Block, ester-ether type

The oxidation of enol ethers and their derivatives is a useful method for the synthesis of a-hydroxy-ketones or their derivatives, which are versatile building blocks for organic synthesis. Since enol ethers and esters are types of olefin, some asymmetric epoxidation and dihydroxylation reactions have been applied to their oxidation. 

In ram extrusion experiments, the pressure is applied directly to the semicrystalline billet by use of a piston. Ram extrusion was used by Imada and coworkers for the extrusion of PP andofHDPE landfortheo3extrusionofHDPE withn-paraffins. Figure 1 gives a scfaematical representation of the apparatus used for ram extrusion. To decrease the friction of the Wllet during the extrusion experiment, a luMcant was added. A similar technique, however without lubricant, was applied for the solid-state extrusion of ther-mi lastic elastomers of the block copoly(ether ester) type by Droscher and co-workers ... 

Applications.—Reviews on the applications of polyesters in diverse fields have appeared with weathering performance of reinforced polyesters in building, water-soluble polyester resins with a polyfunctional aromatic acid base, poly(ester-ether) block copolymers - a new type of thermoplastic elastomer, improved polyester radial tyre yam with potential material, pollution, and energy saving,and a thermoplastic polyester review. ... 

In the simplest procedure (used, for example, for the synthesis of the block poly(ether ester)s already mentioned), a mixture of two reactants of similar chemical type, one being of low MW and the other oligomeric, is combined with a common co-reactant Rb used in stoichiometric equivalence to the total of reactive groups in P and R. The product (10) is a multiblock copolymer composed of two types of units, one of which includes the structural residue of the starting oligomer their relative proportions are determined by the values of x and y which can be varied at will, but their placement along the chain is statistical. The following relationships are important in relation to the bulk properties of such copolymers. 

The work reported here is concerned with the syntheses and properties of polyether-ester block copolymers containing poly (tetramethylene ether) units of molecular weight of approximately 1000 as the amorphous polyether blocks and a variety of esters as the crystallizable hard segments. The purpose of this study is to correlate changes in synthesis and properties of these thermoplastic and elastomeric copolymers with changes in the concentration and nature of the ester segments, particularly the types of diol and diacid. 

Isoprene is a hydrocarbon and is the basic building block of many essential oils, either in the form of a terpene or in an oxygenated form (e.g., alcohol, aldehyde, etc.). The components of an essential oil can be roughly classed into the following types terpenes (monoterpenes and sequiterpenes), oxygenated compounds, alcohols, phenols, aldehydes, ketones, esters, lactones, coumarins, ethers, and oxides. 

The explosion of interest in dendrimer chemistry over recent years has generated a huge range of dendritic architectmes, making them ripe for exploitation in the areas of nanochemistry and self-assembly. The most widely used dendritic systems rely on amide, ester and ether connectivities, primarily as a consequence of the synthetic simphcity of introducing branched building blocks via the formation of these types of bonds. (It is important that reactions used in dendrimer synthesis are particularly robust.)... 

Protein-based surfactants are usually synthesized with amino acids/peptides and fatty acids as building blocks. They are mainly of two types peptide and amino acid surfactants. Both are interesting compounds that contain an amino or a peptide as the hydrophilic part and a long hydrocarbon chain as the hydrophobic portion. The hydrocarbon chain can be introduced through acyl, ester, amide, alkyl, or ether linkage. Protein-based surfactants are usually con-... 

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