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A Pizzi - One of the best experts on this subject based on the ideXlab platform.
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Hydroxypropyl tannin from Pinus pinaster bark as polyol source in urethane chemistry
European Polymer Journal, 2015Co-Authors: D E Garcia, A Pizzi, Wolfgang G Glasser, S. Paczkowski, M P LaborieAbstract:Novel thermosetting polyphenol-based polyurethane (PU) films were prepared using condensed tannin (CTs) and hydroxypropyl tannin derivatives (HPTs) from Pinus pinaster bark and diisocyanates. Four HPTs with a degree of substitution (DS) rising stepwise from 1 to 4 were crosslinked with either an aromatic (polymeric methylene diphenyl diisocyanate (pMDI)) or an aliphatic isocyanate (hexamethylene diisocyanate (HDI)). Chemical structure, moisture sorption, thermal, and morphological properties of the films were studied. Properties varies with NCO:OH ratio (0.5-4.0), DS, diisocyanate type, and cross-link density (CD). Partial tannin hydroxypropylation (DS 2, 3) based/films showed a flexible-type character in term of Young's modulus, elongation and tensile strain. Significant relationships were established between CD and physicochemical properties. HPTs constitute suitable macro building-block polyols for urethane chemistry.
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Microwave assisted extraction of maritime pine (Pinus pinaster) bark: Impact of particle size and characterization
Industrial Crops and Products, 2015Co-Authors: Lucie Chupin, A Pizzi, S. L. Maunu, Stephanie Reynaud, Bertrand Charrier, Fatima Charrier-el BouhtouryAbstract:The effect of particle size on the extraction of tannins by microwave assisted extraction (MAE) was studied for the first time to our knowledge. Maritime pine (Pinus pinaster) bark from the South West of France was sieved into five ranges of particle size before extraction was carried out in an ethanol-water solution. For each extraction, the extraction yield, the total polyphenolic content, the condensed tannins content, and the sugar content were quantified. The extracts were characterized by their reactivity to formaldehyde, Fourier transformed infrared spectroscopy (FTIR), H-1 NMR, and heteronuclear single correlation spectroscopy-2D NMR (HSQC 2D NMR). The MAE was also compared to a hot water based extraction. The effect of the particle size on the extraction efficiency was studied. The HSQC 2D NMR revealed that (epi) catechin, epicatechin gallate, epigallocatechine, and epigallocatechine gallate were obtained. Higher amounts of condensed tannins, sugars, and simple flavonoids were extracted by MAE extraction.
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Pinus pinaster tannin furanic foams part ii physical properties
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, Alain CelzardAbstract:Foams with procyanidin-type tannins have been developed recently, more particularly with Pinus pinaster tannins. Mechanical properties in compression were tested. Thus, different thermal conductivity prediction models were compared with the experimental results. It was found that Glicksman model is the most suitable to predict radiative conductivity. The structure and cells size was determined by scanning electron microscopy. This paper gives for the first time physical properties of P. pinaster tannin-based foams and suggests the best thermal conductivity predictive model to use for organic foams according to the type of cells structure observed.
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Pinus pinaster tannin furanic foams part i formulation
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, M C Basso, Alain CelzardAbstract:a b s t r a c t New formulations of procyanidin tannin-based foams have been developed for the first time with mar- itime pine (Pinus pinaster) tannins. These tannins have an extremely high reactivity which makes them difficult to use for traditional tannin-based foams. For this work, an equipment named FOAMAT was used to record simultaneously temperature, pressure, velocity and dielectric polarization during foaming. The results highlight the role of surfactant (castor oil ethoxylate) and plasticizer (Polyethylene glycol) dur- ing foam formation: polymerization, expansion, hardening, and shrinkage. In this work, foams density - and its physical properties - are either surfactant or plasticizer-controlled. With polyethylene glycol and castor oil ethoxylate, homogeneous microstructure foams were obtained but polyethylene glycol made the foams more elastic and improved their shrinkage.
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hydroxypropyl tannin derivatives from Pinus pinaster ait bark
Industrial Crops and Products, 2013Co-Authors: D E Garcia, A Pizzi, Wolfgang G Glasser, Anayancy Osoriomadrazo, Mariepierre LaborieAbstract:Abstract Tannins from Pinus pinaster bark were modified with propylene oxide (PO) in aqueous alkali at room temperature (∼22 °C) for the first time. The hydroxypropylation to four different degrees of substitution (DS) produced derivatives (HPT) with monosubstituted phenolic functionalities in yields in excess of 80%. The isolated HPTs were characterized by FT-IR, UV–vis, 1H NMR and bidimensional spectroscopies (HMBC, HSQC and COSY). The integration of the aromatic proton signals in the 1H NMR spectra of acetylated HPT allowed for an easy quantitative determination of DS. HPTs possess properties that are expected to enhance their role in new oligomeric building-blocks for the synthesis of engineered plastics and tannin-based bio-foams.
Alain Celzard - One of the best experts on this subject based on the ideXlab platform.
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Pinus pinaster tannin furanic foams part ii physical properties
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, Alain CelzardAbstract:Foams with procyanidin-type tannins have been developed recently, more particularly with Pinus pinaster tannins. Mechanical properties in compression were tested. Thus, different thermal conductivity prediction models were compared with the experimental results. It was found that Glicksman model is the most suitable to predict radiative conductivity. The structure and cells size was determined by scanning electron microscopy. This paper gives for the first time physical properties of P. pinaster tannin-based foams and suggests the best thermal conductivity predictive model to use for organic foams according to the type of cells structure observed.
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Pinus pinaster tannin furanic foams part i formulation
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, M C Basso, Alain CelzardAbstract:a b s t r a c t New formulations of procyanidin tannin-based foams have been developed for the first time with mar- itime pine (Pinus pinaster) tannins. These tannins have an extremely high reactivity which makes them difficult to use for traditional tannin-based foams. For this work, an equipment named FOAMAT was used to record simultaneously temperature, pressure, velocity and dielectric polarization during foaming. The results highlight the role of surfactant (castor oil ethoxylate) and plasticizer (Polyethylene glycol) dur- ing foam formation: polymerization, expansion, hardening, and shrinkage. In this work, foams density - and its physical properties - are either surfactant or plasticizer-controlled. With polyethylene glycol and castor oil ethoxylate, homogeneous microstructure foams were obtained but polyethylene glycol made the foams more elastic and improved their shrinkage.
M P Laborie - One of the best experts on this subject based on the ideXlab platform.
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Hydroxypropyl tannin from Pinus pinaster bark as polyol source in urethane chemistry
European Polymer Journal, 2015Co-Authors: D E Garcia, A Pizzi, Wolfgang G Glasser, S. Paczkowski, M P LaborieAbstract:Novel thermosetting polyphenol-based polyurethane (PU) films were prepared using condensed tannin (CTs) and hydroxypropyl tannin derivatives (HPTs) from Pinus pinaster bark and diisocyanates. Four HPTs with a degree of substitution (DS) rising stepwise from 1 to 4 were crosslinked with either an aromatic (polymeric methylene diphenyl diisocyanate (pMDI)) or an aliphatic isocyanate (hexamethylene diisocyanate (HDI)). Chemical structure, moisture sorption, thermal, and morphological properties of the films were studied. Properties varies with NCO:OH ratio (0.5-4.0), DS, diisocyanate type, and cross-link density (CD). Partial tannin hydroxypropylation (DS 2, 3) based/films showed a flexible-type character in term of Young's modulus, elongation and tensile strain. Significant relationships were established between CD and physicochemical properties. HPTs constitute suitable macro building-block polyols for urethane chemistry.
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Pinus pinaster tannin furanic foams part ii physical properties
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, Alain CelzardAbstract:Foams with procyanidin-type tannins have been developed recently, more particularly with Pinus pinaster tannins. Mechanical properties in compression were tested. Thus, different thermal conductivity prediction models were compared with the experimental results. It was found that Glicksman model is the most suitable to predict radiative conductivity. The structure and cells size was determined by scanning electron microscopy. This paper gives for the first time physical properties of P. pinaster tannin-based foams and suggests the best thermal conductivity predictive model to use for organic foams according to the type of cells structure observed.
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Pinus pinaster tannin furanic foams part i formulation
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, M C Basso, Alain CelzardAbstract:a b s t r a c t New formulations of procyanidin tannin-based foams have been developed for the first time with mar- itime pine (Pinus pinaster) tannins. These tannins have an extremely high reactivity which makes them difficult to use for traditional tannin-based foams. For this work, an equipment named FOAMAT was used to record simultaneously temperature, pressure, velocity and dielectric polarization during foaming. The results highlight the role of surfactant (castor oil ethoxylate) and plasticizer (Polyethylene glycol) dur- ing foam formation: polymerization, expansion, hardening, and shrinkage. In this work, foams density - and its physical properties - are either surfactant or plasticizer-controlled. With polyethylene glycol and castor oil ethoxylate, homogeneous microstructure foams were obtained but polyethylene glycol made the foams more elastic and improved their shrinkage.
Clement Lacoste - One of the best experts on this subject based on the ideXlab platform.
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Pinus pinaster tannin furanic foams part ii physical properties
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, Alain CelzardAbstract:Foams with procyanidin-type tannins have been developed recently, more particularly with Pinus pinaster tannins. Mechanical properties in compression were tested. Thus, different thermal conductivity prediction models were compared with the experimental results. It was found that Glicksman model is the most suitable to predict radiative conductivity. The structure and cells size was determined by scanning electron microscopy. This paper gives for the first time physical properties of P. pinaster tannin-based foams and suggests the best thermal conductivity predictive model to use for organic foams according to the type of cells structure observed.
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Pinus pinaster tannin furanic foams part i formulation
Industrial Crops and Products, 2014Co-Authors: Clement Lacoste, A Pizzi, M P Laborie, M C Basso, Alain CelzardAbstract:a b s t r a c t New formulations of procyanidin tannin-based foams have been developed for the first time with mar- itime pine (Pinus pinaster) tannins. These tannins have an extremely high reactivity which makes them difficult to use for traditional tannin-based foams. For this work, an equipment named FOAMAT was used to record simultaneously temperature, pressure, velocity and dielectric polarization during foaming. The results highlight the role of surfactant (castor oil ethoxylate) and plasticizer (Polyethylene glycol) dur- ing foam formation: polymerization, expansion, hardening, and shrinkage. In this work, foams density - and its physical properties - are either surfactant or plasticizer-controlled. With polyethylene glycol and castor oil ethoxylate, homogeneous microstructure foams were obtained but polyethylene glycol made the foams more elastic and improved their shrinkage.
Helena Pereira - One of the best experts on this subject based on the ideXlab platform.
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properties of furfurylated wood Pinus pinaster
European Journal of Wood and Wood Products, 2011Co-Authors: Bruno Esteves, Lina Nunes, Helena PereiraAbstract:Sapwood samples of Pinus pinaster wood were treated with a 70% furfuryl alcohol mixture. Weight percent gain (WPG), equilibrium moisture content, dimensional stability, MOE, bending strength, hardness, density and durability were determined.
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heat induced colour changes of pine Pinus pinaster and eucalypt eucalyptus globulus wood
Wood Science and Technology, 2008Co-Authors: Bruno Esteves, Idalina Domingos, Antonio Marques, Helena PereiraAbstract:Heat treatment of Pinus pinaster and Eucalyptus globulus wood was carried out by hot air in an oven for 2–24 h at 170–200°C and by steam in an autoclave for 2–12 h at 190–210°C. The colour parameters L*, a* and b* were determined by the CIELAB method on radial, tangential and transverse sections of untreated and treated wood, and their variation with regard to the treatment (ΔL*, Δa* and Δb*) were calculated in percent. For untreated eucalypt wood, lightness (L*) varied between 54.1 and 63.8% with a* between 7.4 and 8.5, and b* between 15.7 and 19.9. For untreated pine wood, L* varied between 67.3 and 76.1%, a* between 6.9 and 7.6 and b* between 16.3 and 24.1. Oven heat-treated wood became darker (ΔL* about 50% for 4% mass loss), and this was more for eucalypt wood under the same treatment conditions. In general, the contribution of red (a*) and yellow (b*) colour decreased with heat treatment. The transverse section of the two species darkened less for both the treatments with small differences between radial and tangential sections. Lightness decrease was related to chemical changes; with good correlations with glucose (R2 = 0.96), hemicelluloses (R2 = 0.92) and lignin (R2 = 0.86). As regards colour, the heat treatments showed an interesting potential to improve the wood quality for solid timber products from pine and eucalypt.
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within tree variation of heartwood and ring width in maritime pine Pinus pinaster ait
Forest Ecology and Management, 2005Co-Authors: Sofia Knapic, Helena PereiraAbstract:Abstract The development of heartwood and sapwood in maritime pine (Pinus pinaster Ait.) in relation with tree and cambial age and growth rate was studied in ten trees randomly sampled at harvest (54–85-year-old) in a commercial stand in central Portugal. Average ring width at stem base was 1.84 ± 0.34 mm for 50 years of age. Growth rate decreased with cambial age and for the same cambial age increased along the stem with tree height. The number of heartwood rings was strongly correlated with cambial age. Heartwood formation was estimated to start at approximately 21 years of age and to proceed at a constant annual rate that increased with age (0.5 and 0.7 rings year−1 below and above 50 years of age). Within the tree, heartwood decreased with stem height, but in the lower part of the stem two patterns of variation were shown: a continuous decrease or an increase from stem base to a maximum at 2–3 m and a decrease afterwards. Sapwood radial width remained approximately constant within the tree and correlated positively with tree growth.
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genetic control of pulp and timber properties in maritime pine Pinus pinaster ait
Annals of Forest Science, 2002Co-Authors: David Pot, Helena Pereira, Philippe Rozenberg, Jose Carlos Rodrigues, Guillaume Chantre, Gwynn Lloyd Jones, Bjorn Hannrup, Christine Cahalan, Christophe PlomionAbstract:Wood is one of our most important natural resources and has been exploited for many hundreds of years as fuel, building material and a source of paper. Its composition is variable among and within species. The ability to monitor the intra-specific variability is a prerequisite to improve wood and end-products properties. This paper describes a study of the genetic control of a large set of wood properties, including growth, timber quality traits, wood chemical composition, kraft pulp production parameters and pulp properties, in a 12 × 12 half diallel of mari- time pine (Pinus pinaster Ait.). While relatively high (h ns 2 > 0.3) narrow-sense heritabilities were observed for density heterogeneity, lignin content, alpha-cellulose content and coarseness, no significant genetic effect was detected for hemi cellulose, water extractives, kraft pulp pro- duction parameters and pylodin. Slightly lower heritabilities (0.15 < h ns 2 < 0.3) were also obtained for wood density and fibre properties (length, width, curl, zero span). As a consequence and considering the phenotypic coefficient of variation obtained for these traits, improvement by selec- tion of trees with outstanding wood quality is feasible. Nevertheless, it seems obvious that wood quality breeding can not be done without taking into account growth, and the only way to manage this constraint (negative correlation between growth and density) will be the constitution of elite "wood quality" populations in a already growth improved genetic population.