scholarly journals Influence of residual lignin content on physical and mechanical properties of kraft pulp/pp composites

2014 ◽  
pp. 0-0 ◽  
Author(s):  
Majid Kiae ◽  
Behzad Kord ◽  
Ramin Vaysi
Keyword(s):  
Mechanical Properties ◽  
Kraft Pulp ◽  
Lignin Content ◽  
Physical And Mechanical Properties ◽  
Residual Lignin ◽  
Pp Composites

Lignin modification in the initial phase of softwood kraft pulp delignification with polyoxometalates (POMs)

Holzforschung ◽  
2007 ◽  
Vol 61 (5) ◽  
pp. 492-498 ◽  
Author(s):  
Biljana Bujanovic ◽  
Sally A. Ralph ◽  
Richard S. Reiner ◽  
Rajai H. Atalla
Keyword(s):  
Kraft Pulp ◽  
Lignin Content ◽  
Kappa Number ◽  
Ring Cleavage ◽  
Residual Lignin ◽  
Glucose Content ◽  
Lower Glucose ◽  
Softwood Kraft Pulp ◽  
Alkaline Conditions ◽  
Extraneous Material

Abstract Commercial softwood kraft pulp with kappa number 30.5 (KP30.5) was delignified with polyoxometalates (POM, Na5(+2)[SiV1(-0.1)MoW10(+0.1)O40]), and POM-treated kraft pulp of kappa number 23.6 was obtained (KPPOM,23.6). Residual lignin from pulps was isolated by mild acid hydrolysis and characterized by analytical and spectral methods to gain insight into lignin reactions taking place during the initial delignification phase. Lignin from POM-delignified pulp was isolated in lower yield. Comparative analysis of residual lignins (RL-KP30.5, RL-KPPOM,23.6) showed that POM leads to products enriched in carbonyl/carboxyl groups and carbohydrates. POM lignins have a lower molecular mass and a lower content of phenolic hydroxyl and methoxyl groups. Based on these results and FTIR spectra, we suggest that aromatic ring cleavage and quinone formation occur during POM delignification. The degree of lignin-cellulose association increases after POM delignification. Lignin-cellulose association was found to be partially unstable under mild alkaline conditions, as residual lignin isolated after alkaline extraction of KPPOM,23.6 pulp (RL-KPPOM/NaOH) exhibited lower glucose content, higher Klason lignin content, and less extraneous material.

scholarly journals Nanostructured Films Produced from the Bleached Pinus sp. Kraft Pulp

2019 ◽  
Vol 26 (4) ◽  
Author(s):  
Lívia Cássia Viana ◽  
Graciela Ines Bolzon de Muñiz ◽  
Washington Luiz Esteves Magalhães ◽  
Alan Sulato de Andrade ◽  
Silvana Nisgoski ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Kraft Pulp ◽  
Physical And Mechanical Properties ◽  
Compact Structure ◽  
Nanostructured Films ◽  
Bleached Kraft Pulp ◽  
Lower Porosity ◽  
Density Values ◽  
Number Of Passes

ABSTRACT This study investigates the physical and mechanical properties of nanostructured films produced from Pinus sp. kraft pulp. To obtain the nanocellulose, the bleached kraft pulp was submitted to six different grinding regimes: two, five, ten, 20, 30, and 40 passes through the grinder. The influence of the number of passes was evaluated through the films’ physical and mechanical properties. The results show that the nanofibers reduced the thickness and considerably increased the density values of the fabricated films. The tensile strength increased more than 300% and the burst index was ten times higher in relation to normal papers. The more compact structure and lower porosity caused by the larger contact surface between nanofibers in the nanostructured films resulted in higher values of density, tensile strength, and burst resistance.

scholarly journals Comprehensive elucidation of the effect of residual lignin on the physical, barrier, mechanical and surface properties of nanocellulose films

2015 ◽  
Vol 17 (3) ◽  
pp. 1853-1866 ◽  
Author(s):  
Ester Rojo ◽  
Maria Soledad Peresin ◽  
William W. Sampson ◽  
Ingrid C. Hoeger ◽  
Jari Vartiainen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Surface Properties ◽  
Physical And Mechanical Properties ◽  
Residual Lignin ◽  
Physical Barrier ◽  
Lignocellulose Nanofibrils

We elucidate the effect of residual lignin on the interfacial, physical and mechanical properties of lignocellulose nanofibrils (LCNF) and respective nanopapers.

scholarly journals Fabrication and Study of Mechanical and Thermal Properties of Natural Fibre Composites Material Based on SCB and GNSP

2019 ◽  
pp. 51-56
Author(s):  
Himanshu Gupta ◽  
Kamal Kanaujiya ◽  
Syed Mazher Abbas Rizvi
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Polymer Matrix ◽  
Physical And Mechanical Properties ◽  
Natural Fibre ◽  
Environmental Benefits ◽  
Mechanical And Thermal Properties ◽  
Izod Impact Strength ◽  
Izod Impact ◽  
Pp Composites

To determine the possibility of using sugar- cane bagasse (SCB)and ground nut shell particulate(GNSP) waste as reinforcing ?ller in the thermo plastic polymer matrix, SCB&GNSP-reinforced polypropylene (PP) composites were prepared. The PP and SCB and GNSP composites were prepared by the extrusion of PP and GNSP with 5, 10, 15, and 20 wt % of SCB and GNSP with 3,6,9 and 12% filler in a co rotating twin screw extruder.. The extruded strands were cut into pellets and injection molded to make test specimens. These specimens were tested for physical and mechanical properties such as tensile, flexural, Izod impact strength shore D hardness and water absorption. It was found that the Tensile strength increased from 29.06 to 31.38 MPa, Flexural strength increased from 28.62 to 43.56 MPa, Izod impact strength decreased from 35.11 to 30.93 J/m, and Shore D Hardness increased from 64.88 to 77.89, with increase in filler loading from 5 to 20% in the PP matrix. The decrease in Izod Impact strength and elongation with addition of SCB & GNSP filler to PP matrix follows the general trend of filler effects on polymer matrix. However, the main purpose of this work was to study the effect of SCB & GNSP waste on the mechanical properties of the PP Composites. The SCB and GNSP waste can be used as filler in the PP composites, which will reduce cost and give environmental benefits.

Pulping-tailored fiber properties from a novel Brazilian Eucalyptus hybrid

Holzforschung ◽  
2014 ◽  
Vol 68 (3) ◽  
pp. 273-282 ◽  
Author(s):  
Marcelo Coelho dos Santos Muguet ◽  
Fernando José Borges Gomes ◽  
Kyösti Ruuttunen ◽  
Leena-Sisko Johansson ◽  
Anna-Stiina Jääskeläinen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Photoelectron Spectroscopy ◽  
Lignin Content ◽  
Eucalyptus Grandis ◽  
Physical And Mechanical Properties ◽  
Pulp Fibers ◽  
Fiber Properties ◽  
Thermomechanical Pulping ◽  
Bulk Chemical

Abstract The chemical composition and morphology of pulp fibers have a significant impact on the properties of fiber products. Pulp samples from a novel unique Eucalyptus triple hybrid [Eucalyptus grandis × (Eucalyptus urophylla × Eucalyptus globulus)] were obtained by various pulping processes – kraft, soda-anthraquinone (NaOH-AQ), and thermomechanical pulping (TMP). The chemical composition of the fiber surfaces was evaluated by X-ray photoelectron spectroscopy (XPS). The surface lignin content of NaOH-AQ pulp fibers was lower than that of the kraft counterpart. However, kraft pulp handsheets showed better physical and mechanical properties. XPS data strongly suggests that together with the pulp bulk chemical composition the xylan is more abundant on the surface of kraft fibers, which is reflected on their better mechanical properties. Moreover, the relatively low surface lignin content in TMP pulp compared to wood suggests that defibration takes place in the secondary wall, where lignin is less concentrated.

scholarly journals PROPRIEDADES TECNOLÓGICAS DA MADEIRA DE EUCALIPTO SUBMETIDA AO TRATAMENTO TÉRMICO

Nativa ◽  
2018 ◽  
Vol 6 (5) ◽  
pp. 537
Author(s):  
Claudio Gumane Francisco Juizo ◽  
Lineia Roberta Zen ◽  
Walderson Klitzke ◽  
Morgana Cristina França ◽  
Vitor Gonçalves Cremonez ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lignin Content ◽  
Chemical Properties ◽  
Physical And Mechanical Properties ◽  
Heat Treatments ◽  
Modulus Of Rupture ◽  
Technological Properties ◽  
Limit Condition ◽  
Heat Treated ◽  
Eucalyptus Wood

Este trabalho teve o objetivo de avaliar as propriedades tecnológicas da madeira de Eucalyptus sp tratada termicamente. Foram utilizadas amostras de madeira previamente secas até 12% de umidade, as quais foram separadas em cinco tratamentos, sendo um testemunha e quatro condições de exposição sob elevadas temperaturas e tempo, utilizando um forno cerâmico. As amostras foram separadas para avaliação das propriedades químicas, físicas e mecânicas. Nos resultados obtidos, observou-se decréscimo do teor de extrativos totais e holoceluloses, enquanto o teor de lignina de Klason aumentou com a temperatura e tempo de exposição. Da mesma forma, os tratamentos térmicos causaram acréscimo da perda de massa e da efetiva repelência de água, com redução da massa específica aparente, taxa de absorção de água e higroscopicidade da madeira. Na resistência das peças verificou-se aumento do módulo de elasticidade (MOE) e diminuição do modulo de ruptura (MOR) com aplicação de tratamentos térmicos. Na compressão paralela verificou-se aumento do MOE e MOR nas peças tratadas, servindo de parâmetros para possibilidades de uso estrutural da madeira até ao estado limite último. A tensão de Dureza Janka decresceu com aplicação dos tratamentos térmicos limitando a utilização dos mesmos em projetos que requerem maior resistência na superfície.Palavras-chave: Temperatura, Propriedades químicas, Propriedades físicas, Propriedades mecânicas. TECHNOLOGICAL PROPERTIES OF THE EUCALYPTUS WOOD UNDER THE HEAT TREATMENT  ABSTRACT:This work aimed to evaluate the technological properties of the heat treated wood of Eucalyptus sp. Were used wood samples Pre-dried up to 12% of moisture, which were separated into five treatments, one control and four diferente exposure conditions under high temperatures and time using a ceramic kiln. The samples were separated for evaluation of chemical, physical and mechanical properties. In the obtained results there was a decrease in total extractive and holocelluloses contents, while the Klason lignin content increased with the temperature and exposure times. In the same way, the heat treatments caused an increase of the mass loss and the effective water repellency with reduction of the apparent specific gravity, rate of water absorption and hygroscopicity of the wood. In the resistance of the pieces, the modulus of elasticity (MOE) was increased and the modulus of rupture (MOR) was reduced under the heat treatments. In the Parallel compression was verified increasing of MOE and MOR of the heat treated samples, serving as parameters for possibilities of structural use of the wood up to the last limit condition. The Janka hardness tensile decreased with the application of heat treatments, limiting the use of the wood in projects that require higher surface resistance.Keywords: temperature, chemical properties, physical properties, mechanical properties.

Polyhydric Alcohol Pulping at Atmospheric Pressure: An Effective Method for Organosolv Pulping of Softwoods

Holzforschung ◽  
1999 ◽  
Vol 53 (4) ◽  
pp. 411-415 ◽  
Author(s):  
Yasumitsu Uraki ◽  
Yoshihiro Sano
Keyword(s):  
Mechanical Properties ◽  
Atmospheric Pressure ◽  
Kraft Pulp ◽  
Kappa Number ◽  
Polyhydric Alcohol ◽  
Sodium Chlorite ◽  
Cellulose Content ◽  
Residual Lignin ◽  
Bleached Pulp ◽  
Very High

Summary Polyhydric alcohol pulping was developed to separate components of low-quality softwoods that are produced by thinning and improvement cutting as well as to establish a self-supporting pulping system. Propylene glycol (PG) was superior to ethylene glycol (EG) as solvent for polyhydric alcohol pulping at atmospheric pressure. PG pulping of fir, larch and cedar, with sulfuric acid as a catalyst, gave satisfactory pulps with few rejects and a very low level of residual lignin as compared with EG pulping. The PG pulps were readily bleached to approximately Kappa number 1 and 80% brightness by one treatment with sodium chlorite. The yield of bleached pulp from fir was 44.7% based on chips. The bleached pulps had very high α-cellulose content and crystallinity, and their mechanical properties were similar to those of kraft pulp. Therefore, polyhydric alcohol pulping appears to be promising for pulping of softwoods by an organosolv method.

scholarly journals Physical and Mechanical Properties of Briquettes Produced from Energy Plants

2017 ◽  
Vol 65 (1) ◽  
pp. 219-224 ◽  
Author(s):  
Oľga Urbanovičová ◽  
Koloman Krištof ◽  
Pavol Findura ◽  
Ján Jobbágy ◽  
Marek Angelovič
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Lignin Content ◽  
Physical And Mechanical Properties ◽  
Calorific Value ◽  
Energy Crops ◽  
Miscanthus Sinensis ◽  
Mechanical Resistance ◽  
Rosa Multiflora ◽  
Particle Size Range

The study deals with the use of energy crops for the production of thermal energy in the form of briquettes and devising appropriate parameters for their production. Briquettes were produced from seven kinds of energy crops, Salix viminalis, Miscanthus sinensis, Rosa multiflora, Polygonum sachalinensis, Helianthus tuberosus, Sida hermaphrodita and Spartina pectinata, specifically. In the production of briquettes, moisture is the most important properties of material to be pressed, which ranges from 8 to 15 % as it was observed. At a higher humidity it has not been possible to produce briquettes farther in the study conditions. Another important condition for the successful production of briquettes was the particle size of chopped mass. The optimum particle size range from 8 to 20 %. The briquettes were pressed at a pressure of 21 MPa and with diameter of 50 %. Subsequently, physical and mechanical properties (density, moisture, mechanical resistance) and chemical properties (chlorine, iron, nitrogen, calcium, ash, lignin content) were measured. The briquettes density reached from 800 to 900 kg.m−3 with calorific value from 14 to 19 MJ.kg−1 which refers to fact that energy crops are competitive to fossil fuels by their calorific value.

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