Fluoro-Modified Polyurethanes

M.E. PENOFF; P.E. MONTEMARTINI; P.A. OYANGUREN

Los Cocos, Córdoba, Argentina

Simposio; V Simposio Argentino-Chileno de Polímeros; 2009

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin-top:1.0pt; margin-right:0cm; margin-bottom:0cm; margin-left:0cm; margin-bottom:.0001pt; text-align:justify; text-indent:14.2pt; mso-pagination:none; mso-layout-grid-align:none; punctuation-wrap:simple; text-autospace:none; font-size:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The wide applicability of polyurethanes (PUs) is due to versatility in selection of monomeric materials from a huge list of macrodiols, diisocyanates and chain extender (CE). The chemistry involved in the synthesis of PU is centered on the isocyanate reactions. Thermoplastic PU may be described as the linear structural block copolymer of (SH)n type, where S is soft segment (SS) and H is hard segment (HS). Properties of thermoplastic PU depend upon several factors such as the composition of SSs and HSs, lengths and length distribution of SS and HS chains, chemical nature of the units composing the polymer, molecular weight, morphology in the solid state, etc. Fluorine-containing polymeric materials exhibit unique property combinations of low surface energy, low friction, low refractive indices, dirt repellent, biological inertness, good resistance to corrosive chemicals, good stability against hydrolysis, low water and ion permeability, low solubility in polar and non-polar organic solvents (being non-wettable and oleophobic, low interfacial free energy) due to substancial hydrophobicity.  Thay also have remarkable resistance to flame, UV radiation, fouling agents and possess excellent thermal stability [1]. Fluorocarbon chains have been incorporated into PUs via fluoro-containing isocyanates [2], CEs [3] or SSs [4]. Fluoro-modified PUs offers significant advantages in applications where unusual bulk and surface properties are required. This approach allows one to design new structures depending on the extent of fluorine modification [1]. In this work we synthesize polyethylene glycol based thermoplastic polyuretahnes (PUs) and fluorinated thermoplastic polyuretanes (FPUs) employing  etanol-terminated perfluorochains, with the aim of comparing their properties.