pinecone/core-2020-05-10-deduplication huggingface dataset:
Extruded versus solvent cast blends of poly(vinyl alcohol-co-ethylene) and biopolymers isolated from municipal biowaste

Water-soluble biopolymers (SBO) were isolated from the alkaline hydrolysate of two materials sampled from an urban waste treatment plant; that is, an anaerobic fermentation digestate and a compost. The digestate biopolymers contained more lipophilic and aliphatic C, and less acidic functional groups than the compost biopolymers. The SBO were blended with poly (vinyl alcohol-co-ethylene), hereinafter EVOH. The blends were extruded and characterized by FTIR spectroscopy, size exclusion chromatography (SEC)– multi angle static light scattering (MALS) analysis, and for their thermal, rheological, and mechanical properties. The blends behavior depended on the type of SBO and its relative content. Evidence was obtained for a condensation reaction occurring between the EVOH and SBO. The best results were obtained with the blends containing up to 10% SBO isolated from the biowaste anaerobic digestate. Compared with the neat EVOH, these blends exhibited lower  melt viscosity and no significant or great difference in mechanical properties. The results on the extrudates, compared with those previously obtained on the same blends obtained by solvent casting, indicate that the blends properties depend strongly also on the processing technology
Effect of microcellular foaming on the fracture behavior of ABS polymer

In this work, the properties of microcellular ABS were studied. Foamed samples exhibited a solid skin/foamed core struc- ture, with some elongated cells in the flow direction, while spherical cells were mostly observed in the transversal direction. The flex- ural modulus, flexural strength, and fracture toughness K Ic decreased with the density. However, the crack tip opening displacement (CTOD) was found to increase with the foaming ratio. The evolution of the mechanical properties and fracture toughness was well described by prediction models considering the skin/core morphology of these microcellular materials. Foaming increased the aniso- tropic behavior of the material, due to the cell elongation caused by the fountain flow during injectionPeer ReviewedPostprint (author's final draft
Morphology and dynamical mechanical properties of poly ether ketone ketone (PEKK) with meta phenyl links

Poly ether ketone ketone (PEKK) with different proportion of meta phenyl links were investigated by combining differential scanning calorimetry and dynamic mechanical analysis. The influence of the Terephthalyl/Isophthalyl isomers (T/I) ratio on the vitreous phase is mild, the shift of the glass transition is limited to a few degrees and the vitreous G0 is only sensitive to the content of the crystalline phase. Contrarily, the increase of meta isomers is responsible for a significant decrease of the melting temperature (Tm) by 60 8C, which considerably facilitates processing. The modification of interchain interactions in the crystalline phase might be implied. A series of thermal protocols evidenced that the difference of crystallization behavior is also dependent upon the T/I isomer ratio. A time and temperature dependence of annealing on the double melting behavior of PEKK was observed. Regarding the mechanical behavior, the observed reinforcing effect due to the crystalline phase was more prominent in the rubbery state than in the glassy state
Effect of ionic liquids on the structural, thermal and in vitro degradation properties of poly(ε-caprolactone) synthesized in the presence of Candida antarctica lipase B

The study provides detailed information on the differences in the structural, thermal and degradation properties of poly(e-caprolactone) synthesized in two different ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6] and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [bmim][NTf2], regarding its further usage in the pharmaceutical field. The polymer structure confirms the presence of both linear polymer chains with end-functional hydroxyl groups allowing covalent coupling of the therapeutic agents, and cyclic macromolecules, both affecting the degree of crystallinity of polymer. The highest macrocyclic content (64%) after 7 days of polymerization at 80 8C was observed for [bmim][NTf2]. For [bmim][PF6], the macrocyclic content value was not dependent on the reaction time and remained at a similar level (10–14% at 80 8C). The results of degradation test revealed that hydrolytic degradation of ester bonds is more pronounced for PCLs synthesized in [bmim][NTf2], due to their lower degree of crystallinity compared with PCLs obtained in [bmim][PF6]. A high purity, low polydispersity index of the obtained polymers and high yield of the process (ca., 90%) indicate that ionic liquids seem to be promising solvents for the synthesis of biomedical polymers
Influence of the notch-sharpening technique on styrene-acrylonitrile fracture behavior

The Centre Catala del Plastic and Universidad Rey Juan Carlos laboratories joined forces to investigate the effect of the notch-sharpening technique on the fracture parameters of styrene-acrylonitrile. Contact notch-sharpening techniques, such as razor tapping, razor sliding, and razor broaching, and a noncontact procedure, femtolaser, were analyzed. The fracture values of the samples with notches sharpened via contact techniques were divided into two groups: one with pop-in and the other with no pop-in in the load-displacement records; this resulted in the lowest and highest fracture toughnesses, respectively. The fracture parameters of the specimens with notches sharpened via a femtolaser were between those of the samples with notches sharpened via contact procedures in which pop-in occurred and those in which it did not. To explain these results, the crack front of the nontested specimens after sharpening was investigated in depth, we identified the type of damage and measured its size and the crack tip radii. The morphology of the crack front was related to the fractographic study.Postprint (author's final draft
Improvement of the impact strength of ethylene-propylene random copolymers by nucleation

Five ethylene-propylene random copolymers were nucleated with two soluble nucleating agents. Ethylene content changed between 1.7 and 5.3 wt %, while nucleating agent content was adjusted according to the solubility of the additive. It changed from 0 to 5000 ppm for the sorbitol (1,2,3-tridesoxy-4,6:5,7-bis-O-[(4-propylphenyl) methylene]-nonitol) and from 0 to 500 ppm for the trisamide compound (1,3,5-benzene-trisamide) used. Crystalline structure was analyzed in detail by various methods (DSC, XRD, and SEM). Mechanical properties were characterized by tensile and instrumented impact measurements. The results showed that most properties changed moderately upon nucleation, but impact resistance increased considerably. Spherulitic structure was not detected, but instead in the presence of the soluble nucleating agents used a microcrystalline structure formed. The large increase of impact resistance could not be related directly to changes in crystalline morphology. On the other hand, local rearrangement of morphology was detected by XRD and SEM analysis including an increase of lamella thickness, crystal orientation, and the formation of shish-kebab structures in the core of the injection molded specimens. A small increase in the γ-phase content of PP was also observed. These changes increased crack propagation energy considerably leading to the large improvement observed in impact resistance. Although the phenomenon could be related to ethylene content, differences in molecular weight also helped to explain the changes observed
Influence of the environment during a photodegradation of multilayer films

The influence of different stratosphere parameters on the degradation of a multilayer film was investigated. The selected multilayer was a three polymeric layers film, a polyamide 6 film inserted between two poly(ethylene terephthalate) (PET) films. Samples were exposed for several ageing under ultraviolet radiations (filtered at 270 nm), varying the atmosphere at 55 mbar pressure (atm, atm + ozone, N2, and T = −55 °C or +23 °C). Evolution of it mechanical properties defined by uniaxial tractions, thermo-optical properties defined by spectrophotometry UV–vis-NIR, chemical properties defined by FTIR-ATR, and thermal and dielectric properties defined, respectively, by differential scanning calorimetry (DSC) and dynamical dielectric spectroscopy (DDS), were investigated. Our results showed that UV irradiation causes multilayer films degradations, that is, principally decrease of UV transmittance and stress and strain at break (−50%). An increase of the ageing temperature causes an acceleration of these degradations. Degradations principally occur on the PET side of the multilayer exposed to UV radiation. Moreover, the DDS analysis shows a plasticization effect of the primary mode in the polyamide 6 due to photo-oxidation. Oxygen diffusion is the principal element for this plasticization, indeed it not occurs in a nonoxidative environment (nitrogen), or at low ageing temperature (−55 °C)
Comparative study of visible light polymerized gelatin hydrogels for 3D culture of hepatic progenitor cells

Photopolymerization techniques have been widely used to create hydrogels for biomedical applications. Visible light-based photopolymerizations are commonly initiated by type II (i.e., noncleavage-type) photoinitiator in conjunction with a coinitiator. On the other hand, type I photoinitiators (i.e., cleavage type) are rarely compatible with visible light-based initiation due to their limited molar absorbability in the visible light wavelengths. Here, we report visible light initiated orthogonal photoclick crosslinking to fabricate gelatin-norbornene and poly(ethylene glycol)-tetra-thiol hydrogels using either cleavage-type (i.e., lithium acylphosphinate, LAP) or noncleavage-type photoinitiator (i.e., eosin-Y, EY) without the use of a coinitiator. Regardless of the initiator type, the step-growth gelatin-PEG hybrid hydrogels crosslinked and degraded similarly. While both systems exhibited similar cytocompatibility for hepatic progenitor HepaRG cells, gelation initiated by noncleavage-type initiator EY afforded slightly higher degree of hepatic gene expression
Optimization of thermopressing conditions for the production of binderless boards from a coriander twin-screw extrusion cake

A deoiled press cake resulting from twin-screw extrusion of coriander fruits was used as a raw material for the production of self-bonded boards. The operating parameters for thermopressing were varied and include the applied pressure (19.6–39.2 MPa), molding time (60–300 s), and molding temperature (155–205 °C). The optimized process conditions (21.6 MPa, 300 s, 205 °C) resulted in a board with a density of 1323 kg/m3, a flexural strength of 23 MPa, a modulus of elasticity of 4.4 GPa, and a thickness swelling of 31%. The thickness swelling was effectively reduced to 20% through the application of a heat treatment at 200 °C after thermopressing. A variation of the moisture content of the press cake between 3 and 8% showed that increased moisture contents do not lead to improved mechanical properties of the resulting board and further induce internal fracturing of the board during thermopressing. The manufactured binderless boards may act as environmentally friendly alternatives to commercial wood-based boards such as oriented strand board and particleboard
Role of bismuth oxide as a reinforcer on gamma shielding ability of unsaturated polyester based polymer composites

Unsaturated Polyester resin is reinforced with Bi2O3 up to 60 filler weight. The effect of bismuth oxide on gamma shielding ability of the composites is studied in terms of attenuation parameters using Ba-133, Cs-137, and Co-60 gamma ray sources. The results reveal that, the shielding property of the composite material increases with increase in the filler concentration and decreases with energy. The HVL, TVL, and relaxation length of the composites are found to decrease with increase in the filler concentration. It is found that, the shielding ability of 60 filled polymer composite is comparable to that of barite at low energy. The above polymer composite performs well at all energies and can act as an excellent gamma radiation shield for low energies and also proved to be light weight when compared to the conventional shielding materials. Thus, the gamma shielding ability of the UP resin is enhanced due to the addition of Bi2O3. Â© 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44657. Â© 2016 Wiley Periodicals, Inc
Experimental study of the miscibility of ABS/PC polymer blends and investigation of the processing effect

In the challenging prospect of developing new materials by mixing different polymers to reach a synergetic performance, the present research focuses on the study of the miscibility of two polymers: The acrylonitrile butadiene styrene (ABS) composed of a dispersed elastomeric (polybutadiene rubber) polymer embedded in a SAN thermoplastic matrix, and the polycarbonate (PC). It shall be noted that obtaining miscible polymer blends is often a difficult task because of the large size of their molecular chains and the high interfacial tension between the polymer phases. Until now, the most numerous researches developed in this field involve polymer blends obtained by compatibilization techniques in order to improve the interfacial adhesion between initial polymers. The aim of this work is to study the miscibility between ABS and PC. First, two different methods were used to mix the polymers: the twin-screw extrusion and the dissolution in a common solvent tetrahydrofuran (THF). Then, physicochemical, microscopic observation and rheological characterization were performed on samples of mixtures obtained by both extrusion processing and dissolution method. The measurement of glassy transition temperature (Tg) by differential scanning calorimetry measurements (DSC) and dynamical mechanical thermal analysis (DMTA) have shown a partial miscibility between the two polymers
Orientational behaviors of silk fibroin hydrogels

In this study, a novel shear-induced silk fibroin hydrogel with three-dimensional (3D) anisotropic and oriented gel skeleton/network morphology is presented. Amphipathic anionic and nontoxic sodium surfactin is blended with the silk fibroin to decrease its gelation time during the mechanical shearing process. The fibroin/surfactin blended solutions undergo a facial shearingÂ process to accomplish a solâ  gel transition within one hour. The dynamic solâ  gel transition kinetic analysis, gel skeleton/network morphology,
and mechanical property measurements are determined in order to visualize the fibroin/surfactin solâ  gel transition duringÂ the shearing process and its resulting hydrogel. The results demonstrate that there is significant b-sheet assembly from random coilÂ conformations in the fibroin/surfactin blended system during the facile shearing process. The silk fibroin b-sheets further transformÂ into a fibrous large-scale aggregation with orientational and parallel arrangements to the shearing direction. The shear-induced fibroin/
surfactin hydrogel exhibits notable anisotropic and oriented 3D skeleton/network morphology and a significant mechanical compressiveÂ strength in proportion to the shearing stress, compared with the control fibroin/surfactin hydrogel undergoing no shearingÂ process. Due to its oriented gel skeleton/network structure and significantly enhanced mechanical properties, the shear-induced fibroin/Â surfactin gel may be suitable as a biomaterial in 3D oriented tissue regeneration, including for nerves, the cultivation of bone cells,Â and the repair of defects in muscle and ligament tissues.The work is supported by National Natural Science Foundation of
China (Grant No. 51373114), PAPD and College Nature Science
Research Project of Jiangsu Province, China (Grant No.
15KJA540001). S. C. Kundu holds ERA Chair Full Professor of
European Commission Programme (RoReCaST) at 3Bs Research
Group, University of Minho, Portugal.info:eu-repo/semantics/publishedVersio
Adhesion Control of Interface between Cellulose and Polypropylene by Vapor-Phase Assisted Surface Copolymerization

In order to achieve the effective interface bonding between biomass microfiller and commodity plastics, consecutive copolymerization of hydrophilic acrylic acid (AA) and hydrophobic butyl acrylate (BA) using vapor-phase assisted surface polymerization (VASP) technology was applied to prepare micro composites consisting of cellulose micro crystal (CμC) and polypropylene (PP). After the copolymerization by VASP, CμC surfaces were covered by accumulated polymers: P(AA-co-BA) including block-type copolymer and homopolymers of 6.2-25.3 wt% versus CμC. Although structures of the products were unspecified, it was expected to be mixtures of block copolymers and homopolymers. Subsequently prepared P(AA-co-BA) on CμC/PP (5/95 wt/wt) composites expressed a superior mechanical toughness, which had increased threefold when compared to intact CμC/PP composite. This increase in toughness was mainly based on an increase in elongation rate, reflecting improvement of the adhesion strength at the interface between CμC surface and PP. The trace amounts: 0.31 wt% of accumulated P(AA-co-BA) on CμC surface must function as an effective adhesive/compatibilizer at the interface
Polymeric seal degradation in nuclear power plants: Determination of physical and mechanical properties

o assess the suitability of different materials as polymeric seals in the Nuclear Industry three commercial samples of nitrile rubber at grades BA40, BA50, and BA60 have been tested. Differential scanning calorimetry was used to find the glass transition temperature (Tg) and a Lloyds Texture Analyser 500 (TA500) was used to find the ratio of energy returned during relaxation against energy applied during compression. The mechanical properties determined from these experiments were then compared against the materials infrared spectra to infer structural characteristics. These were in turn cross-analyzed against the materials ability to swell in a liquid solvent and absorption behavior in a gaseous solvent. From this information, a statement could be made about each material's capacity to perform as a seal. It was thus found that the high energy retention and low absorption characteristics of BA40 made this material the best choice out of those studied for use as a polymeric seal in the nuclear industry
Measurement of thermal conductivity of epoxy resins during cure

This work reports the development of a methodology for the measurement of thermal conductivity of thermosetting polymers during their cure. The study addresses the reliability and robustness of the method through FEA modeling and testing using a noncuring material with known thermal conductivity. The thermal conductivity and its evolution during the cure has been measured for three widely used aerospace epoxy resins, namely, RTM6, 890RTM, and the XU3508/XB3473 system as function of cure temperature. A constitutive model expressing the dependence of thermal conductivity on the degree of cure and temperature has been established. The device developed here can measure thermal conductivity of epoxy resin with accuracy up to 3%
Implications of Australia's population policy for future greenhouse gas emissions targets

Version of Record online: 11 JUN 2016Australia's high per capita emissions rates makes it is a major emitter of anthropogenic greenhouse gases, but its low intrinsic growth rate means that future increases in population size will be dictated by net overseas immigration. We constructed matrix models and projected the population to 2100 under six different immigration scenarios. A constant 1 per cent proportional immigration scenario would result in 53 million people by 2100, producing 30.7 Gt CO2-e over that interval. Zero net immigration would achieve approximate population stability by mid-century and produce 24.1 Gt CO2-e. Achieving a 27 per cent reduction in annual emissions by 2030 would require a 1.5- to 2.0-fold reduction in per-capita emissions; an 80 per cent reduction by 2050 would require a 5.8- to 10.2-fold reduction. Australia's capacity to limit its future emissions will therefore depend primarily on a massive technological transformation of its energy sector, but business-as-usual immigration rates will make achieving meaningful mid-century targets more difficult.Corey J. A. Bradshaw and Barry W. Broo
Growth in densely populated Asia: implications for primary product exporters

Economic growth and integration in Asia is rapidly increasing the global economic importance of the region. To the extent that this growth continues and is strongest in natural resource-poor Asian economies, it will add to global demand for imports of primary products, to the benefit of (especially nearby) resource-abundant countries. How will global production, consumption and trade patterns change by 2030 in the course of such economic developments and structural changes? We address this question using the GTAP model and Version 8.1 of the 2007 GTAP database, together with supplementary data from a range of sources, to support projections of the global economy from 2007 to 2030 under various scenarios. Factor endowments and real gross domestic product are assumed to grow at exogenous rates, and trade-related policies are kept unchanged to generate a core baseline, which is compared with an alternative slower growth scenario. We also consider the impact of several policy changes aimed at increasing China's agricultural self-sufficiency relative to the 2030 baseline. Policy implications for countries of the Asia-Pacific region are drawn out in the final section.Kym Anderson and Anna Strut
Growth in densely populated Asia: implications for primary product exporters

Economic growth and integration in Asia is rapidly increasing the global economic importance of the region. To the extent that this growth continues and is strongest in natural resource-poor Asian economies, it will add to global demand for imports of primary products, to the benefit of (especially nearby) resource-abundant countries. How will global production, consumption and trade patterns change by 2030 in the course of such economic developments and structural changes? We address this question using the GTAP model and Version 8.1 of the 2007 GTAP database, together with supplementary data from a range of sources, to support projections of the global economy from 2007 to 2030 under various scenarios. Factor endowments and real gross domestic product are assumed to grow at exogenous rates, and trade-related policies are kept unchanged to generate a core baseline, which is compared with an alternative slower growth scenario. We also consider the impact of several policy changes aimed at increasing China's agricultural self-sufficiency relative to the 2030 baseline. Policy implications for countries of the Asia-Pacific region are drawn out in the final section
The "Paradox of Diversity": economic evidence from US cities 1980-2010

We evaluate the economic significance of linguistic barriers to communication in 226 US cities from 1980 to 2010.  We address the question: to what extent to linguistic across social groups inhibit the benefits of knowledge exchange?  The empirical results show that linguistic, racial and composite diversity increase the average income of working age population in American cities.  This positive effect of diversity, however, diminishes the higher is the proportion of foreign-born population who lack English fluency.  We call this the "paradox of diversity".  Overall, our findings provide important policy insights about how social diversity may enhance economic performance within cities