Abstract A series of thermoplastic polyurethane elastomers based on polycarbonate diol, 4,4′‐diphenylmethane diisocyanate and 1,4‐butanediol was synthesized in bulk by two‐step polymerization varying diol soft segment molecular weight chemical structure, also hard content, their effects the thermal mechanical properties were investigated. Dynamic analysis termogravimetric analysis, differential scanning calorimetry, Fourier transform infrared‐attenuated total reflection spectroscopy tests...

The degradation of two poly(ethylene terephtalate) (PET) samples from urban and marine wastes (PET-u PET-m, respectively) has been studied by comparing their properties with those virgin PET (PET-v) post-condensed for bottle fabrication (PET-ssp). FTIR spectroscopy, DSC analysis, WCA MFI results have confirmed that all residues were degraded. Therefore, the chemical recycling evaluated in order to valorize PET-m PET-u wastes, analyzing effect on process. Glycolysis degraded non-degraded...

Novel epoxy-based blends containing 30 wt % star styrene-b-butadiene block copolymers epoxidized at several degrees (SepB) have been investigated in order to analyze the effect of epoxidation degree on ability these produce nanostructures inside epoxy matrix as well their network structure matrix. For neat styrene−butadiene (SB) and SepB15-modified systems, macroscopic phase separation was observed. The SepB 40−76 mol %, however, yielded hexagonally ordered formed by PS cylinders arranged...

Novel nanostructured thermosetting materials have been prepared by modification of an epoxy resin with a semifluorinated diblock copolymer, poly(heptadecafluorodecyl acrylate)-b-poly(caprolactone), PaF-b-PCL. In first step, the phase behavior and linear viscoelasticity PaF-b-PCL were investigated. According to segregation regime, no order−order transitions detected, being order−disorder transition temperature beyond degradation temperature. Atomic force microscopy (AFM) images block...

Abstract The phase‐separation behavior and morphology of polycarbonate‐based polyurethanes were investigated as a function the soft‐segment molecular weight chemical structure 4,4′‐diphenylmethane diisocyanate/1,4‐butanediol based hard‐segment contents. Polarized optical microscopy atomic force images showed that surface morphologies changed content varied also when sample preparation conditions modified. An increase in soft‐ lengths led to increased phase separation with respect lower soft...

Electroconductive hydrogels (ECHs) have attracted interest for tissue engineering applications due to their ability promote the regeneration of electroactive tissues. Hence, ECHs with tunable electrical and mechanical properties, bioactivity, biocompatibility biodegradability are demanded. In this work, based on photo-crosslinked blends polyethylene glycol diacrylate (PEGDA) gelatin different PEGDA:gelatin ratios (1:1, 1.5:1 2:1 wt./wt.), containing poly (3,4-ethylenedioxythiophene):poly...

The growing appeal of carbon nanotube composites in the contemporary market derives from their exceptional thermal and chemical stability, coupled with electrical conductivity. In this study, we combined these salient features a biobased epoxy matrix having vitrimeric properties, hence being reprocessable resheapable, to obtain conductive coating. Epoxidised castor oil (ECO) was chosen as monomer precursor for straightforward synthesis. synthesis relied on cationic UV-curing process,...

ABSTRACT The objective of this work is to analyze the possibility thermomechanical recycling polyamide 6 (PA6) from fishing nets waste. effect processing on PA yarns obtained waste was investigated by means physicochemical, rheological, and thermal characterization. Infrared analysis indicated that chemical composition samples before after process maintained, also confirmed transitions detected calorimetry presence main peaks related γ α crystal phases polyamides at X‐ray diffraction...

The depolymerization process of PET by glycolysis into BHET monomer is optimized in terms reaction temperature and time, carrying out the under pressure to be faster for reducing energy required. Almost pure has been obtained working a reactor at 3 bar both 220 180 °C after short times, while longer ones mixture oligomers dimers obtained. Depending on potential application required, obtention different products controlled adjusting time. use allows work lower temperatures shorter obtaining...

The development of biobased resins for 3D printing has gained importance in recent years, driven by urgent environmental issues confronting our planet. derivatives glycerol represent a promising alternative to fossil fuels, holding central position the field polymer synthesis. In this background, polyglycerol-based acrylic monomers were synthesized Sakamoto Yakuhin Kogyo Co., Ltd. (Osaka, Japan). These monomers, which include groups, are sensitive UV light, and hence can be processed via...

Abstract Epoxy‐based blends containing poly(ethylene oxide)‐ co ‐poly(propylene ‐poly(ethylene oxide) (PEO–PPO–PEO) block copolymers with different PEO/PPO molar ratios have been investigated in order to analyze the effect of generated morphologies and interactions between components on mechanical properties blends. Mechanical, morphological dynamic analyses indicate that observed increase flexural modulus can be related decrease free volume. In modified systems remain miscible, an modulus,...

Abstract Several lignin (L)‐based novolac‐type phenolic prepolymers with two phenol (P) substitution degrees have been synthesized using three L from different origin (kraft pine L, soda/anthraquinone (AQ) flax and sulfonated kraft softwood L). These lignophenolic (LPF) resins characterized by means of free P formaldehyde (F) analysis, viscosity, chemical structure (FTIR), thermal behavior (DSC). Temperature at which curing reaction begins (DSC), hardening time several temperatures...

This work presents the synthesis of new poly(itaconate)s containing sulfone or nitrile pendant groups through conventional radical polymerization together with their characterization and comparison poly(methacrylate)s identical groups. Structural thermal has been carried out in terms Fourier transform infrared spectroscopy, differential scanning calorimetry, nuclear magnetic resonance, thermogravimetric analysis. Characterized by broad band dielectric spectroscopy (BDS), all polymers showed...

Three amines with different molecular structure, triethylenetetramine (TETA) and two polyetheramines (Jeffamine D-230 Jeffamine T-403) were employed to functionalize multi-walled carbon nanotubes (MWCNT) previously oxidized by acid treatment. The functionalized MWCNT characterized Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, UV-vis the surface modification was investigated field emission scanning electron microscopy (FE-SEM). Thermogravimetric analysis (TGA) quantify...

Abstract Nanostructure formation in thermosets can allow the design of materials with interesting properties. The aim this work was to obtain a nanostructured epoxy system by self‐assembly an amphiphilic diblock copolymer unreacted epoxy/amine mixture followed curing matrix. employed polystyrene‐ block ‐poly(methyl methacrylate) (PS‐ b ‐PMMA). thermoset system, formed diglycidyl ether bisphenol A‐type resin and diaminodiphenylmethane hardener, chosen ensure miscibility most PMMA until matrix...