# LignoStarch Tailored modification of starch by radiation-grafting of lignin

Dhriti Khandal, Christophe Bliard, X. Coqueret, Pierre-Yves Mikus, Patrice Dole, Stephanie Baumberger, Jeremie Soulestin, Marie France Lacrampe

► To cite this version:

Dhriti Khandal, Christophe Bliard, X. Coqueret, Pierre-Yves Mikus, Patrice Dole, et al., LignoStarch Tailored modification of starch by radiation-grafting of lignin. ANR SUSTAINABLE CHEMISTRY CONFERENCE, Oct 2012, Lyon, France., 2012. [hal-02279995](https://hal.science/hal-02279995)

HAL Id: hal-02279995

https://hal.science/hal-02279995

Submitted on 5 Sep 2019

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons Attribution 4.0 International License
D. Khandal,¹) C. Bliard,¹) X. Coqueret,¹) P. Y. Mikus,²) P. Dole,²)
S. Baumberger,³) J. Soules tin,⁴) and M.F. Lacrampe⁴)

1) ICMR, UMR CNRS 7312, 2) FARE, UMR INRA, Université de Reims Champagne Ardenne,
3) INRA UMR 1318 Institut JPB - AgroParisTech Versailles, 4) DTPCIM - Ecole des Mines de Douai

<figure><img src="image_2.png" /></figure>

### Introduction

Thermoplastic Starch (TPS) represents ca 80% of the biopolymer market, however, unlike petroleum based polymers, TPS is still manufactured by traditional methods of extrusion and injection molding.

Starch is a semi-crystalline renewable biopolymer made of glucose units existing as a mixture of linear polymer chains (amylose) and branched polymer chains (amylopectin). Due to its hydrophilic nature, starch products show retrogradation and varying mechanical properties with time.

<figure><img src="image_3.png" /></figure>

Amylose: Linear polymer chain with α (1,4) branching between glucose monomer units.

<figure><img src="image_4.png" /></figure>

Amylopectin: Polymer chain with α (1,4) and α (1,6) branching between glucose monomer units.

Lignin, another renewable biopolymer and a by-product of the paper industry is hydrophobic and limits water sensitivity of TPS blends. Electron Beam radiation-induced grafting of lignin models onto starch/maltodextrin is shown to result in physical stability of the blends with limited loss of mechanical properties, improved *surface hydrophobicity*, and to impede long-term retrogradation.

<figure><img src="image_5.png" /></figure>

<figure><img src="image_6.png" /></figure>

<figure><img src="image_7.png" /></figure>

### Concept

<figure><img src="image_8.png" /></figure>

Structural Modifications From : Scission, Crosslinking, Grafting

The research was carried out in 4 domains:
Method development, Mechanical Properties,
Surface Properties, and Radiation-induced
modifications.

<figure><img src="image_9.png" /></figure>

<figure><img src="image_10.png" /></figure>

<figure><img src="image_11.png" /></figure>

<figure><img src="image_12.png" /></figure>

<figure><img src="image_13.png" /></figure>

10 MeV

<figure><img src="image_14.png" /></figure>

<figure><img src="image_15.png" /></figure>

<figure><img src="image_16.png" /></figure>

### Surface and Mechanical Properties

Surface hydrophilicity decreases of the starch lignin blends after irradiation.

Starch : Glycerol : Lignins = 70 : 30 : 20 or 30 parts by wt

* Lignosulfonates (LS)

* Wheat liginins (WL)

* Bagasse lignins (BagL)

<figure><img src="image_17.png" /></figure>

Mechanical Properties can be modified in presence of Lignin-like additives. Radiation-induced grafting of aromatic additives competes chain scission. Final blend properties depend on blend composition and radiation parameters.

<figure><img src="image_18.png" /></figure>

<figure><img src="image_19.png" /></figure>

<figure><img src="image_20.png" /></figure>

<figure><img src="image_21.png" /></figure>

### Modifications at Molecular Level

* Grafting of aromatic additives overcome chain scission

* Radiochemical yields G(S) and G(X) determined f ( [arom] )

* H-bonding and supramolecular interactions affect reactivity

<figure><img src="image_22.png" /></figure>

### Salient Results

* Hydrophobic surfaces can be obtained with θ<sub>water</sub> >110°

* Mechanical properties can be modified in presence of lignin-like monomers despite the ever existing chain scission

* Deformation breaking mechanisms monitored by videotraction

* Composition (plasticizer, aromatic additive) and radiation parameters determine final properties

* Aromatic additives exert strong protective effect against scission

* Starch molecular architecture can be tailored as desired

<figure><img src="image_23.png" /></figure>

### Conferences and Publications

Award at IRaP 2010 conference, Bethesda MD
Invited conferences at IMRaP 2011, Tihany Radiation Conference 2011, Gordon Research Conference on Radiation Chemistry 2012

Baumberger et al., *J. Agric Food Chem*, 1998, 46, 2234-2240

Lepifre et al., *Biomacromolecules*, 2004, 5, 1678-1686

Khandal et al., *Radiat. Phys. Chem.* 2012, Vol 81, No. 8 (2012), 986-990

Khandal et al., *Radiat. Phys. Chem.*, in press

3 other publications are in process of review or submission

### CONTACT :

Prof. Xavier Coqueret, Institut Chimie Moléculaire de Reims, URCA Reims
xavier.coqueret@univ-reims.fr

<figure><img src="image_24.png" /></figure>

ICMR

Institut de Chimie Moléculaire de Reims
UMR CNRS 7312

<figure><img src="image_25.png" /></figure>

IRA

UNIVERSITÉ DE REIMS CHAMPAGNE-ARDENNE

<figure><img src="image_26.png" /></figure>

<figure><img src="image_27.png" /></figure>

AgroParisTech

INSTITUT DES SCIENCES ET INDUSTRIES DU CUVÉNANT ET DE L'ENVIRONNEMENT

<figure><img src="image_28.png" /></figure>

École d'Ingénieurs
Centrale de Recherche
Mines de Douai
LILLE EUROPÉIEN