Details

Autor(en) / Beteiligte

• Nguon, O.J.
• Charlton, Z.
• Kumar, M.
• Lefas, J.
• Vancso, G.J.

Titel

Interactions between sorbitol‐type nucleator and additives for polypropylene

Ist Teil von

• Polymer engineering and science, 2020-12, Vol.60 (12), p.3046-3055

Ort / Verlag

Hoboken, USA: John Wiley & Sons, Inc

Erscheinungsjahr

2020

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• The thermal properties of a sorbitol‐type nucleating agent (viz. 1,2,3‐trideoxy‐4,6:5,7‐bis‐O‐[(4‐propylphenyl)methylene]‐nonitol (TBPMN)) were examined in this study, and the influence of common processing additives assessed. In addition, we describe a novel approach to monitor in situ the self‐assembly of the nucleator in presence of additives by optical microscopy. The performance of sorbitol compounds is closely associated to their chemical structure and ability to self‐assemble. TBPMN formed elongated fibrils from the melt under inert atmosphere, in molted polypropylene, or in presence of antioxidants. However, calcium stearate (CaSt) and glycerol monostearate hampered growth, and yielded thinner fibrils. In presence of the additives, melting point depression of the nucleator occurred, and resulted in a lower degree of crystallinity upon cooling. Performance evaluation of the nucleator in polypropylene blends revealed an increased crystallization temperature when antioxidants were present, while CaSt inhibited nucleator activity. The effect of mono‐glycerides was found highly dependent on the processing conditions. Noteworthy, blends containing all the additives displayed the highest performance. This study highlights the importance of the preparation method of polymer additive blends to achieving the best performance in the final product. Characterization was performed by thermogravimetric analysis, Fourier‐transform infrared spectroscopy, optical microscopy, and differential scanning calorimetry. Nucleating or clarifying agents are added to improve the crystallization process and optical properties of polypropylene materials. Other additives are also of importance during processing, and include acid scavengers, antistatic agents, and antioxidants. By studying the self‐assembly of a sorbitol‐type nucleator and interactions with additives, we showed that synergistic interactions can improve the performance of the nucleator. Control over the structure of the nucleator is essential to obtain the best performance in the final product.