain alkyl
chlorides can bring about isomerism in which the location of the halogen atom is changed, the
carbon skeleton of molecule remaining unaltered. Irradiation of n-butyl chlorides gives high
yields of tertiary carbon. Due to the above behavior of low-molecular–weight alkyl halides,
butyl rubber, when exposed to high energy radiation exhibits significant degree of degradation
under ionizing radiation. The major effect of high energy photon, such as gamma rays, in
organic polymers is the generation of free radicals, along changes in electrical, optical and
mechanical properties. This work aims to the study of a controlled degradation of a chlorobutyl
rubber compound after irradiation at: 25, 100 e 200 kGy doses. Effects of irradiation on a rubber
compound were investigated via DMA (Dynamic Mechanical Analysis) tests using the so-called
Payne effect, which is directly related to the dynamic properties of the vulcanized rubber. The
test begins in a low strain excitation upwards to a maximum programmed strain, and then
downwards to a minimum strain at room temperature. The dependency of the material related to
the strain amplitude is illustrating by Payne effect. Material behavior presents a non linear
evolution on both modulus and Tan delta when increasing the strain (Payne effect) (Fig. 1). It
can be observed a difference on G’ and tangent delta values at low strain between the way up
and the way down of the sweeping. The difference between new material and irradiated material
at 25 kGy doses is not very significant. Nevertheless, it is verified the chain scission for higher
irradiation doses (≥ 25 kGy). Another interest in strain sweep is to make possible the detection
of strong breaking in materials linkage at high strain amplitude.
Como referenciar
SCAGLIUSI, S.R.; PARRA, D.F.; CARDOSO, E.C.L.; LIMA, L.S.C.E.; LUGAO, A.B. Evaluation of 'Payne effect' in radiation-induced modification of chlorobutyl rubber. In: MEETING OF THEN IONIZING RADIATION AND POLYMERS SYMPOSIUM, 9th, October 25-29, 2010, Maryland, USA. Abstract... Disponível em: http://repositorio.ipen.br/handle/123456789/21281. Acesso em: 30 Dec 2025.
Esta referência é gerada automaticamente de acordo com as normas do estilo IPEN/SP (ABNT NBR 6023) e recomenda-se uma verificação final e ajustes caso necessário.