Lignin Waste Polyurethane Cushion Packaging Materials Research

2014 ◽  
Vol 488-489 ◽  
pp. 98-101
Author(s):  
Ju Wei Wang

Polyurethane (referred to as PU) is a polymer made from polyisocyanate and a polyether polyol or polyester polyol and small molecule polyol, polyamine or water chain extenders or crosslinking agent, such as raw materials. By changing the type of material and composition, you can dramatically change the form of products and their performance, the final product from soft to hard. Lignin, a natural renewable resources, natural aromatic polymer has a hydroxyl-containing three-dimensional structural characteristics, the research and application has become increasingly active. The introduction of the lignin in the material, not only can improve the performance of the material but also reduce costs, resulting in considerable economic benefits. If we can combine the two advantages of the manufacture of composite materials to become a demand. The subjects explored the impact of the alkali lignin waste polyurethane foam and curing agent on the performance of the polyurethane foam through experiments that the above factors, the ratio of the manufacture of polyurethane foam: phenolic resin 250g, adding emulsifier 30g, foamagent alkali lignin 40g, waste polyurethane 30g, hardener 100g from the foam strength of 380KPa and low cost.

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 499
Author(s):  
Duong Huu Hoang ◽  
Doreen Ebert ◽  
Robert Möckel ◽  
Martin Rudolph

The depletion of ore deposits, the increasing demand for raw materials, the need to process low-grade, complex and finely disseminated ores, and the reprocessing of tailings are challenges especially for froth flotation separation technologies. Even though they are capable of handling relatively fine grain sizes, the flotation separation of very fine and ultrafine particles faces many problems still. Further, the flotation of low-contrast semi-soluble salt-type minerals with very similar surface properties, many complex interactions between minerals, reagents and dissolved species often result in poor selectivity. This study investigates the flotation beneficiation of ultrafine magnesite rich in dolomite from desliming, currently reported to the tailings. The paper especially focuses on the impact of the depressant sodium hexametaphosphate (SHMP) on the following: (i) the froth properties using dynamic froth analysis (DFA), (ii) the separation between magnesite and dolomite/calcite, and (iii) its effect on the entrainment. As a depressant/dispersant, SHMP has a beneficial impact on the flotation separation between magnesite and dolomite. However, there is a trade-off between grade and recovery, and as well as the dewatering process which needs to be considered. When the SHMP increases from 200 g/t to 700 g/t, the magnesite grade increases from 67% to 77%, while recovery decreases massively, from 80% to 40%. The open circuit with four cleaning stages obtained a concentrate assaying 77.5% magnesite at a recovery of 45.5%. The dolomite content in the concentrate is about 20%, where 80% of dolomite was removed and importantly 98% of the quartz was removed, with only 0.3% of the quartz in the final concentrate. Furthermore, the application of 1-hydroxyethylene-1,1-diphosphonic acid (HEDP) as a more environmentally friendly and low-cost alternative to SHMP is presented and discussed. Using only 350 g/t of HEDP can achieve a similar grade (76.3%), like 700 g/t of SHMP (76.9%), while obtaining a 17% higher magnesite recovery as compared to 700 g/t of SHMP. Interestingly, the proportion of hydrophilic quartz minerals ending up in the concentrate is lower for HEDP, with only 1.9% quartz at a recovery of 21.5% compared to the 2.7% of quartz at a recovery of 24.9% when using SHMP. The paper contributes in general to understanding the complexity of the depressant responses in froth flotation.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Fan Qi ◽  
Zhang Chaoqun ◽  
Yang Weijun ◽  
Wang Qingwen ◽  
Ou Rongxian

Abstract On the basis of the world’s continuing consumption of raw materials, there was an urgent need to seek sustainable resources. Lignin, the second naturally abundant biomass, accounts for 15–35% of the cell walls of terrestrial plants and is considered waste for low-cost applications such as thermal and electricity generation. The impressive characteristics of lignin, such as its high abundance, low density, biodegradability, antioxidation, antibacterial capability, and its CO2 neutrality and enhancement, render it an ideal candidate for developing new polymer/composite materials. In past decades, considerable works have been conducted to effectively utilize waste lignin as a component in polymer matrices for the production of high-performance lignin-based polymers. This chapter is intended to provide an overview of the recent advances and challenges involving lignin-based polymers utilizing lignin macromonomer and its derived monolignols. These lignin-based polymers include phenol resins, polyurethane resins, polyester resins, epoxy resins, etc. The structural characteristics and functions of lignin-based polymers are discussed in each section. In addition, we also try to divide various lignin reinforced polymer composites into different polymer matrices, which can be separated into thermoplastics, rubber, and thermosets composites. This chapter is expected to increase the interest of researchers worldwide in lignin-based polymers and develop new ideas in this field.


2014 ◽  
Vol 3 (1) ◽  
pp. 57
Author(s):  
Abdelaziz Ghanemi ◽  
Besma Boubertakh

Pollution  represents  a  problem  common  to economy and  public  health. Indeed, the public health, because of the  divers’  type of pollutions, is facing divers challenges for which urgent solutions are required.The biology provides approaches not only to deal with the pollution, but also to  obtain  economic  benefits. Some living  organisms  have  particular metabolisms  that allow  them  to  assimilate  and  metabolite  the polluting agents  and thus reduce the  impact  they have on both environment  and public health.  On  the other  hand,  the  metabolic  properties  of  specific organisms make  the  polluting  elements raw materials to  synthesize  other elements that are benefits  for  economy  and  non-toxic  for  the  ecology and  the  biohealth. Yet, other options such as the regulations and laws are  required  to improve the efficiency of these approaches.


Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1873
Author(s):  
Petronela Pascariu ◽  
Niculae Olaru ◽  
Aurelian Rotaru ◽  
Anton Airinei

A new type of material based on carbon/ZnO nanostructures that possesses both adsorption and photocatalytic properties was obtained in three stages: cellulose acetate butyrate (CAB) microfiber mats prepared by the electrospinning method, ZnO nanostructures growth by dipping and hydrothermal methods, and finally thermal calcination at 600 °C in N2 for 30 min. X-ray diffraction (XRD) confirmed the structural characteristics. It was found that ZnO possesses a hexagonal wurtzite crystalline structure. The ZnO nanocrystals with star-like and nanorod shapes were evidenced by scanning electron microscopy (SEM) measurements. A significant decrease in Eg value was found for carbon/ZnO hybrid materials (2.51 eV) as compared to ZnO nanostructures (3.21 eV). The photocatalytic activity was evaluated by studying the degradation of three dyes, Methylene Blue (MB), Rhodamine B (RhB) and Congo Red (CR) under visible-light irradiation. Therefore, the maximum color removal efficiency (both adsorption and photocatalytic processes) was: 97.97% of MB (C0 = 10 mg/L), 98.34% of RhB (C0 = 5 mg/L), and 91.93% of CR (C0 = 10 mg/L). Moreover, the value of the rate constant (k) was found to be 0.29 × 10−2 min−1. The novelty of this study relies on obtaining new photocatalysts based on carbon/ZnO using cheap and accessible raw materials, and low-cost preparation techniques.


2018 ◽  
Vol 52 (25) ◽  
pp. 3429-3444 ◽  
Author(s):  
Ezequiel Buenrostro ◽  
Daniel Whisler

Three-dimensional fiber-reinforced foam cores may have improved mechanical properties under specific strain rates and fiber volumes. But its performance as a core in a composite sandwich structure has not been fully investigated. This study explored different manufacturing techniques for the three-dimensional fiber-reinforced foam core using existing literature as a guideline to provide a proof of concept for a low-cost and easily repeatable method comprised of readily available materials. The mechanical properties of the fiber-reinforced foam were determined using a three-point bend test and compared to unreinforced polyurethane foam. The foam was then used in a sandwich panel and subjected to dynamic loading by means of a gas gun (103 s−1). High-strain impact tests validated previously published studies by showing, qualitatively and quantitatively, an 18–20% reduction in the maximum force experienced by the fiber-reinforced core and its ability to dissipate the impact force in the foam core sandwich panel. The results show potential for this cost-effective manufacturing method to produce an improved composite foam core sandwich panel for applications where high-velocity impacts are probable. This has the potential to reduce manufacturing and operating costs while improving performance.


2017 ◽  
Vol 23 (6) ◽  
pp. 1020-1031 ◽  
Author(s):  
Miguel Fernandez-Vicente ◽  
Ana Escario Chust ◽  
Andres Conejero

Purpose The purpose of this paper is to describe a novel design workflow for the digital fabrication of custom-made orthoses (CMIO). It is intended to provide an easier process for clinical practitioners and orthotic technicians alike. It further functions to reduce the dependency of the operators’ abilities and skills. Design/methodology/approach The technical assessment covers low-cost three-dimensional (3D) scanning, free computer-aided design (CAD) software, and desktop 3D printing and acetone vapour finishing. To analyse its viability, a cost comparison was carried out between the proposed workflow and the traditional CMIO manufacture method. Findings The results show that the proposed workflow is a technically feasible and cost-effective solution to improve upon the traditional process of design and manufacture of custom-made static trapeziometacarpal (TMC) orthoses. Further studies are needed for ensuring a clinically feasible approach and for estimating the efficacy of the method for the recovery process in patients. Social implications The feasibility of the process increases the impact of the study, as the great accessibility to this type of 3D printers makes the digital fabrication method easier to be adopted by operators. Originality/value Although some research has been conducted on digital fabrication of CMIO, few studies have investigated the use of desktop 3D printing in any systematic way. This study provides a first step in the exploration of a new design workflow using low-cost digital fabrication tools combined with non-manual finishing.


2013 ◽  
Vol 29 (1) ◽  
pp. 112-117 ◽  
Author(s):  
Dominic Thewlis ◽  
Chris Bishop ◽  
Nathan Daniell ◽  
Gunther Paul

The objective quantification of three-dimensional kinematics during different functional and occupational tasks is now more in demand than ever. The introduction of new generation of low-cost passive motion capture systems from a number of manufacturers has made this technology accessible for teaching, clinical practice and in small/medium industry. Despite the attractive nature of these systems, their accuracy remains unproved in independent tests. We assessed static linear accuracy, dynamic linear accuracy and compared gait kinematics from a Vicon MX-f20 system to a Natural Point OptiTrack system. In all experiments data were sampled simultaneously. We identified both systems perform excellently in linear accuracy tests with absolute errors not exceeding 1%. In gait data there was again strong agreement between the two systems in sagittal and coronal plane kinematics. Transverse plane kinematics differed by up to 3° at the knee and hip, which we attributed to the impact of soft tissue artifact accelerations on the data. We suggest that low-cost systems are comparably accurate to their high-end competitors and offer a platform with accuracy acceptable in research for laboratories with a limited budget.


2018 ◽  
Vol 11 (4) ◽  
pp. 313-325
Author(s):  
Farshad Zamiri ◽  
Abdolreza Nabavi

AbstractMicrowave holography technique reconstructs a target image using recorded amplitudes and phases of the signals reflected from the target with Fast Fourier Transform (FFT)-based algorithms. The reconstruction algorithms have two or more steps of two- and three-dimensional Fourier transforms, which have a high computational load. In this paper, by neglecting the impact of target depth on image reconstruction, an efficient Fresnel-based algorithm is proposed, involving only one-step FFT for both single- and multi-frequency microwave imaging. Numerous tests have been performed to show the effectiveness of the proposed algorithm including planar and non-planar targets, using the raw data gathered by means of a scanner operating in X-band. Finally, a low-cost and high-speed hardware architecture based on fixed-point arithmetic is introduced which reconstructs the planar targets. This pipeline architecture was tested on field programmable gate arrays operating at 200 MHz clock frequency, which illustrates more than 30 times improvement in computation time compared with a computer.


Author(s):  
Viktor Vladimirovich Kogan

The article presents the empirical results of estimating the dependence of viscoplastic properties of the minced ordinary fish raw materials from the kinematic and dynamic characteristics of mechanisms applied in the course of processing. When mixed in mechanical mixers, minced fish is subjected to shear and normal effects of rotating parts that create a complex three-dimensional flow. Optimization of the process of obtaining viscous-plastic culinary products depends on the dynamics of movement of the studied objects and the influence of working parts of various configurations. To establish the relationship between the duration of mixing, the angular speed of rotation of the working part of the horizontal mixer and general structural and mechanical properties of minced fish, there were carried out experimental studies using various types of mixer working parts: conveyer, screw and blade. The influence of the rotation speed of the mixer working part on the change in the rheological characteristics of the investigated raw materials has been confirmed. Specific energy costs should be emphasized as one of the main criteria for evaluating the performance of the supporting equipment. This parameter depends on redistribution of components during their mixing, changes in the structural and mechanical properties of minced fish and structural characteristics of the working parts. It has been stated that the lowest energy consumption and optimal mode for viscoplastic mixed mass can be achieved by using blades with an inclination angle to the axis of rotation = 20–30° and a humidity increase of mixed mass up to 0.7–0.8 kg/kg.


2020 ◽  
Author(s):  
Dorina Camelia Ilies ◽  
Tudor Caciora ◽  
Grigore Vasile Herman ◽  
Alexandru Ilies ◽  
Madalina Ropa ◽  
...  

Abstract The impact that geohazards have on cultural heritage requires continuous research in order to assess risks, prevention and conservation. This study has as the main research object, a uniquen monument in terms of its connection with the risk phenomena. It is about a wooden church historical monument from the village of Corbești, Romania, which was destroyed at the beginning of the tenth decade of the last century by a meteorological hazard, later reconstructed on a new site (in Oradea Municipality), and currently there is a risk of being affected by a geological hazard. The study focused on three main directions of research, namely: reconstructing the film of events, analyzing current risks and finding viable methods for future conservation and promotion. The methodology is based on extensive field research and the use of digital technologies. The results obtained confirmed the church's tendency to be affected by the emergence of a new risk phenomenon - landslides. In order to conserve and rebuild in case of need, the monument was digitized and a three-dimensional model of high accuracy was developed. This approach has the advantage of being low-cost, fast, non-invasive and providing large volumes of valuable information in the process of cultural heritage conservation.


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