{
  "abstract": "Carboxymethylated tara gum (CMTG) is an anionic galactomannan whose macroscopic behavior depends on the interplay between degree of substitution (DS), molecular degradation, and charge density. In this work, a rapid microwave-assisted carboxymethylation strategy was developed and optimized using response surface methodology and compared with a conventional reflux etherification method. Microwave irradiation enabled reproducible substitution levels close to unity (DSCM ≈ 1.0) within 20 min, compared with 3 h under reflux conditions, but simultaneously promoted significant alkaline-induced chain fragmentation. Spectroscopic analyses (FTIR, ¹H and ¹³C NMR) confirmed successful etherification, whereas SEC analysis revealed multimodal molecular weight distributions with substantial low-molecular-weight fractions generated under microwave processing. Rheological analysis demonstrated that carboxymethylation markedly reduced the zero-shear viscosity (η₀) from 6.55 Pa·s for native tara gum to 0.59–1.99 Pa·s for CMTG derivatives, together with a reduction in relaxation time (λ) from 0.62 to 0.18 s, indicating decreased chain entanglement and faster structural relaxation. Despite this molecular fragmentation, highly substituted microwave-synthesized CMTG exhibited pronounced shear-thinning behavior, improved water solubility, and enhanced viscoelastic responsiveness associated with electrostatic chain expansion and charge-induced intermolecular interactions. Overall, microwave-assisted carboxymethylation provides a rapid and tunable route to engineer galactomannans with controllable substitution, molecular architecture, and rheological response for potential thickening, stabilization, and delivery applications.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "name": "Manuel Pariguana"
    },
    {
      "name": "Adolfo Marican"
    },
    {
      "name": "Ricardo Castro"
    },
    {
      "name": "Liz Gonzalez"
    },
    {
      "name": "Gustavo Cabrera-Barjas"
    },
    {
      "name": "Sekar Vijayakumar"
    },
    {
      "name": "Héctor Urra"
    },
    {
      "name": "Esteban F. Durán-Lara"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8bsqjq20383eh.bib",
  "cited_by": 1,
  "doi": "10.1016/j.mtcomm.2026.115545",
  "fulltext_url": null,
  "id": "8bsqjq20383eh",
  "issns": [
    "2352-4928"
  ],
  "landing_url": "https://hal.science/hal-05674933v1",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.phys"
    ],
    [
      "openalex",
      "1106|Polysaccharides Composition and Applications"
    ]
  ],
  "openalex": "W7164751278",
  "pdf_url": "https://hal.science/hal-05674933/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-06-13",
  "publisher": "Elsevier",
  "ris": "https://research.draconitic.com/paper/8bsqjq20383eh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:57Z",
      "native_id": "hal-05674933",
      "source": "hal",
      "url": "https://hal.science/hal-05674933v1"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "hal:0.phys",
      "subfield": "general"
    }
  ],
  "title": "Structure–property relationships in microwave-assisted carboxymethylated tara gum: Balancing substitution, molecular degradation, and rheology",
  "title_text": "Structure–property relationships in microwave-assisted carboxymethylated tara gum: Balancing substitution, molecular degradation, and rheology",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:57Z",
  "url": "https://research.draconitic.com/paper/8bsqjq20383eh",
  "venue": "Materials Today Communications",
  "versions": []
}