Thermoplastics cellulosics

Properties. Ethyl cellulose [9004-57-3] (EC) is a nonionic, organo-soluble, thermoplastic cellulose ether, having an ethyl DS in the range of 2.2-2.7. Actually, EC is water-soluble at DS 1.2, but only those products that are thermoplastic and soluble in organic solvents are of commercial importance, because of thek abiUty to form tough, stable films. Above a DS of about 2.5, EC is soluble in many nonpolar solvents. 

During the time of the development of the urea-based resins, a thermoplastic, cellulose acetate, was making its debut. The material had earlier been extensively used as an aircraft dope and for artificial fibres. The discovery of suitable... 

Extrusion method to be used for thermoplastic cellulose derivatives)... 

ETHYL CELLULOSE. A versatile, thermoplastic cellulose ether that is compatible with a wide variety of solvent systems, resins, oils, and... 

The addn of certain nonionic surfactants (Tergicol XC or Arlacel C) to the molten mix of AN thermoplastic cellulose esters reduces the consistency of the molten mixr and the extrusion pressure needed to form a proplnt grain) K)P.O.Marti, L SP 2946672 (I960) CA 54, 25831 (I960) (The use of PVC in the binder of a comp proplnt improves the stability of the grain to thermal shock) L)F.B.Cramer, USP 2949352 (I960)... 

U.S. Pat. No. 6,844,040 [54] discloses a coextrusion process of making reinforced WPC structural members comprising hollow profiles formed from a thermoplastic-cellulose fiber composite material and reinforcing sections bonded to the hollow profile. 

The PVC-acrylic polymer alloy previously described is characterized by high speed injection moldability and, in sheet form, by deep drawing capability, both of which are the result of low melt viscosity. A cellulose-ethyl acrylate graft copolymer compatibilizes cellulose and PEA, cellulose and PVC, as well as starch and PVC (8). These compositions containing PVC obviously have better flow properties than non-thermoplastic cellulose or starch. However, they also have better flow properties than PVC alone. 

Chem. Descrip. Pigment disp. in diisononyl phthalate plasticizers Uses Colorant for thermoplastics (cellulose acetate-butyrate, cellulose acetate-propionate, polycarbonates, PVC) and thermosets (adhesives and coatings, film and sheeting, moldings and extrusion, plastisols and rubber) extender... 

This chapter first gives an overview of cellulose raw materials and their molecular and supermolecular structures. The principles of shaping cellulose into fibres, films, and nonwovens by means of solution techniques are then outlined followed by a section on properties and market applications of these materials. Derivatives of cellulose are presented with special emphasis on thermoplastic cellulose esters, typical plasticizers, and promising reinforcing materials. Finally, recent developments and future prospects of cellulose materials are reviewed as far as the above applications are concerned. This book does not cover the important applications of cellulose and ligno cellulose fibres for reinforcing thermoplastics, like wood plastic composites (WPC) and natural fibre reinforced plastics (NFRP), since in these cases cellulose does not substitute a thermoplastic. 

In particularly pure form and high crystallinity, cellulose is synthesized by certain bacteria (e.g. Acetobacter xylinus) and occurs in certain algae (e.g. Valonia ventricosa). These sources are important for basic research and are not used to produce thermoplastic cellulose material. 

J. Kalbe, H.P. Muller, R. Koch, J. Engelhardt, W. Koch, K. Szablikowski, and G. Weber, Thermoplastic cellulose ether ester graft copolymers and process for their production, US Patent 5 466 794, assigned to Wolff Walsrode Aktiengesellschaft (Walsrode, DE), November 14,1995. 

We already mentioned in Section 3.5 [70] the partial oxypropylation of cellulose fibres and the interest of the ensuing composite materials in which the unmodified fibre cores represent the reinforcing elements and their thermoplastic sleeves the source of a matrix. Other interesting approaches have been recently put forward to prepare composite materials in which cellulose or one of its derivatives prepared in situ are the only component. Glasser was the first to tackle this problem through the combination of cellulose esters and fibres by two distinct approaches, viz. (i) the incorporation of lyocell fibres into a cellulose acetate matrix [92] and (ii) the partial esterification of wood pulp fibres with -hexanoic anhydride in an organic medium [93] that produced thermally deformable materials in which the thermoplastic cellulose ester constituted the matrix and the unmodified fibres the reinforcing elements. 

Cellulose ester powders in the presence of different plasticizers and additives are extruded to produce various grades of commercial cellulose plastics in pelletized form. The nanoscale fillers can be mixed with these thermoplastic cellulose derivatives with the aid of plasticizers. Recently, Park et al. (2004) successfully used melt intercalation technique for the fabrication of cellulose nanocomposites fi om cellulose acetate (CA), triethylcitrate (TEC, as plasticizers), and organically modified clay. 

Phase behaviour and erystallisation kinetics for the binaiy blend P(3HB)/ eellulose propionate (CP) were performed by Maekawa et Cellulose aeetate butyrate (CAB), which has a combination of high (160 °C) and Tg (113 °C), is an important thermoplastic cellulose ester that can biodegrade in a natural environment. In an attempt to make the best use of degradable polyester P(3HB), Wang et al. blended P(3HB) with CAB and studied the relationship between the blend morphology and its physieal properties. 

Although it is linear, and nominally thermoplastic, cellulose is not readily soluble and will not flow below its decomposition temperature. 

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