Plant oil based polymers

This chapter surveys different process options to convert terpenes, plant oils, carbohydrates and lignocellulosic materials into valuable chemicals and polymers. Three different strategies of conversion processes integrated in a biorefinery scheme are proposed from biomass to bioproducts via degraded molecules , from platform molecules to bioproducts , and from biomass to bioproducts via new synthesis routes . Selected examples representative of the three options are given. Attention is focused on conversions based on one-pot reactions involving one or several catalytic steps that could be used to replace conventional synthetic routes developed for hydrocarbons. 

The shortage of oil and natural gas has been reflected in shortages and spiraling prices for polymers based on petrochemical resources. Providentially, such polymers may be in part replaced by lignocellulosic materials that are the most abundant and most economical organic renewable resources available. In their natural state as wood and plant fibers, and as the principal constituent used in the manufacture of paper, textile fibers, and many other industrial products, lignocellulosic materials will continue to be fundamental to human welfare. 

Materials can also be partly produced from plants such as oil-based plant fiber/polymer composites. The interest in plant fiber resides in their low cost, their low abrasiveness (toward implementation machineiy) and particularly their low toxicity compared with synthetic fibers, which are irritants to the respiratory tract [MOH 00], Hemp, hessian, sisal or flax are largely used in cars in Germany. During 2005, 3.5 kg of natural fibers were used per automobile passenger in Germaity, particularly in compression molded composite parts [MON 05]. 

Lu, J., Hong, C.K. and Wool, R.P. (2004) Bio-based nanocomposites from functionalized plant oils and layered silicate. Journal of Polymer Science, Part B Polymer Physics, 42(8), 1441-1450. 

As a possible application of glycerol-based polyesters, new crosshnkable polyesters were synthesized via a lipase CA-catalyzed polymerization of divinyl sebacate and glycerol, in the presence of unsaturated higher fatty acids derived from renewable plant oils [110, 111]. The curing of the polymer obtained from hnoleic or hnolenic acid proceeded via a cobalt naphthenate catalyst or thermal treatment to produce a crosshnked transparent fUm with good biodegradabiHty. 

J. Lu, C. K. Hong and R. P. Wool, Bio-based nanocomposites from functionalized plant oils and layered sUicate , J Polym Sci Part B Polym Phys, 2004, 42, 1441-50. 

There have been a number of studies dedicated to organically modified layered silicate reinforced completely biodegradable nanocomposites to target highly exfoliated structures. Renewable resources-based biodegradable polymers utilized so far for the preparation of nanocomposites are poly(lactic acid) (PLA) [40-68,11-15], poly(3-hydroxy butyrate) (PHB) [69,16-20] thermoplastic starch [71-77,21-25], plant oils [78-81,26-30], cellulose [82,83,30,31], etc. The following section deals with the transformation of the properties of renewable sources-based biodegradable polymers as their layered silicate nanocomposites. 

In the field of film-forming materials, use of alkyd resins incorporating plant oils or their derivatives has been a standard practice for a century, but no major qualitative advance was introduced imtil recently. The same applies for bulk polymers based on vegetable oils, of which linoleum (first commercialised in the middle of the 19 century) was for a long time the only important representative of these materials. Nylon 11 (commercialised under the name of Rilsan based on castor oil as a precursor) has been an important addition to this small family from the 1950s onwards. In other words, vegetable oils represented a very modest presence as basic constituents of macromolecular materials up to about a decade ago, but the situation has evolved radically since then. 

Applications include parts in airplane and automobile engines, chemical plants, oil and gas processing equipment, and steam processing equipment. Ketone-based polymers are used in high-temperature electrical and electronic applications and medical applications. Certain resins have been used as electrical coatings and in... 

ADMET has been used to take advantage of several natural polymer feedstocks, mainly plant oils and fatty acids (Figure 13.26) [190]. An initial study optimized the ADMET polymerization of a variety of plant oils, and yields of40—60% were obtained [191]. A set of polyamides were synthesized by ADMET polymerization of monomers ultimately derived from ricinoleic acid, the main fatty acid of castor oil [192]. Similarly, ADMET was utilized to polymerize 1,3-di-lO-undecenoxy-2-propanol, a castor oil-based diene, which was subsequently reacted with... 

The session Polymer from Biomass included 8 oral presentations. These presentations were devoted to the problems of production (synthesis) polymers from biomass particularly sustainability assessment of polymers based on renewable resources novel cellulose based materials and processing routes biomass-based polyesters and polycarbonates for coating and engineering plastic applications plant oils as renewable resources in polymer science. 

Warwel et al. applied catalytic methods of olefin chemistry to achieve polymer building blocks as well as polymers like functionalized polyolefins, polyesters, polyethers, polyamides as well as sugar-based surfactants [4]. The fundamental approach was the polymer synthesis based on unsaturated fatty acid methyl esters, which are available by industrially applied transesterification of fats and oils with methanol. In Figure 18 is reported a schematic representation of the potential of plant oil components in the preparation of different polymeric materials. 

Although plant oil-based polymers are mainly derived from soybean and castor oil, an ever increasing number of publications are devoted to the use of other plant oils, such as linseed oil, tung oil, canola oil, high oleic sunflower oil, and many others. 

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