Effect of Foaming Temperature on Microstructure, Mechanical Properties and Flame Spread Rate in PET–PEN Copolymer

Abstract

Polymer foams are expanding their applications into functional materials. Partial foam structure has been fabricated in polyethylene terephthalate–polyethylene naphthalate (PET–PEN) copolymer by solid state foaming. Through SEM image analyses, a potential to fabricate gradient foam structures with micropores and unfoamed skin layers has been identified. The post-foaming temperature Tf tune the pore size distribution. Radial distribution of micromechanical properties, indentation hardness and elastic modulus were measured for the partial foam and their values were around 0.12 GPa and 2.0 GPa, respectively, for the outer foamed region. Foaming temperature affects the glass transition temperature Tg, the coefficient of thermal expansion and the flame spreading rate. For the range of Tf ≤ 60°C, thermal expansion coefficients for T> Tg are about 0.5 m/m°C (steep expansion group, SEG). When Tf is above 80 °C, they are around 0.02 m/m°C (mild expansion group, MEG). The burning rate of SEG is 2.8 times higher than that of MEG.

Pengaruh Waktu Pemanasan terhadap Kesesuaian Warna dan Tebal Kulit Sintetis berbasis Polivinil Klorida

“…Suhu yang tidak sesuai dapat mengakibatkan degradasi dari material yang menyebabkan warna lebih gelap (Wen et al 2015). Lebih lanjut lagi, waktu dan suhu pengovenan juga dapat mempengaruhi distribusi gas, karakteristik fisis dan mekanik, serta adsorpsi-desorpsi blowing agent dalam pembentukan pori (Bomberg et al 1991;Park et al 2021). Oleh karena itu, tulisan ini bertujuan untuk mempelajari keterkaitan antara waktu pemanasan dengan warna dan tebal produk akhir kulit sintetis.…”

Influence of the Foaming Process on the Burning Behavior of the PET–PEN Copolymer

“…According to previous research on the two-step PET−PEN copolymer foam, a good correlation exists between the thermal expansion and flame spread rate of PET−PEN microrods. 1 Thermal expansion of the foam is categorized into two distinct groups: the steep expansion group (SEG) and the mild The vacuum insulation panel is a candidate insulating material for zero-energy houses because of its low thermal conductivity. 1 It consists of a core made of glass fiber or polyurethane foam.…”

“…1 Thermal expansion of the foam is categorized into two distinct groups: the steep expansion group (SEG) and the mild The vacuum insulation panel is a candidate insulating material for zero-energy houses because of its low thermal conductivity. 1 It consists of a core made of glass fiber or polyurethane foam. Recently, the use of PET−PEN as a VIP component material was proposed.…”

“…After the CO 2 concentration in the sample has reached the desired value, the pressure is quickly released at a relatively low temperature to prevent the sample from foaming. Then, the sample is immersed in an oil bath at the foaming temperature, T f , to trigger foaming . This procedure takes up to several days to produce PET–PEN copolymer foams.…”

“…According to previous research on the two-step PET–PEN copolymer foam, a good correlation exists between the thermal expansion and flame spread rate of PET–PEN microrods . Thermal expansion of the foam is categorized into two distinct groups: the steep expansion group (SEG) and the mild expansion group (MEG).…”