pinecone/core-2020-05-10-deduplication huggingface dataset:
Poly(butylene succinate) ionomers and their use as compatibilizers in nanocomposites

A series of low-molecular-weight poly(butylene succinate-co-glutarate-co-2-trimethylammonium chloride glutarate) terpolyester ionomers containing 35% mol of total glutarate units but varying in the content of charged units were synthesized by polycondensation at mild temperatures using a scandium catalyst. The terpolyester ionomers started to decompose at the temperatures of >175°C and all of them were semicrystalline and have glass transition temperature similar to poly(butylene succinate) (PBS). These terpolyesters were used to compatibilize the nanocomposites made of PBS-cloisite (CL) prepared by melt extrusion. X-ray diffraction revealed that an intercalated structure was present in these nanocomposites. The thermal properties of the three-component mixtures did not differ substantially from those of PBS–CL but the mechanical properties were significantly improved by the addition of the ionomer, in particular tenacity. The beneficial effect afforded by the terpolyester ionomer was attributed to its ability for strengthening the binding between the PBS and the nanoclay.A series of low-molecular-weight poly(butylene succinate-co-glutarate-co-2-trimethylammonium chloride glutarate) terpolyester ionomers containing 35% mol of total glutarate units but varying in the content of charged units were synthesized by polycondensation at mild temperatures using a scandium catalyst. The terpolyester ionomers started to decompose at the temperatures of >175°C and all of them were semicrystalline and have glass transition temperature similar to poly(butylene succinate) (PBS). These terpolyesters were used to compatibilize the nanocomposites made of PBS-cloisite (CL) prepared by melt extrusion. X-ray diffraction revealed that an intercalated structure was present in these nanocomposites. The thermal properties of the three-component mixtures did not differ substantially from those of PBS–CL but the mechanical properties were significantly improved by the addition of the ionomer, in particular tenacity. The beneficial effect afforded by the terpolyester ionomer was attributed to its ability for strengthening the binding between the PBS and the nanoclay.Peer ReviewedPostprint (author's final draft
Study of partial shape memory effect of polymers by multicycle tests

In this work, an experimental investigation on a partial shape memory polymer (PSMP) which is transformed into shape memory material is presented. Multicycle shape memory tests are performed on thermoplastic polyurethane (TPU) at 70°C. At the end of each cycle, the capacity of the shape memory material increases. At the end of the first cycle, the recovery rate of TPU is only 67%; this partial shape memory effect (PSME) has been improved by successive cycles of shape memory tests. After the fourth cycle, it becomes nearly 100% shape memory material. The results of the fifth and sixth cycles confirm this modification. These original results indicate that a polymer with partial shape memory may be transformed into an SMP without any chemical modification. This increase of SME could be related to the creation of residual stresses during the tensile tests. The residual stresses are the origin of the driving force responsible for SME
Effects of surface-functionalized aluminum nitride on thermal, electrical, and mechanical behaviors of polyarylene ether nitrile-based composites

This is the peer reviewed version of the following article: CHEN, Y. ... et al, 2016. Effects of surface-functionalized aluminum nitride on thermal, electrical, and mechanical behaviors of polyarylene ether nitrile-based composites. Polymer Composites, 37 (10), pp. 3033 - 3041, which has been published in final form at, http://dx.doi.org/10.1002/pc.23500. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingAluminum nitride (AlN) with high thermal conductivity was blended in polyarylene ether nitrile (PEN) to obtain a composite system. A ball milling process could provide AlN particles of smaller size with higher surface silylation for homogeneous particle distribution in polymeric matrix. Thermal, electrical, and mechanical behaviors of the produced composites were characterized to investigate the effects of particles on the performance of PEN-based composites with functionalized AlN. The composite exhibited thermal conductivity of 0.779 W m−1 K−1, a dielectric constant of 7.7, dielectric loss of 0.032, electrical resistivity of 1.39 GΩ.cm, and break strength of 36 N when the fraction of functionalized AlN increased to 42.3 vol%. A fitted equation based on the improved Russell's model could effectively predict a trend for thermal conductivity of the composite systems with consideration of interfacial resistance between AlN and surrounding PEN
A modified fiber-reinforced plastics concrete interface bond-slip law for shear-strengthened RC elements under cyclic loading

The objective of this article is to realistically analyze fiber-reinforced plastics (FRP) retrofitted reinforced concrete structures under cyclic loading taking into account FRP–concrete bond-slip law with cyclic bond degradation. In literature, even though numerous studies have been conducted in FRP–concrete interface bond-slip modeling under cyclic loads, a small number of them consider the influence of cyclic degradation on FRP–concrete interface bond behavior. Within this framework, the bond-slip law for carbon fiber-reinforced plastics–concrete interface is revised by utilizing Harajli's and Ko-Sato's approaches. The procedure is distinct from others because it develops existing deficiencies of these approaches, whereas a more reliable modeling process is proposed for use in practice. Conventional bond-slip law of Lu et al. is compared with this interface relationship stated in this investigation and the difference is clearly shown in terms of structural parameters. Experimental tests are conducted at the same time for verification. It is proved that cyclic bond degradation affects the interface behavior; thus, the structural response cannot be omitted in structural evaluations. Structural performance measures are obtained in good agreement for each level of cycles. The technique proposed clearly exhibits structural response difference between monotonic and cyclic loadings while good agreement is reached with experimental results. POLYM. COMPOS., 37:3373–3383, 2016. © 2015 Society of Plastics Engineers.Scientific and Technological Research Council of Turkey (111M559
PREDICTION OF TRANSPORT VEHICLES’ DURABILITY WITH CONSIDERATION OF CORROSIVE SURFACE CRACKS PROPAGATION IN STRUCTURAL ELEMENTS

Support frameworks of transport vehicles operate under varying
terrain conditions under the influence of extreme climate and corrosive
environments. When transporting cargo, dust is deposited on the surface of metal
structures. The combination of dust and moisture creates an aggressive
environment resulting in intense corrosion damage. The damage is caused by the
defects of corrosion pitting, which occur on the surface and transform into
corrosion cracks. Based on energy approaches, with the application of wellknown results for the mathematical description of electrochemical reactions and
the principles of fragile fracture mechanics, an analytical model of durability is
proposed for the first time. The model determines the residual life of maximum
loaded elements of undercarriages with surface cracks under the action of
dynamic loads and corrosive environments. For this case, a set of mathematical
relations in the form of a non-linear differential equation was developed, as well as the initial and final conditions for determining the life of vehicles’ structural
elements with corrosive surface cracks. The analytical model implementation is
proven by solving the problem of determining the residual life of a vehicle’s
element, i.e., a steel plate, weakened by a semi-elliptical surface crack, which is
under the action of dynamic loads in a 3% sodium chloride solution. The
insignificant increase in the crack’s initial size is proven to greatly reduce the
period of its subcritical growth. The developed model was applied to define the
residual life of thin-walled elements of structures with surface cracks
A novel conducting nanocomposite obtained by p-anisidine and aniline with titanium(IV) oxide nanoparticles: Synthesis, Characterization, and Electrochemical properties

Nanocomposites were successfully synthesized by the oxidative polymerization of p-anisidine and/or aniline monomers (at initial “p-anisidine:aniline” mole ratios of “100 : 0,” 50 : 50,” and “0 : 100”) with titanium(IV) oxide nanoparticles, in the presence of hydrochloric acid as a dopant with ammonium persulfate as an oxidant. The morphological, structural, conductivity, and electrochemical properties of the synthesized nanocomposites were studied using Transmission Electron Microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and UV–vis spectroscopies. The presence of polymer on TiO2 nanoparticles in samples nanocomposites was confirmed by the Transmission Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy. The thermal stability of samples nanocomposites were evaluated using the Thermogravimetric Analysis. Electrical conductivity of nanocomposites obtained is in the range of 0.08 − 0.91 S cm−1. The electrochemical behavior of the polymers extracted from the nanocomposites has been analyzed by cyclic voltammetry. Good electrochemical response has been observed for polymer films; the observed redox processes indicate that the polymerization on TiO2 nanoparticles produces electroactive polymers. These composite microspheres can potentially be used in commercial applications as fillers for antistatic and anticorrosion coatings.National Assessment and Planning Committee of the University Research (CNEPRU); contract grant number: E-03720130015; contract grant sponsor: MINECO; contract grant number: MAT2013-42007-P; contract grant sponsor: Generalitat Valenciana; contract grant number: PROMETEO2013/038; contract grant sponsor: Directorate General of Scientific Research and Technological Development (DGRSDT) of Algeria
Stochastic simulation of the influence of fibre path variability on the formation of residual stress and shape distortion

A stochastic cure simulation approach is developed and implemented to investigate the influence of fibre misalignment on cure. Image analysis is used to characterize fiber misalignment in a carbon non-crimp fabric. It is found that variability in tow orientation is significant with a standard deviation of 1.2°. The autocorrelation structure is modeled using the Ornstein-Uhlenbeck sheet and the stochastic problem is addressed by coupling a finite element model of cure with a Monte Carlo scheme. Simulation of the cure of an angle shaped carbon fiber-epoxy component shows that fiber misalignment can cause considerable variability in the process outcome with a coefficient of variation in maximum residual stress up to approximately 2% (standard deviation of 1 MPa) and qualitative and quantitative variations in final distortion of the cured part with the standard deviation in twist and corner angle reaching values of 0.4° and 0.05° respectively. POLYM. COMPOS., 2015. © 2015 The Authors Polymer Composites published by Wiley Periodicals, Inc. on behalf of Society of Plastics Engineer
Effects of thermal recycling temperatures on the reinforcement potential of glass fibers

In the present work the reinforcement potential of thermally recycled glass fibers in injection molded Polypropylene (PP) composites was investigated. Microbond tests showed that fiber sizing lost its compatibility to the PP matrix after exposure to temperatures of 250 °C in air. The drop of the adhesion between fibers and PP was mirrored by a large reduction of the tensile strength of the injection molded PP composites. In inert atmosphere the degradation of the fiber sizing and the reduction of the IFSS were less rapid than in air but no significant difference was observed above 400 °C. It was concluded that thermally recycled glass fibers will require a post-treatment to act as an effective reinforcement in injection molded PP composites even if the thermal recycling was performed in an inert atmosphere. The post-treatment will need to improve the compatibility of the fibers to the polymer matrix and the fiber strength
Effect of multi-layered nanostructures on the physico-mechanical properties of ethylene vinyl acetate based hybrid nanocomposites.

Exfoliated graphene oxide (GO) and Mg-Al-layered double hydroxides (LDHs) nanostructures (LDHs@GO)-filled ethylene vinyl acetate (EVA)-based hybrid nanocomposites were prepared by solution reflux technique followed by injection molding. The physico-mechanical (including morphological, thermal, and mechanical) properties of LDHs@GO-based-layered nanostructures and EVA/LDHs@GO (0-1 wt%)-based hybrid nanocomposites were analyzed by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, wide and low angle X-ray diffraction spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and mechanical (tensile and elongation at break) testing. The morphological studies revealed that LDHs sheets were homogeneously inserted in between GO sheets, while LDHs@GO-based-layered nanostructures were found to be easily exfoliated in EVA/LDHs@GO hybrid nanocomposites up to 0.7 wt% loading after which agglomeration occurred. The thermal stability of the hybrid nanocomposites was found to be improved at highest LDHs@GO loading of 0.7 wt%. Mechanical properties (tensile strength and elongation at break) of the hybrid nanocomposites were observed to be enhanced by 70 and 80%, respectively, at LDHs@GO loading of 0.7 wt% and highest values of mechanical properties were obtained. Though, the morphological, thermal, and mechanical properties of the composites were improved, the FTIR analysis did not reveal any chemical interaction between EVA and the LDHs@GO-based-layered nanostructures. From the overall results, it is obvious that a significant synergism was observed in terms of morphological, thermal, and mechanical properties of EVA/LDHs@GO hybrid nanocomposites with optimum (less than 1 wt%) loading of LDHs@GO-based-layered nanostructures.University Grant Commission (UGC), New Delhi, Government of India - Rajiv Gandhi National Junior Research Fellowship [F1-17.1/2014-15/RGNF-2014-15-SC-MAH-58232/(SA-III/Website)] ; Department of Science and Technology (DST-UKIERI), New Delhi, India [File No: DST/INT, UK/P-108/2014]
Phytochemical fingerprinting of vegetable Brassica oleracea and Brassica napus by simultaneous identification of glucosinolates and phenolics

[Introduction] Brassica vegetables have been related to the prevention of cancer and degenerative diseases, owing to their glucosinolate and phenolic content.[Objective] Identiﬁcation of glucosinolates, ﬂavonoids and hydroxycinnamic acids in representative varieties of kale, cabbage and leaf rape.[Methodology] One local variety of each crop was evaluated in this study using a multi-purpose chromatographic method that simultaneously separates glucosinolates and phenolics. Chromatograms were recorded at 330 nm for ﬂavonoid glycosides and acylated derivatives and 227 nm for glucosinolates.[Results] Eight glucosinolates were identiﬁed in kale and cabbage, which exhibited the same glucosinolate proﬁle, and 11 glucosinolates were identiﬁed in leaf rape. Furthermore, 20 ﬂavonoids and 10 hydroxycinnamic acids were detected in kale and cabbage, while 17 ﬂavonoids and eight hydroxycinnamic acids were found in leaf rape.[Conclusions] This study has provided a deeper and comprehensive identiﬁcation of health-promoting compounds in kale, cabbage and leaf rape, thus showing that they are a good source of glucosinolates and phenolic antioxidants. Copyright © 2011 John Wiley & Sons, Ltd.This research was supported by the National Plan for Research and Development (AGL2009-09922) and the Excma. Diputación Provincial de Pontevedra.N
Comparing the composition and bioactivity of Crataegus monogyna flowers and fruits used in folk medicine.

Introduction- Studying local plant foods is of particular interest as they often contain high amounts of bioactive compounds. Furthermore, their nutritional and medicinal impact must be documented and supported with scientific studies. Crataegus monogyna is an example of “functional food” traditionally used all over South European countries. 
Objective- A complete chemical and bioactive characterization of flower buds, flowers, unripe, ripened and over ripened fruits was performed. 
Methodology- Chemical characterization included determination of proteins, fats, ash, and carbohydrates, particularly sugars by HPLC-RI, fatty acids by GC-FID, tocopherols by HPLC-fluorescence, phenolics, flavonoids, β-carotene and ascorbic acid, by spectrophotometric techniques. Bioactivity was evaluated through screening of antioxidant properties: radical scavenging effects, reducing power, and inhibition of lipid peroxidation.
Results- Flowers revealed the highest tocopherols and ascorbic acid contents, as also the best n-6/n-3 fatty acids ratio. Over ripened fruits showed the highest levels of carbohydrates, sugars and SFA. Unripe fruits presented the highest PUFA contents with the best PUFA/SFA ratio, as also the highest levels of phenolics and the most promising antioxidant properties (EC50 < 20.83 µg/ml; even better than trolox).
Conclusion- This study shows the potential of different parts of Crataegus monogyna as sources of several compounds, including nutrients and nutraceuticals. Moreover, it supports the documented nutritional and medicinal impact of this species
Rapid profiling of intact glucosinolates in Arabidopsis leaves by UHPLC-QTOFMS using a charged surface hybrid column.

INTRODUCTION: The analysis of glucosinolates (GS) is traditionally performed by reverse-phase liquid chromatography coupled to ultraviolet detection after a time-consuming desulphation step, which is required for increased retention. Simpler and more efficient alternative methods that can shorten both sample preparation and analysis are much needed.
OBJECTIVE: To evaluate the feasibility of using ultrahigh-pressure liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOFMS) for the rapid profiling of intact GS.
METHODOLOGY: A simple and short extraction of GS from Arabidopsis thaliana leaves was developed. Four sub-2 µm reverse-phase columns were tested for the rapid separation of these polar compounds using formic acid as the chromatographic additive. High-resolution QTOFMS was used to detect and identify GS.
RESULTS: A novel charged surface hybrid (CSH) column was found to provide excellent retention and separation of GS within a total running time of 11 min. Twenty-one GS could be identified based on their accurate mass as well as isotopic and fragmentation patterns. The method was applied to determine the changes in GS content that occur after herbivory in Arabidopsis. In addition, we evaluated its applicability to the profiling of other Brassicaceae species.
CONCLUSION: The method developed can profile the full range of GS, including the most polar ones, in a shorter time than previous methods, and is highly compatible with mass spectrometric detection
Secondary Metabolites from the Phloem of Piper solmsianum (Piperaceae) in the Honeydew of Edessa meditabunda

Introduction The phytochemistry of species of the genus Piper has been studied extensively, including Piper solmsianum. However, no studies have addressed the phytochemistry of the sap content of Piper species. Objective To evaluate the transferring of secondary compounds from the saps of P. solmsianum to the honeydew of Edessa meditabunda. Methodology The honeydew of E. meditabunda and saps of P. solmsianum were analysed by GC-MS, H-1-NMR and LC-MS. Results The lignan (-)-grandisin and the phenylpropanoid (E)-isoelemicin were detected in both saps of P. solmsianum and honeydew of E. meditabunda. Conclusion Analysis of honeydew secreted by the sap-sucking insect E. meditabunda indicated that (-)-grandisin and (E)-isoelemicin are absorbed from the phloem of Piper solmsianum. Copyright (c) 2012 John Wiley & Sons, Ltd
Phenolic Profiling of Portuguese Propolis by LC-MS Spectrometry: Uncommon Propolis Rich in Flavonoid Glycosides

Introduction Propolis is a chemically complex resinous substance collected by honeybees (Apis mellifera) from tree buds, comprising plant exudates, secreted substances from bee metabolism, pollen and waxes. Its chemical composition depends strongly on the plant sources available around the beehive, which have a direct impact in the quality and bioactivity of the propolis. Being as Portugal is a country of botanical diversity, the phenolic characterisation of propolis from the different regions is a priority. Objective Extensive characterisation of the phenolic composition of Portuguese propolis from different continental regions and islands. Method Forty propolis ethanolic extracts were analysed extensively by liquid chromatography with diode-array detection coupled to electrospray ionisation tandem mass spectrometry (LC-DAD-ESI-MSn). Results Seventy-six polyphenols were detected in the samples and two groups of propolis were established: the common temperate propolis, which contained the typical poplar phenolic compounds such as flavonoids and their methylated/esterified forms, phenylpropanoid acids and their esters, and an uncommon propolis type with an unusual composition in quercetin and kaempferol glycosides - some of them never described in propolis. Conclusion The method allowed the establishment of the phenolic profile of Portuguese propolis from different geographical locations, and the possibility to use some phenolic compounds, such as kaempferol-dimethylether, as geographical markers. Data suggest that other botanical species in addition to poplar trees can be important sources of resins for Portuguese propolis. Copyright (c) 2012 John Wiley & Sons, Ltd