Polyesters environmentally-friendly

Throughout the 1990s a large portion of the research and development effort for hot melt adhesives focused on developing adhesives that are either environmentally friendly or functional [69,81,82]. Environmentally friendly attributes include biodegradability, water dispersibility (repulpability), renewability, and water releasability. Biodegradable adhesives have been developed based on starch esters [83-86] and polyesters such as poly (hydroxy butyrate/hydroxy valerate) [87], poly(lactide) [88-91], and poly(hydroxy ether esters) [92-94]. All but the... 

Polyesters are now one of the economically most important classes of polymers, with an overall world production between 25 and 30 million tons in 2000, consisting mostly of PET. This production is rapidly increasing and is expected to continue to do so during the next decade, driven by packaging applications, due to a very favorable image of environmentally friendly and recyclable polymers in western countries, and by textile applications, due to a strong demand in the far-east area to satisfy the needs of an increasing population. 

Aliphatic polyesters occupy a key position in the field of polymer science because they exhibit the remarkable properties of biodegradability and biocompatibihty, which opens up a wide range of applications as environmentally friendly thermoplastics and biomaterials. Three different mechanisms of polymerization can be implemented to synthesize aliphatic polyesters (1) the ring-opening polymerization (ROP) of cyclic ketene acetals, (2) the step-growth polymerization of lactones, and (3) the ROP of lactones (Fig. 1). 

Keywords biodegradable, biobased, polyester, polylactide, mechanical properties, dispersion, environmentally friendly. 

Problem 22.34 Polylactic add (PLA) has received much recent attention because the lactic acid monomer [CH3CH(0H)C00H] from which it is made can be obtained from carbohydrates rather than petroleum. This makes PLA a more environmentally friendly polyester. (A more in-depth discussion of green polymer synthesis is presented in Section 30.8.) Draw the structure of PLA. 

Enzymatic polymerizations are a promising strategy under study by many groups throughout the world to develop environmental friendly processes for polyester synthesis. 

Breathable membrane producer Sympatex has also established a maximum ecology and sustainability approach in developing its product, Phaseable. It contains environmental friendly 100% solvent-free foam print and coating as well as recycled polyester face fabric. 

Chem. Descrip. Aluminum hydroxide CAS 21645-51-2 EINECS/ELINCS 244-492-7 Uses Filler, flame retardant for polyester resins (SMC, BMC, laminates, artificial marble), epoxy, acrylic, PU (flexible and rigid foam, castings), latexes (carpetbacking), crosslinked elastomers (cables, flooring), aq. disps., paints, varnishes, powd. coatings Properties Powd. 15-25 pm median particle size dens. 2.4 g/cc bulk dens. = 900 kg/m oil absorp. 18-22 cc/100 g brightness (TAPPI) = 90 ref. index 1.58 pH 9 1 conduct. < 120 pS/cm 99.6% act. Environmental Environmentally friendly Martinal ON-904 [Martinswerk GmbH Lonza]... 

Recently, various aliphatic polyesters have become known to be the environmentally friendly materials with biodegradable nature or from a nonpetroleum origin. For example, a copolymer type poly(hydroxyalkanoate), poly(3-hydroxybutyrate-C( -3-hydroxyvalerate) (P(3HB-co-3HV)), which is usually produced through the bacterial... 

Belonging to the family of aliphatic polyesters, poly(lactic acid) or polylactide (PLA) is composed of lactic acid repetitive units, which is the simplest ot-hydro)y acid with an asymmetric carbon atom. Interestingly, the L-lactic acid monomer, and more recently the D-lactic acid monomer, can be straightforwardly obtained by bacterial fermentation from renewable resources (namely starch), making both monomers and therefore the resulting polymers environmentally friendly. Polycondensation of lactic acid and ring-opening polymerization (ROP) of lactide (LA), i.e. cyclic diesters of lactic acid, are currently used to prepare PLA polymers (Scheme 4.1). 

Abstract The use of two environmentally friendly technologies, the plasma and laser approaches, in treating the surface of textiles is discussed in this chapter. The surface of fibrous materials can be functionalized and structured on the nano- and micro-scales, and the results of the treatment of natural and synthetic fibres such as wool, cotton, polypropylene, polyester and polyamide which have been treated by different plasmas and lasers are detailed and are found to be similar to morphological modification of a textile surface using the ripple/roll-structure technique. 

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