Random poly(ε‐caprolactone‐L‐alanine) by direct melt copolymerization

A series of random polyesteramides (PEAs) with a range of molar composition from 90/10 to 50/50 were synthesized by direct melt polycondensation of ε‐caprolactone and l ‐alanine. Their structure was fully characterized by Fourier transform IR and NMR spectroscopy. The resulting copolymers are completely amorphous with the exception of PEA‐90/10 which possesses a semicrystalline structure. These PEAs present increasing glass transition temperatures at increasing l ‐alanine contents and exhibit fairly good thermal stability with 10% mass loss temperatures reaching 315 °C. © 2020 Society of Industrial Chemistry     

Polyamides incorporating furan moieties. 5. Synthesis and characterisation of furan-aromatic homologues

2,2′-Bis (5-chloroformyl 2-furyl) propane and various aromatic diamines were used as monomers in the study of their interfacial polycondensation and the properties of the ensuing furanic-aromatic polyamides. The effects of such variables as the nature of the organic phase, the temperature, the reaction time, and the type and concentration of the catalyst were investigated as well as the properties of the polyamides in terms of structure, average chain length, T_g, T_m and thermal stability.     

Reversibly crosslinked self‐healing PCL‐based networks

Poly(ε‐caprolactone) (PCL)‐based thermoreversible networks with self‐healing properties were prepared through Diels–Alder (DA) and retro‐DA reactions. Bis‐ or Tris‐maleimide compounds and a series of copolymer(caprolactone‐diene) PCL_XF_Y (X: degree of polymerization and Y: furan‐average functionality) with Y between 2.4 and 4.9 were used. The successive sequences of formation and dissociation of polycaprolactone networks via DA and retro‐DA reactions were observed repeatedly by dynamic mechanical analyses (DMA) and their gel‐temperatures determined. The cross‐linking densities, thermal properties, and thermal reversibility of the PCL_XF_Y/multimaleimide polymers have been modulated by the structure and functionalities of the used diene and dienophile moieties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Swarm intelligence‐based radio resource management for V2V‐based D2D communication

Internet of Things is a promising paradigm that provides the future network of interconnected devices. Device‐to‐Device (D2D) communication, which is considered as an enabler for vehicle‐to‐everything applications, has become an emerging technology to optimize network performance. In this paper, we study the Radio Resource Management (RRM) issue for D2D‐based Vehicle‐to‐Vehicle communication. The RRM key role is to assure the proficient exploitation of available resources while serving users according to their quality of service parameters. An Ant Colony Optimization (ACO)‐based Resource Allocation (ACORA) scheme is proposed in this paper. Swarm intelligence algorithm ACO is adopted to reduce the computational complexity while realizing satisfactory performance. Simulation results show promising performance of our proposed ACORA scheme.     

Bridging the Gap Between Solution and Solid-State Chemistry: Molecular Recognition at the Liquid–Solid Interface

The basic mechanisms of transition metal complex (TMC) adsorption on oxide surfaces are now well rationalized. In particular, we have proposed earlier a simple classification based on the role of oxide surface groups in adsorption. However, as our knowledge of specific systems progresses, it appears that this picture has to be refined and that partners other than surface groups and metal ions may take an important part in governing adsorption phenomena. All of the ligands of the transition metal complex are important, even those at first sight unaffected by the adsorption reaction. The functional groups of the so-called “spectator” ligands may in fact establish their own interactions with the surface groups, giving rise to the notion of surface/complex interactional complementarity. This idea is illustrated with analogs from homogeneous coordination chemistry, and we discuss two examples from catalyst preparation that suggest that interactional complementarity also plays a role in this field.     

Quasi‐alternating polyesteramides from ε‐caprolactone and α‐amino acids

Glycine‐ɛ‐caprolactone‐based and α‐alanine‐ɛ‐caprolactone‐based polyesteramides with a strong tendency to form alternating sequences (degree of randomness = 1.64 and 1.31) were synthesized by melt polycondensation of intermediate hydroxy‐ and ethyl ester‐terminated amides. These intermediates were synthesized by the reaction of equimolar amounts of ɛ‐caprolactone and glycine or L‐α‐alanine ethyl esters in mild conditions. The structure and microstructure of these polyesteramides are discussed on the basis of an in‐depth nuclear magnetic resonance study. Both polyesteramides are semi‐crystalline, but the glycine‐based one presents the highest melting enthalpy. This polyesteramide also exhibits higher Young's modulus and stress at break than its α‐ and β‐alanine counterparts. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44220.     

Polyamides incorporating furan moieties: 4. Synthesis,characterisation and properties of a homologous series

Interfacial polycondensation of 2,2′‐bis[2‐(5‐chloroformylfuryl)]propane with various diamines gave high yields of a novel series of furanic polyamides with high inherent viscosities. The properties of these polymers (T_g, surface energy, crystallinity, thermal stability) were assessed and examined in terms of the role of the specific structure of the bridging group borne by the diamines. Only three polyamides were partially crystalline, whereas all the others were amorphous. Thermogravimetric analysis revealed that thermal decomposition began above 300 °C in all instances. © 2001 Society of Chemical Industry     

Random polyesteramides based on ε‐caprolactone and glycine

A series of random polyesteramides (PEAs) based on ε‐caprolactone and glycine were synthesized by a direct melt polycondensation method. Their structure was fully characterized by NMR spectroscopy. High molar mass PEAs were obtained for glycine contents lower than 15 mol‐%. The resulting copolymers are semi‐crystalline and present increasing glass transition temperatures but decreasing melting points at increasing glycine contents. Some of these PEAs exhibit better thermal stability and higher Young's modulus and ultimate tensile strength than PCL homopolymer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40573.     

Polyamide-imides bearing furan moieties. 1. Solution polycondensation of aromatic dianhydrydes with 2-furoic acid dihydrazides

Novel polyamide-imides containing flexible segments were synthesized from aromatic dianhydrides and various furan dihydrazides by a two-steps procedure that included ring opening polyaddition to give polyhydrazide-acids, followed by thermal or chemical cyclodehydration. The polyhydrazide-acids had inherent viscosities ranging from 0.045 to 0.11 l/g. The polyamide-imides showed good solubility in aprotic polar solvents and had inherent viscosities up to 0.070 l/g, glass transition temperatures close to 250 °C and good thermal stability up to 350 °C.