Glycidyl methacrylate derivatized xylan-rich hemicelluloses: synthesis and characterizations

Abstract

In this paper, a novel type of hemicellulosic derivative containing polymerizable double bonds (C=C) was synthesized by chemical reaction of xylan-rich hemicelluloses and glycidyl methacrylate (GMA) in dimethyl sulfoxide (DMSO) in presence of catalysts. The chemical structure, reaction mechanism, and rheological properties of the derivative were investigated by means of FT-IR, 1 H and 13 C-NMR, DEPT 135 NMR, GC-MS and rheometer. The influence of the reaction conditions including reaction time, temperature, catalysts, and the amount of reagents on the degree of substitution were investigated in detail. Results showed that the chemical reaction of xylan-rich hemicelluloses with GMA was transesterification, which resulted in direct attachment of methacrylate (MA) groups to xylan-rich hemicelluloses, instead of GMA. A maximum degree of substitution of 0.94 could be achieved under the optimum reaction condition (40°C, 1.8 equiv of GMA to per xylose unit, 36 h, 20 % DMAP). Results from rheological analysis indicated that the aqueous solutions of the methacrylated xylan-rich hemicelluloses (MAXH; 0.5, 1.0 and 2.0 wt%) exhibited typical shear-thinning behavior in the range of shear rates tested. The viscoelasticity of MAXH solutions increased with the increasing concentration and DS.

Surface Engineered Biomimetic Inks Based on UV Cross-Linkable Wood Biopolymers for 3D Printing

“…Previously, methacrylated xylan and O -acetyl-galactoglucomannan (GGM) have been prepared in a rough manner involving toxic chemicals that were difficult to remove in the synthesis, such as 4-dimethyl-amino-pyridine (DMAP). 17−19 Thus, a greener approach would be needed to synthesize the methacrylated hemicelluloses in the context of bioink formulation. Moreover, the degree of substitution (DS) of methacrylates in the hemicellulose should be well tuned to provide adjustability to the mechanical properties of the engineered scaffold materials.…”

Comparative study on temperature/pH sensitive xylan-based hydrogels: their properties and drug controlled release

“…Peng et al introduced methacryloyl groups onto xylan-type hemicelluloses successfully by the transesterication reaction of xylan-type hemicelluloses with GMA in dimethyl sulfoxide (DMSO). 38 And then new photoresponsive hydrogels were prepared by the free radical copolymerization of GMA-modied xylan-type hemicelluloses with 4-[(4-acryloyloxyphenyl)azo]benzoic acid (AOPAB), 26 these hydrogels showed multi-responsive behaviors to pH, water/ethanol alternating solutions and light, which were indicative of an promising application in the light-controlled drug delivery system. Most pH sensitive hydrogels are attributed to graing carboxylic acid groups.…”

Synthesis of Acylated Xylan-Based Magnetic Fe3O4 Hydrogels and Their Application for H2O2 Detection

“…In addition, the degree of substitution (DS) of ACX was 0.63, which was determined by the contents of C, H, N, and S of the sample conducted via the elemental analysis [33]. The samples were ground into powder and dehydrated at 50 °C for 24 h. The DS values were calculated as follows [29]: $\mathrm{DS}=\frac{C\%\times 132-60}{36-55\times C\%}$ where C % is the carbon percentage of ACX tested by elemental analysis. 132 and 55 are the molecular weights (g/mol) of the xylose unit in xylan and the acryloyl group, respectively.…”

“…To improve the reactivity of hemicellulose, many studies have introduced alkenyl groups onto the backbone structure which could promote the reactions with other monomers to obtain the biocompatible macromolecular copolymers. Peng et al [ 29 ] designed a new kind of hemicellulosic derivative containing polymerizable carbon–carbon double bonds (C=C) via introduction of methacryloyl groups onto xylan-type hemicellulose. Multi-responsive hydrogels were designed by copolymerizing glycidyl methacrylate (GMA)-modified xylan-type hemicellulose with 4-[(4-acryloyloxyphenyl)azo] benzoic acid (AOPAB), and these hydrogels showed sensitive responses to pH, light, and water/ethanol alternating solutions, which were indicative of broad prospects in the application of light-controlled systems [ 27 ].…”