Preparation of Molded Fiber Products from Hydroxylated Lignin Compounded with Lewis Acid-Modified Fibers Its Analysis

In this study, molded fiber products (MFPs) were prepared from lignin compounded with Lewis acid-modified fibers using enzymatic hydrolysis lignin (EHL) as a bio-phenol. The fibers were modified and compounded entirely through hot-pressing. To improve the reactivity of enzymatic lignin, hydroxylated enzymatic hydrolysis lignin (HEHL) was prepared by hydroxylation modification of purified EHL with hydrogen peroxide (H2O2) and ferrous hydroxide (Fe(OH)3). HEHL was mixed uniformly with Lewis acid-modified fibers on a pressure machine and modified during the molding process. The purpose of Lewis acid degradation of hemicellulose-converted furfural with HEHL was to generate a resin structure to improve the mechanical properties of a MFPs. The microstructure of the MFP was shown to be generated by resin structure, and it was demonstrated that HEHL was compounded on Lewis acid-modified fibers during the molding process. The thermal stability of the MFP with composite HEHL did not change significantly owing to the addition of lignin and had higher tensile strength (46.28 MPa) and flexural strength (65.26 MPa) compared to uncompounded and modified MFP. The results of this study are expected to promote the application of high lignin content fibers in molded fibers.

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Study on Properties of Enzymatic Hydrolysis Lignin (EHL) and Chloride Polyethylene (CPE) Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.1586 ◽

2013 ◽

Vol 690-693 ◽

pp. 1586-1589

Author(s):

Ai Bing Wang ◽

Xiang Wang ◽

Hong Hong ◽

Qi Wen Yin ◽

Yu Han Ye ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Enzymatic Hydrolysis ◽

Impact Strength ◽

Color Change ◽

Thermal Testing ◽

Hydrolysis Lignin ◽

Thermal And Mechanical Properties ◽

Stability Time ◽

Thermal Stability Of

Polymer blends consisting of chloride polyethylene (CPE), and enzymatic hydrolysis lignin(EHL) were prepared by compression molding. The thermal and mechanical properties of EHL-CPE composites were investigated. The results showed that the presence of EHL, which interfered with the intramolecular and intermolecular interactions and Impact strength of CPE were improved. The values of impact strength and thermal stability time rose quickly with ncreasingEHL content from 5 to 20 phr.There was a obvious increase color change time in Congo red dipstick experiment of CPE by adding EHL. The thermal testing results showed that EHL could be a novel additive for increasing thermal stability of CPE.

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Synthesis and Flame Retardant Properties of Melamine Modified EH Lignin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.482 ◽

2011 ◽

Vol 236-238 ◽

pp. 482-485 ◽

Cited By ~ 3

Author(s):

Ru Lin Fu ◽

Xian Su Cheng

Keyword(s):

Thermal Stability ◽

Enzymatic Hydrolysis ◽

Flame Retardant ◽

Flame Retardancy ◽

Hydrolysis Lignin ◽

Char Residue ◽

Red Phosphorus ◽

Environmental Friendly ◽

Flame Retardant Properties ◽

Thermal Stability Of

A novel intumescent ﬂame retardant (IFR), melamine modified enzymatic hydrolysis lignin (MEHL), was synthesized and well characterized by FTIR and TGA. The results showed that the decompose temperature of MEHL is much higher than that of enzymatic hydrolysis lignin (EHL). In order to improve ﬂame retardancy and dripping resistance of EPDM, MEHL and microencapsulated red phosphorus (MRP) were added into EPDM as IFR system. The ﬂame ability and thermal stability of IFR and EPDM composites were investigated by UL-94 vertical burning test and LOI measurements. The results indicated that FV-0 was reached and the LOI value was 35 when per hundred rubber (phr) together with 12 phr MRP and 50 phr EHLM were added. SEM photos showed that the char residue was continuous, and a barrier between flame and rubber was formed, while there were also small holes in its surfaces. On all accounts, EHL used as a carbonization agent instead of petroleum chemicals, such as pentaerythritol, was more environmental friendly and beneficial to economy.

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Preparation and Characterization of Lignin-Phenolic Foam

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1014 ◽

2011 ◽

Vol 236-238 ◽

pp. 1014-1018 ◽

Cited By ~ 2

Author(s):

Xiao Wei Zhuang ◽

Shou Hai Li ◽

Yu Feng Ma ◽

Wei Zhang ◽

Yu Zhi Xu ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Oxygen Index ◽

Lignin Content ◽

Fire Retardant ◽

Micro Structure ◽

Critical Oxygen ◽

Hole Structure ◽

Thermal Stability Of

In this paper, lignin could partly replaced phenol to prepare lignin-phenolic(LPF) foam.The effects of amount of lignin on mechanical properties, thermal stability, fire-retardant and micro-structure of LPF foam. The results indicated that the addition of lignin decreased the brittleness and flexibility of foam, and the foam hole became larger in diameter and distributed more unevenly. When the lignin replacement amount was lower, the foam had regular foam hole structure and even distribution of foam hole, the size of foam hole increased with an increase of lignin content, SEM observations were in accordance with the early research of the mechanical properties of foams. And the addition of lignin slightly affected the fire-retardant and thermal stability of foam. When lignin replacement amount was 30% and 40%, the critical oxygen index of foam was even slightly higher than the pure PF foam.

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Controlling the Thermal Stability of Kyanite-Based Refractory Geopolymers

Materials ◽

10.3390/ma14112903 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2903

Author(s):

Juvenal Giogetti Nemaleu Deutou ◽

Rodrigue Cyriaque Kaze ◽

Elie Kamseu ◽

Vincenzo M. Sglavo

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

High Strength ◽

Treatment Temperature ◽

Strength Development ◽

Particle Sizes ◽

Cold Setting ◽

Thermal Stability Of ◽

Geopolymer Composites ◽

Refractory Composites

The present project investigated the thermal stability of cold-setting refractory composites under high-temperature cycles. The proposed route dealt with the feasibility of using fillers with different particle sizes and studying their influence on the thermo-mechanical properties of refractory geopolymer composites. The volumetric shrinkage was studied with respect to particle sizes of fillers (80, 200 and 500 µm), treatment temperature (1050–1250 °C) and amount of fillers (70–85 wt.%). The results, combined with thermal analysis, indicated the efficiency of refractory-based kyanite aggregates for enhancing thermo-mechanical properties. At low temperatures, larger amounts of kyanite aggregates promoted mechanical strength development. Flexural strengths of 45, 42 and 40 MPa were obtained for geopolymer samples, respectively, at 1200 °C, made with filler particles sieved at 80, 200 and 500 µm. In addition, a sintering temperature equal to 1200 °C appeared beneficial for the promotion of densification as well as bonding between kyanite aggregates and the matrix, contributing to the reinforcement of the refractory geopolymer composites without any sign of vitrification. From the obtained properties of thermal stability, good densification and high strength, kyanite aggregates are efficient and promising candidates for the production of environmentally friendly, castable refractory composites.

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