Journal of Thermal Analysis and Calorimetry, Vol. 59 (2000) 425–432
THERMAL ANALYSIS APPLIED TO DISCARDED CAR
BUMPERS
E. B. Mano
*
, A. F. Martins and L. C. Mendes
Instituto de Macromoleculas Professora Eloisa Mano, Federal University of Rio de Janeiro
P. O. Box 68525, 21945-970 Rio de Janeiro, RJ, Brazil
Abstract
The thermal properties of discarded bumpers from standard grade automobiles were compared to the
corresponding data obtained from binary and ternary blends of virgin polyolefins of composition simi-
lar to the recycled product. After grinding and separating by specific gravity, the recycled material was
identified by DSC, DMTA, TGA and C NMR. We found that it contains three polymers: poly-
propylyene (PP) as the major component, ethylene, propylene, diene methylene terpolymer (EPDM)
and a small amount of high density polyethylene (HDPE).
Keywords: car bumpers, recovered plastic, recycled plastic, thermal properties
Introduction
The interest in the recycling of materials, particularly plastics, has increased continuously
as concern on Nature preservation extends throughout the world. Two good reasons for
this concern are the desire not to waste resources and the disposal of scrap materials
which may otherwise pollute the environment [1]. The recyclability of car components
has become as important as that of packaging waste. For many car makers, this is a re-
quirement that needs to be met before they will consider using some materials [2]. Car
manufacturers have increasingly turned to polymer materials as a mass reduction
method. Among the plastics used in vehicles, PP bumpers have been targeted for recy-
cling because of their large size [3]. PP has been used in increasing ratios in the molding
compound for bumpers due to its capability for manufacture and recycling [4]. Thermo-
plastic polyolefin (TPO) compounds, which are blends of elastomeric ethyl-
ene-propylene (EP) or ethylene, propylene, diene methylene terpolymers (EPDM) with
PP, are expanding their usage specially in bumpers, owing to their low cost and capability
of recycling. Recycled plastics from bumpers are finding applications in several areas,
even as new bumpers [2, 5].
In the present work, the identification of the recycled material from used car bump-
ers was carried out by DSC, DMTA, TGA and
13
C-6NMR, due to the similarity of the
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© 2000 Akadémiai Kiadó, Budapest
Akadémiai Kiadó, Budapest
Kluwer Academic Publishers, Dordrecht
Dedicated to Prof. Edith A. Turi in recognition of her leadership in eduction
* Author to whom all correspondence should be addressed.