Polyesteramides properties

A further approach is used by Bayer with their polyesteramide BAK resins. A film grade, with mechanical and thermal properties similar to those of polyethylene is marketed as BAK 1095. Based on caprolactam, adipic acid and butane diol it may be considered as a nylon 6-co-polyester. An injection moulding grade, BAK 2195, with a higher melting point and faster crystallisation is referred to as a nylon 66-co-polyester and thus presumably based on hexamethylene diamine, adipic acid and butane diol. 

Aliphatic hyperbranched polyesters, 56 Aliphatic isocyanate adducts, 202 Aliphatic isocyanates, 210, 225 Aliphatic polyamides, 138 Aliphatic polyesteramides, 56 Aliphatic polyesters, 18, 20, 29, 32, 87 degradable, 85 hyperbranched, 114-116 melting points of, 33, 36 structure and properties of, 40-44 syntheses of, 95-101 thermal degradation of, 38 unsubstituted and methyl-substituted, 36-38... 

Figure 6.2 The polyesteramide structure proposed by Gaymans and co-workers E, ester group A, amide group [21]. Reprinted from Polymer, 38, van Bennekom, A. C. M. and Gaymans, R. J., Amide-modified polybutylene terephthalate structure and properties, 657-665, Copyright (1997), with permission from Elsevier Science...

Unfunctionalized, i.e., 2-hydroxypropylamide functional, hyperbranched polyesteramides have been tested in powder coating formulations together with stoichiometric (OH/COOH) amounts of acidic polyesters (Uralac). It was anticipated that the reaction of the hydroxyl end groups of the polyesteramide with the carboxylic acid end groups of the polyester would provide a well-crosslinked film with good mechanical properties by polymer/polymer cure. 

The dyeing of polypropylene fibers, being an item of research for decades, is successfully accomplished with partially stearate-modified hyperbranched polyesteramides. The long alkyl chains ensure compatibility with the polypropylene matrix. The mixing-in of hyperbranched polyesteramides via extrusion affected neither the melt spinning process nor the final polypropylene fiber properties. The modified fibers are dyeable under standard conditions as are, e.g., polyesters or cotton. They can even be used for printing for example a picture pattern on a polypropylene carpet. 

Our future research will lead to new types of hyperbranched polyesteramides. The ideas presented will enable properties such as water solubility (poly(ethyleneoxide) functional groups) or reduction of surface tension (fluoro-alkyl functionalized resins) to be precisely controlled. Last, but not least, mixed functional highly branched molecules with their (expected) unique set of combined properties have a huge potential to enter numerous technical fields. 

While all previous examples employ enzymatic ROP, there are two reports on block copolymer synthesis employing enzymatic poly condensation. The first one was published by Sharma et al. and describes the synthesis and solid-state properties of polyesteramides with poly(dimethylsiloxane) (PDMS) blocks [21]. The polycondensation was carried out with various ratios of dimethyl adipate. 

Seo [1997] prepared compatibilized PA blends with LCP polyesteramide (Hoechst Vectra B950) in the presence of anhydride-functionalized polyolefin. Specifically, 60 parts PA-6 was mixed with 25 parts LCP and 15 parts EPDM-g-MA in a TSE at 290°C. The blend was characterized by SEM, optical microscopy, Raman spectroscopy, mechanical properties, selective solvent extraction, and FTIR. 

At present, there is only one commercial source of the polyamide/polycarbonate blends (Dexcarb , Dexter Corp.). According to their patent, the blend was compatibilized by using a combination of a polyesteramide elastomer and a maleated olefinic polymer, such as male-ated polypropylene or EP rubber [Perron, 1984 1988]. However the degree or the efficiency of compatibilization achieved is unknown, since the added components are not known to be miscible or compatible with the polycarbonate. Nevertheless, the data sheet indicated good properties including a high notched Izod impact strength of > 700 J/m (Table 15.24). 

Chen, X. H. Zhong L. Jia J. Ling R. Tang J. Qiao Z. Zhang. Polyesteramides used for hot melt adhesives Synthesis and effect of inherent viscosity on properties. J. AppL Polym. Sci. 2001, 81, 2696-2701. 

AVEOOa] Averous L., Fauconner N., Moro L., et al, Blends of thermoplastic starch and polyesteramide processing and properties . Journal of Applied Polymer Science, vol. 76, no. 1, pp. 1117-1128,2000. 

It should also be mentioned that a combination of ester and amide linkages was frequently used to prepare thermotropic LC polyesteramides. Frequently, the inexpensive p-aminophenol is incorporated. For example, the Vectra B series is a poly(naph-thoate-aminophenolterephthalate) derived from 6-hydroxy-2-naphthoic acid (HNA), p-aminophenol, and terephthalic acid [14]. It is obvious that only a limited amount of p-aminophenol can be incorporated in order to maintain thermotropic liquid crystalline behavior. The amide linkage enhances the intermolecular interactions via hydrogen bridges and improves the solid state properties of the material. 

X. Liu, Y. Zou, G. Cao, D. Luo, The preparation and properties of biodegradable polyesteramide composites reinforced with nano-CaCOj and nano-SiO, Mater. Lett. 61 (2007) 4216-4221. 

Multilayer co-extrusion is another technique used in the preparation of starch/ synthetic sheets or films [164, 263-266], in which TPS is laminated with appropriate biodegradable polymers to improve the mechanical, water-resistance and gas-barrier properties of final products. These products have shown potential for applications such as food packaging and disposable product manufacture. Three-layer co-extrusion is most often practiced, in which a co-extrusion line consists of two single-screw extruders (one for the inner starch layer and the other for the outer polymer layers) a feedblock a coat-hanger-type sheet die and a three-roll calendering system [164]. Biodegradable polyesters such as PCL [164, 264], PLA [164, 263], and polyesteramide, PBSA and poly(hydroxybutyrate-co-valerate) [164] are often used for the outer layers. These new blends and composites are extending the utilization of starch-based materials into new value-added products. 

M. A. Elrehim, S. Said, A. Ghonerm and G. Turky, Dielectric properties of hyperbranched polyesteramide with long alkyl chain end groups , Macromol Symp, 2007,254,1-8. 

Danyadi L, Moczo J, Pukanszky B (2010) Effect of various surface modifications of wood flour on the properties of PPAvood composites. Compos A 41 199-206 Dash BN, Sarkar M, Rana AK, Mishra M, Mohanty AK, Tripathy SS (2002) A study on biodegradable composite prepared fi om jute felt and polyesteramide (BAK). J Reinf Plast Compos 21 1493-1503... 

Vapor-liquid equilibrium data of polyesteramide in water and ethanol Data extract from Landolt-Bornstein VIII/6D3 Polymers, Polymer Solutions, Physical Properties and their Relations I (Thermodynamic Properties Equilibria of Ternary Polymer Solutions) ... 

P02 values and tensile strength of polyamides and polyesteramides incorporating RDOA monomer suggest that there is a tremendous opportunity for development of high barrier packaging materials, considers Indspec. The lowest P02 values indicate that monolayer containers with high gas barrier properties can be made and used for preserving the taste of beer over an extended period of time, without further modifications. 

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