TAILIEUCHUNG - A DSC/TGA study of the heterogeneous nucleation of crystallization in polypropylene copolymer

The study is aimed at the evaluation of the influence of nucleating agent (t-butyl)benzoic aluminum (NA) in changing clarity, crystallization temperature (Tp) and radiation resistant properties of polypropylene copolymer, PP (co) with 6% of ethylene. | Journal of Chemistry, Vol. 45 (5), P. 652 - 655, 2007 A DSC/TGA STUDY OF THE HETEROGENEOUS NUCLEATION OF CRYSTALLIZATION IN POLYPROPYLENE COPOLYMER Received 27 December 2006 Dang Duc Nhan, Tran Minh Quynh and Nguyen Hong Quy Institute for Nuclear Science and Technology summary The study is aimed at the evaluation of the influence of nucleating agent (t-butyl)benzoic aluminum (NA) in changing clarity, crystallization temperature (Tp) and radiation resistant properties of polypropylene copolymer, PP (co) with 6% of ethylene. It has been shown that crystallization temperature of PP (co)+NA did not change when the content of the NA less than 2%, but the super cooling temperature is a little bit increased when the content of the NA was 2 or higher than 2%. Clarity of the blend comprising of PP (co)+NA decreases with the addition of 2% or more NA (t-butyl)benzoic aluminum. However, the increase of the supercooling temperature makes possible to improve radiation resistance of the material. II - EXPERIMENTAL I - INTRODUCTION Nucleating agents are added to polypropylene (PP) in order to obtain optimum physical properties. It has been reported that the addition of nucleating agent changes the polymer’s crystallization temperature, spherulite size, density, clarity, impact and tensile properties considerably [1]. In this paper we report crystallization of a random copolymer of PP with 6% ethylene with a nucleating agent (NA), (t-butyl)benzoic aluminum, with its content varying from to 2%. The random copolymer of PP with 6% ethylene has been particularly selected in view of its reported improved radiation stability compared to pure polyethylene due to lower crystallinity of the former [2]. Various crystallization parameters were estimated from Differential Scanning Calorimetry (DSC). Thermo-Gravimetric Analysis (TGA) has been carried out to assess thermal stability conferred upon propylene copolymer by the addition of nucleating agent. 652 1. Materials Polypropylene .

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