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The morpheme-based model faces itself with troubles at describing discontinuous morphemes, as well as other ill-behaved morphemes from a structural point of view (empty, accumulative, substitutive, etc.). The analysis of the parasynthetic word-formation in Spanish results problematic because the notion of linearity is violated and the binary formation of the words is broken. In this paper, we present an analysis of the causative verbs in /enXar/ of the type embotellar, 'to bottle', through a model that establishes schematic relationships among words. Through the bidirectional scheme: [/enXar/V 'poner x'] ↔ [/X/N 'x'], (embotellar, 'to bottle') ↔ (botella, 'bottle'), that relates verbs with nominal forms, we demonstrate this analysis is more relevant from a cognitive point of view because it is more attached to the intuition of the speakers. [ABSTRACT FROM AUTHOR]

Chitosan-coated magnetic nanoparticles (CMNP) were obtained at 70 °C and 80 °C in a one-step method, which comprises precipitation in reverse microemulsion in the presence of low chitosan concentration in the aqueous phase. X-ray diffractometry showed that CMNP obtained at both temperatures contain a mixture of magnetite and maghemite nanoparticles with ~4.5 nm in average diameter, determined by electron microscopy, which suggests that precipitation temperature does not affect the particle size. The chitosan coating on nanoparticles was inferred from Fourier transform infrared spectrometry measurements; furthermore, the carbon concentration in the nanoparticles allowed an estimation of chitosan content in CMNP of 6%-7%. CMNP exhibit a superparamagnetic behavior with relatively high final magnetization values (~49-53 emu/g) at 20 kOe and room temperature, probably due to a higher magnetite content in the mixture of magnetic nanoparticles. In addition, a slight direct effect of precipitation temperature on magnetization was identified, which was ascribed to a possible higher degree of nanoparticles crystallinity as temperature at which they are obtained increases. Tested for Pb2+ removal from a Pb(NO3)2 aqueous solution, CMNP showed a recovery efficacy of 100%, which makes them attractive for using in heavy metals ion removal from waste water. [ABSTRACT FROM AUTHOR]

In lexical morphology, it is very common to find word-formation patterns that rival each other because they belong to the same conceptual field. This trait is more evident in the suffixation, the more productive word-formation process in Spanish. Derivation provides a large repertoire of competing schemes due to the overlap in meaning and function within the system. For instance, competition occurs between forming-verb suffixes -ción and -miento: agrupación and agrupamiento; financiación and financiamiento; aburrición and aburrimiento; detención and detenimiento, etc. Rivalry becomes more complex if we realize that there are other competing suffixes in the system: -dura (torcedura, torcimiento); -aje (almacenamiento, almacenaje). It is commonly stated that competition is resolved in favour of the more productive pattern. However, as productivity is relative and depends on many factors, the same pattern does not always prevail. This research aims to describe the phenomenon, note the source of some of these rivalries and propose relevant parameters and factors to define and characterize this process. We argue that most of these rivalries depends on structural factors and language use factors that interact in different ways and to various degrees. [ABSTRACT FROM AUTHOR]

The mechanical properties of different high impact polystyrene (HIPS) were determined by means of impact and tensile tests. Impact strength (IS), yield stress (σy) and Young's modulus (E) were evaluated as a function of the rubber phase morphological features such as type and particle size (Dp), volume fraction (Φ) and interparticle distance (IPD). In order to evaluate the changes produced in the rubber phase, the initiator, chain transfer agent (CTA), and type and concentration of SB copolymer were varied during the synthesis of HIPS. Transmission electron microscopy was used to analyze the materials' morphology and the data obtained reveal that the Dp and Φ increases mainly with an increase in the PB content and/or with the use of CTA and decreases with an increase in initiator concentration. In addition, E and yield stress diminishes when increasing the dimensions of the rubber phase (Dp and Φ), contrary to the IS. The IPD/Dp ratio also indicates the dependency of the mechanical properties with respect to the rubber phase features. An increase in IPD/Dp provokes an increases in E and σy, whereas IS diminishes. [ABSTRACT FROM AUTHOR]

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Three series of polyesters based on monomer combinations of ε -caprolactone ( ε -CL), ethylene brassylate (EB), and l-Lactide (LLA) with the alkyl substituted lactone ε -decalactone ( ε -DL) were synthesized at different molar ratios. Copolymers were obtained via ring opening polymerization (ROP) employing TBD (1,5,7-triazabicyclo-[4.4.0]-dec-5-ene), an organic catalyst which can be handled under normal conditions, avoiding the use of glove box equipment. The molar monomer composition of resulting copolymers differed from theoretical values due to lower ε -DL reactivity; their M n and M w values were up to 14 kDa and 22.8 kDa, respectively, and distributions were ( Ɖ ) ≤ 2.57. The thermal stability of these materials suffered due to variations in their ε -DL molar content. Thermal transitions such as melting ( T m ) and crystallization ( T c ) showed a decreasing tendency as ε -DL molar content increased, while glass transition ( T g ) exhibited minor changes. It is worth mentioning that changes in monomer composition in these polyesters have a strong impact on their thermal performance, as well as in their crystallization degree. Consequently, variations in their chemical structure may have an effect on hydrolyic degradation rates. It should be noted that, in future research, some of these copolymers will be exposed to hydrolytic degradation experiments, including characterizations of their mechanical properties, to determine their adequacy in potential use in the development of soft medical devices.

Polyaniline (PANI) composites have gained momentum as supercapacitive materials due to their high energy density and power density. However, some drawbacks in their performance remain, such as the low stability after hundreds of charge-discharge cycles and limitations in the synthesis scalability. Herein, we report for the first time PANI-Graphitic oxidized carbon nitride composites as potential supercapacitor material. The biomimetic polymerization of aniline assisted by hematin, supported by phosphorous and oxygen-modified carbon nitrides (g-POCN and g-OCN, respectively), achieved up to 89% yield. The obtained PAI/g-POCN and PANI/g-OCN show enhanced electrochemical properties, such as conductivity of up to 0.0375 S/cm, specific capacitances ( C s ) of up to 294 F/g (at high current densities, 5 A/g) and a stable operation after 500 charge-discharge cycles (at 3 A/g). In contrast, the biomimetic synthesis of Free PANI, assisted by stabilized hematin in cosolvents, exhibited lower performance properties (65%). Due to their structural differences, the electrochemical properties of Free PANI (conductivity of 0.0045 S/cm and C s of up to 82 F/g at 5 A/g) were lower than those of nanostructured PANI/g-POCN and g-OCN supports, which provide stability and improve the properties of biomimetically synthesized PANI. This work reveals the biomimetic synthesis of PANI, assisted by hematin supported by modified carbon nitrides, as a promising strategy to produce nanostructured supercapacitors with high performance.

The present investigation involves the coordinative chain transfer polymerization (CCTP) of biobased terpenes in order to obtain sustainable polymers from myrcene (My) and farnesene (Fa), using the ternary Ziegler-Natta catalyst system comprising [NdV 3 ]/[Al( i -Bu) 2 H]/[Me 2 SiCl 2 ] and Al( i -Bu) 2 H, which acts as cocatalyst and chain transfer agent (CTA). The polymers were produced with a yield above 85% according to the monomeric consumption at the end of the reaction, and the kinetic examination revealed that the catalyst system proceeded with a reversible chain transfer mechanism in the presence of 15-30 equiv. of CTA. The resulting polyterpenes showed narrow molecular weight distributions (M w /M n = 1.4-2.5) and a high percent of 1,4- cis microstructure in the presence of 1 equiv . of Me 2 SiCl 2 , having control of the molecular weight distribution in Ziegler-Natta catalytic systems that maintain a high generation of 1,4- cis microstructure.

It has been two decades since biomimetic synthesis of conducting polymers were first reported, however, the systematic investigation of how catalysts influence the properties of the conducting polymers has not been reported yet. In this paper, we report a comparative study between peroxidase-like catalyst, dopants, and their effect on the properties of poly (3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPY), and polyaniline (PANI). We also investigate the EDOT-Pyrrole and EDOT-Aniline copolymerization by enzymomimetic synthesis using two catalysts (Ferrocene and Hematin). It was found that, chemically, there are no detectable effects, only having small contributions in molar ratios greater than 0.7-0.3. Spectroscopic data provide solid evidence concerning the effect in the variation of the molar fractions, finding that, as the molar fraction of EDOT decreases, changes associated with loss of the conjugation of the structure and the oxidation state of the chains were observed. The electrical conductivity was considerably modified depending on the type of catalyst. Hematin produces conductive homopolymers and copolymers when doped with p -toluene sulfonic acid (TSA), while ferrocene produces low conductive copolymers under the same conditions. The mole fraction affects conductivity significantly, showing that as the EDOT fraction decreases, the conductivity drops drastically for both EDOT-PY and EDOT-ANI copolymers. The type of dopant also notably affects conductivity; the best values were obtained by doping with TSA, while the lowest were obtained when doping with polystyrene sulfonate (PSS). We also draw a biomimetic route to tailor the fundamental properties of conducting homopolymers and copolymers for their design and scaled-up production, as they have recently been found to have use in a broad range of applications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Martínez-Cartagena, Bernal-Martínez, Banda-Villanueva, Magaña, Córdova, Ledezma-Pérez, Fernández-Tavizón and Díaz de León.)

The interest in the Coordinative Chain Transfer Polymerization (CCTP) of a family of naturally occurring hydrocarbon monomers, namely terpenes, for the production of high-performance rubbers is increasing year by year. In this work, the synthesis of poly(β-myrcene) via CCTP is introduced, using neodymium versatate (NdV 3 ), diisobutylaluminum hydrade (DIBAH) as the catalytic system and dimethyldichlorosilane (Me 2 SiCl 2 ) as the activator. A bimodal distribution in the GPC signal reveals the presence of two populations at low conversions, attributable to dormants (arising from reversible chain transfer reactions) and dead chains (arising from termination and irreversible chain transfer reactions); a unimodal distribution is generated at medium and high conversions, corresponding to the dominant species, the dormant chains. Additionally, a mathematical kinetic model was developed based on the Method of Moments to study a set of selected experiments: ([ β-myrcene ] 0 :[ NdV 3 ] 0 :[ DIBAH ] 0 :[ Me 2 SiCl 2 ] 0 = 660:1:2:1, 885:1:2:1, and 533:1:2:1). In order to estimate the kinetic rate constant of the systems, a minimization of the sum of squared errors (SSE) between the model predicted values and the experimental measurements was carried out, resulting in an excellent fit. A set of the Arrhenius parameters were estimated for the ratio [ β-myrcene ] 0 :[ NdV 3 ] 0 :[ DIBAH ] 0 :[ Me 2 SiCl 2 ] 0 = 660:1:2:1 in a temperature range between 50 to 70 °C. While the end-group functionality (EGF) was predominantly preserved as the ratio [ β-myrcene ] 0 :[ NdV 3 ] 0 was decreased, higher catalytic activity was obtained with a high ratio.

Packaging materials play an essential role in the preservation and marketing of food and other products. To improve their conservation capacity, antimicrobial agents that inhibit bacterial growth are used. Biopolymers such as starch and chitosan are a sustainable alternative for the generation of films for packaging that can also serve as a support for preservatives and antimicrobial agents. These substances can replace packaging of synthetic origin and maintain good functional properties to ensure the quality of food products. Films based on a mixture of corn starch and chitosan were developed by the casting method and the effect of incorporating cellulose nanocrystals (CNC) at different concentrations (0 to 10% w / w ) was studied. The effect of the incorporation of CNC on the rheological, mechanical, thermal and barrier properties, as well as the antimicrobial activity of nanocomposite films, was evaluated. A significant modification of the functional and antimicrobial properties of the starch-chitosan films was observed with an increase in the concentration of nanomaterials. The films with CNC in a range of 0.5 to 5% presented the best performance. In line with the physicochemical characteristics which are desired in antimicrobial materials, this study can serve as a guide for the development this type of packaging for food use.