US EPA

8717993 

Journal Article 

New branched chain cellulose derivatives based on Esparto "Stipa tenacissima" of eastern Morocco: Synthesis and characterization 

El Barkany, S; El Idrissi, A; Zanagui, C; Jilal, I; Tabaght, F; Abou-Salama, M; Amhamdi, H 

2017 

8 

4 

1195-1210 

English 

Cellulosic fibers, a renewable raw material, can be successfully modified with functionalized compounds yielding hydrophilic or hydrophobic and biodegradable substrates. Thus, the judicious choice of the polar/nonpolar balance, as well as, the length of the macromolecular segments of the coupling agent gave rise to a variety of interesting modified fibers, which could be tested in different areas of applications. An attempt was made to prepare new hydrophobic cellulose derivatives modified urethane/urea by reaction between various blocked HDI adducts and Hydroxyethyl Cellulose (HEC) prepared from Esparto plant "Stipa tenacissima" Cellulose. In the current study, the blocked HDI adducts were synthesized by reacting a series of monoalcohols or monoamines with hexamethylene diisocyanate. Cellulosic fibers were extracted from Esparto plant; their viscosity average molecular weight (Mw) was deduced from the intrinsic viscosity in DMAc/9% LiCl solution and found equal to Mw = 227200. Furthermore, HEC was prepared from these cellulosic fibers with etherification. The conventional spectroscopic structural characterization of the samples was affected by FTIR, 1H NMR and 13C NMR and they were in accordance with the proposed structures. The reaction products (HECU) were also characterized by FTIR, NMR, XRD, TG/TD, and contact angle. The results of data analyses gave sufficient proof of grafting. The crystalline behaviors of the synthesized polymers were investigated and found that crystallinity index decreased when passing from cellulose to HEC and showed a moderate variation in the case of HEC derivatives (urethane and urea). 2017, University of Mohammed Premier Oujda Morocco. 

Biopolymers; Cellulose; Modification