Construction of Mechanically Reinforced Thermoplastic Polyurethane from Carbon Dioxide-Based Poly(ether carbonate) Polyols via Coordination Cross-Linking.

Jincheng Dong,Gaosheng Gu,Zhongyu Duan,Binyuan Liu

doi:10.3390/polym13162765

Abstract

Using carbon dioxide-based poly(propylene ether carbonate) diol (PPCD), isophorone diisocyanate (IPDI), dimethylolbutyric acid (DMBA), ferric chloride (FeCl3), and ethylene glycol (EG) as the main raw materials, a novel thermoplastic polyurethane (TPU) is prepared through coordination of FeCl3 and DMBA to obtain TPU containing coordination enhancement directly. The Fourier transform infrared spectroscopy, 1H NMR, gel permeation chromatography, UV−Vis spectroscopy, tensile testing, dynamic mechanical analysis, X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis were explored to characterize chemical structures and mechanical properties of as-prepared TPU. With the increasing addition of FeCl3, the tensile strength and modulus of TPU increase. Although the elongation at break decreases, it still maintains a high level. Dynamic mechanical analysis shows that the glass-transition temperature moves to a high temperature gradually along with the increasing addition of FeCl3. X-ray diffraction results indicate that TPUs reinforced with FeCl3 or not are amorphous polymers. That FeCl3 coordinates with DMBA first is an effective strategy of getting TPU, which is effective and convenient in the industry without the separation of intermediate products. This work confirms that such Lewis acids as FeCl3 can improve and adjust the properties of TPU contenting coordination structures with an in-situ reaction in a low addition amount, which expands their applications in industry and engineering areas.

Highlights

Thermoplastic polyurethanes (TPUs) are one of the most interesting types of PUs with versatile applications ranging from consumer products, automobile parts, sporting goods, and electronic/medical devices [1,2,3,4,5]
Carbon dioxide-based polyol can be considered as polyether polyol modified by the introduction of carbonate structure, which is a kind of poly(ether carbonate) (PEC) polyols and combines the advantages of polycarbonate polyol and polyether polyol
It is demonstrated that PU obtained from carbon dioxide-based PEC polyols exhibit better hydrolysis resistance and oxidative stability compared with that based on petroleum polyester and polyether type polyols [12,13]

Summary

Introduction

Thermoplastic polyurethanes (TPUs) are one of the most interesting types of PUs with versatile applications ranging from consumer products, automobile parts, sporting goods, and electronic/medical devices [1,2,3,4,5]. Polyol is an essential component to generate the soft segments in polyurethane (PU) manufacture, which play significant roles in mechanical properties, chemical and oxidative stability for the resulted TPUs [6,7,8]. It makes sense to improve the mechanical properties of TPU from carbon dioxide-based polyols so as to expand the application fields. We aim at preparing TPU containing metal-coordination with an in-situ reaction and low addition amount of FeCl3 to expand its practical applications. Poly(propylene ether carbonate) diol (PPCD) chosen as a representative carbon dioxide-based PEC polyol, TPUs containing coordination enhancement possesses simultaneously high tensile strength and high toughness are successfully prepared by pre-polymerization through an in-situ method [31,32]. The chemical structures, thermal and mechanical properties of resulted polyurethane are inspected by Fourier transform infra-red (FT−IR) spectroscopy, 1H NMR, tensile testing, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA)

Materials

Preparation of TPU Reinforced with FeCl3 by Pre-Polymerization Method

Analysis and Measurements

Effect of DMBA on Mechanical Properties of TPU

Findings

Effect of FeCl3 on Polymerization Process of TPU