Preparation and characterization of a new class of poly(ether‐block‐amide)s via solvent free reactive processing

Abstract

Novel poly(ether-co-amide) block copolymers (PEA) with polyamide-6 as hard segments and different polyether (polyoxytetramethylene glycol [PTMG]/polyethylene glycol [PEG]) as soft segments were prepared via reactive processing. The chemical structure, crystalline properties, mechanical properties, water resistance, and thermal stability of as-prepared PEAs were extensively studied by Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, dynamic mechanical analysis, tensile testing, water contact angle, water absorption, and thermal gravity analysis. Fourier transform infrared spectroscopy confirmed the chemical structure and composition of PEAs. The X-ray diffraction and differential scanning calorimetry showed that PEAs consist of obvious crystalline polyamide-6 hard segments and that the crystalline structure of PEG will be significantly changed with the addition of PTMG. Dynamic mechanical analysis and tensile testing showed that the obtained PEAs exhibit classical elastomeric rubber plateau and tensile behavior. Meanwhile, the introduction of PTMG will improve the mechanical properties of PEAs. PEA with PEG as soft segments exhibited extremely surface hydrophilicity and high water absorption of 127%; the increasing of PTMG content in soft segments will reduce the surface hydrophilicity and improve the water resistance. In addition, the obtained PEAs exhibited good thermal stability, which will meet requirement of multiple processing. 1-4 Polyamide-based block copolymers usually consist of polyamide as hard segments and polyether or polyester as soft segment. [5][6][7][8][9][10] According to the practical application, polyamide-6 (PA6), polyamide-12, polyamide-66, polyamide-610, and other polyamides can be selected as the hard segments in the polyamidebased block copolymer. 4,11,12 Compared with other hard segments in the block copolymer, polyamide hard segments possess stronger hydrogen bonding and intermolecular forces, which will impart the block copolymer high melting temperature (T m ), organic solvent resistance, thermal resistance, abrasive resistance, etc. 13-15The oligomeric prepolymers with low glass transition temperature (T g ) were frequently used as the soft segments in the polyamide-based block copolymer in the previous study. ; and PEG is well known for its hydrophilicity, nontoxicity, and biocompatibility.24 Therefore, it is interesting and significant to tune the chemical and physical properties of polyamide-based block copolymers through variation in soft segments structure and molecular weight.In this study, the poly(ether-co-amide) block copolymers (PEAs) with PA6 as hard segments and polyether diol as soft segments are prepared through reactive processing without any solvent. Polyethylene glycol is selected as soft segments to enhance the hydrophilicity of PEAs, and the PTMG is introduced into the soft segments to improve the water resistance and mechanical properties of PEAs. The as-prepared PEAs are studied by Fourier transform infrared spectro...

A new class of poly(ether‐block‐amide)s based on semi‐aromatic polyamide: synthesis, characterization and structure–property relations

“…Generally, low glass transition temperature ( T g ) oligomers such as poly(tetramethylene glycol) (PTMG), 14 poly(ethylene glycol) (PEG), 23 poly(propylene glycol), 24 polydimethylsiloxane (PDMS) 25 and polyester 26, 27 are employed as soft segments. As for the hard segments, most of them have strong polar groups, such as urethanes, ureas, imides and esters 28 .…”

Synthesis, Characterization and Non-Isothermal Crystallization Kinetics of a New Family of Poly (Ether-Block-Amide)s Based on Nylon 10T/10I

“…The soft segment, acting with high elasticity to TPAE, presents a random coil configuration [ 1 , 4 , 5 ]. The hard segments, acting as physical cross-linking points, are either glassy or crystalline at room temperature [ 6 , 7 ]. At present, aliphatic polyamides such as PA-6, PA-11 and PA-12 are selected as the hard segments for commercial TPAEs [ 5 , 8 , 9 ].…”

“…According to this method, many kinds of TPAE have been successfully fabricated [ 5 , 10 ]. The advantage of this method is that the condition of reaction is mild [ 6 ]. However, the reaction is accompanied by the production of CO 2 , which is very difficult to remove with the high viscosity of the copolymer [ 10 ].…”

A Novel Semiaromatic Polyamide Thermoplastic Elastomer with Excellent Heat Resistance and Mechanical Properties

“…However, previous studies on aliphatic polyamide TPAEs have shown that the properties are not limited to changes in the molecular structure of the hard segment, 21,28,32,38,39 but also changes in the molecular weight of both the soft and hard segments. 1,29,40 Thus, in this study, PAPXD14/1214-PTMG elastomers were successfully prepared by controlling the molecular weight of the soft and semiaromatic polyamide hard segments. Meanwhile, the strategy of adjusting the benzene ring content in the semiaromatic polyamides was proposed to realize comprehensive improvement, as shown in Schemes 1 and 2.…”