Polymer Chemistry Commons^™

Degumming Of Hemp Fibers Using Combined Microwave Energy And Deep Eutectic Solvent, Bulbul Ahmed

LSU Master's Theses

Hemp is considered as one of the sustainable agricultural fiber materials. Degumming or surface modification of hemp bast is needed to produce single fibers for ensuing textile and industrial applications. The traditional degumming process necessitates a high amount of alkali, which causes detrimental environmental pollution. This study offers a new method to degum hemp fibers with reduced use of harmful alkali and precious water resources. In this work, hemp bast fibers were degummed by using combined microwave energy and deep eutectic solvent (DES). The properties of hemp fibers manufactured by this method were investigated and compared with the traditional alkali …

Stretching The Applications Of Biomass: Development Of Lignin Based Thermoplastic Elastomers And Composite Materials, Anthony Stephen Bova

Doctoral Dissertations

Bio-based plastics and composites have seen increased industry adoption in recent years due to growing demand for materials with a low carbon footprint. The use of lignin as a feedstock for polymers has seen growing interest as the concept of an integrated cellulosic biorefinery gains traction and advances the need to use all components of separated biomass for value-added applications. Historically, use of lignin in thermoplastic and elastomeric copolymers and blends has been bottlenecked by the inability to introduce lignin content above 30 weight percent due to difficulties with interfacial adhesion of lignin with other soft segments. Efforts to overcome …

Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown

Sarah Cady

In this study, we methylated hydroxyl groups (phenolic hydroxyl: Phe-OH and aliphatic hydroxyl: Aliph-OH) in soda lignin (SL) prior to solvent liquefaction to improve storage stability of the resulting oil. We investigated two methylating reagents, dimethyl sulfate (DMS) and dimethyl carbonate (DMC), for selective Phe-OH and total hydroxyl group (Phe-OH and Aliph-OH) blocking. Samples of SL, DMS-SL, and DMC-SL were depolymerized into oils under supercritical ethanol (350 °C). Both methylated lignins produced higher amounts of oils and smaller amounts of char compared to untreated SL due to suppressed charring reactions. Oil produced from SL had relatively higher functional group contents …

Production And Applications Of Formaldehyde-Free Phenolic Resins Using 5-Hydroxymethylfurfural Derived From Glucose In-Situ, Yongsheng Zhang

Electronic Thesis and Dissertation Repository

The phenol-formaldehyde (PF) resin manufacturing industry is facing a growing challenge with respect to concerns over human health, due to the use of carcinogenic formaldehyde and sustainability due to the use of petroleum-based phenol in PF resin manufacture. Glucose and its derivative, 5-hydroxymethylfurfural (5-HMF), have proven to be potential substitutes for formaldehyde in the synthesis of phenolic novolac resins.

This thesis investigated a number of glucose and 5-HMF resin systems including the curing of phenol-glucose novolac resin (PG) with a bis-phenol-A type epoxy. The curing process was modeled according to the Sestak-Berggren equation (S, B) using Málek methods. This was …