2006
DOI: 10.1590/s0100-40422006000400009
|View full text |Cite
|
Sign up to set email alerts
|

Avaliação da fotodegradação de poliolefinas através de exposição natural e artificial

Abstract: Recebido em 23/3/05; aceito em 13/9/05; publicado na web em 14/3/06 THE EVALUATION OF POLYOLEFIN PHOTODEGRADATION WITH NATURAL AND ARTIFICIAL EXPOSURE. Samples of polypropylene (PP) and low-density polyethylene (LDPE) were submitted to ultraviolet radiation, in the natural environment and also in the laboratory. Chemical modifications were quantified by the carbonyl index (CI), mechanical properties and melt flow index. The degradation in the laboratory was comparatively faster than in the environment for both… Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
3
1
1

Citation Types

0
12
0
19

Year Published

2013
2013
2024
2024

Publication Types

Select...
8
1
1

Relationship

0
10

Authors

Journals

citations
Cited by 32 publications
(31 citation statements)
references
References 29 publications
0
12
0
19
Order By: Relevance
“…The laboratory degradation analysis, using accelerated aging chamber, generally use standardized and controlled conditions. However, that are not equivalent to real situations of exposure or use, since is very difficult to simulate on laboratory the variability of natural elements such as temperature, radiation index, rainfall and wind [13].…”
Section: Introductionmentioning
confidence: 99%
“…The laboratory degradation analysis, using accelerated aging chamber, generally use standardized and controlled conditions. However, that are not equivalent to real situations of exposure or use, since is very difficult to simulate on laboratory the variability of natural elements such as temperature, radiation index, rainfall and wind [13].…”
Section: Introductionmentioning
confidence: 99%
“…Carbonyl groups resulting from the oxidation of polypropylene 30 and residues from the spin-off of ethylenebutylene links with styrene chains of SEBS 31 may have produced a favorable environment for adherence and proliferation of bacteria. Furthermore, although it was not verified in the FTIR profile, the waste layer of polymer degradation may have prevented contact between the bacterial cell and the additive.…”
Section: Chemical Propertiesmentioning
confidence: 99%
“…Já para o condicionamento UV, a Figura 06 apresenta a ocorrência de um comportamento linear de perda de massa, tal perda pode ser explicada pelo mecanismo de degradação do polietileno de baixa densidade, no qual a absorção de radiação UV por impurezas do polímero inicia uma sequência de reações químicas foto-oxidativas originando grupos químicos carbonila e hidroperóxidos, que por sua vez contribuem para o processo de reticulação e cisão de cadeias, consequentemente levando a degradação fotoquímica do material [24]. Apesar do condicionamento ter sido realizado intercalando períodos de 8 horas sob radiação UV e 8 horas de condensação, a despeito da condensação promover ganho de massa nas amostras pela retenção de umidade, predomina a degradação por UV.…”
Section: Condicionamento Ambientalunclassified