Dimer acid modifiers

Pripol dimer acid modifying agents Unichema... 

A scan of the literature over the years 1980—1991 shows that most of the current dimer activity iavolves the reaction of dimer acids to form a huge variety of polyamide and polyester stmctures to modify their properties for a wide range of iadustries and uses. Many of these property modifications seem to make use of the flexihili ing properties or adhesion-promoting properties of the dimer stmcture. 

The most important coating appHcation for the nonreactive polyamide resins is in producing thixotropy. Typical coating resins such as alkyds, modified alkyds, natural and synthetic ester oils, varnishes, and natural vegetable oils can be made thixotropic by the addition of dimer acid-based polyamide resins (see Alkyd resins). Specialty high performance coating appHcations often requite the properties imparted by dimer acid components. 

Oleochemical based dicarboxylic acids - azelaic, sebacic, and dimer acid (Figs. 4.5 and 4.6) - amount to ca. 100000 tonnes year-1 as components for polymers. This is about 0.5% of the total dicarboxylic acid market for this application, where phthalic and terephthalic acids represent 87%. The chemical nature of these oleochemical derived dicarboxylic acids can alter or modify condensation polymers, and, used as a co-monomer, will remain a special niche market area. Some of these special properties are elasticity, flexibility, high impact strength, hydrolytic... 

Heloxy Modifier 71 390-470 400-900 Dimer acid diglycidyl ester provides flexilbility, improved impact strength and toughness when used as an additive Resolution... 

Fig. 15. Viscoelastic behavior of isocyanurate-oxazoiidone resins51). DEN 431 (polyglycidyl ether of phenol-formaldehyde novolac Dow Chemical Co.), EP 4080 (2,2-bis[p-(2,3-epoxypropyloxy)cyclo-hexane]propane Asahi Denka, Ltd.), EP 871 (diglycidyl ester of linoleic dimer acid Shell Chemical Co.), and L-MDI (modified diphenylmethane-4,4 -diisocyanate Desmodur CD Bater AG)...

PripoL [Unidiema Unichema Fnmce SA] Dimer ro trimer acids modifier fro nylon, polyester fibros used in polyamide for hot melt adhesives, ther-mogrs diic inks, urethane elastomers, industrial lubriemts, fuel additives, surface coatiiig reshfi, qun finishes. 

Chem. Descrip. Dimer acid-based polyester polyol Uses Modifier (increases flexibility, impact resist., toughness, hydrolytic stability) for industrial coatings (automotive, coil, textile, leather, wood lacquers) building block for PU elastomers, primers, sealants, elastic coatings... 

The most common application of vegetable oil-modified polyamides is in the surface coatings and paints industry. The dimer acids of tall and soybean oils and amines are used to modify the flow behaviour of paints. This thixotropic flow prevents setting and sagging, enables easy application and improves surface appearance. Vegetable oil-based nylons are used as engineering polymers in the automotive and transport industry for fuel lines. Products are also used for the extruded and moulded components of fuel systems such as filler necks, gas tanks, reservoir modules, filters, fuel rails and vapour recovery systems. Nylon 11 is also used in power coatings to coat metals that must withstand abrasion, impact and corrosion. 

Dimer acids and their derivatives, dimer diol and dimethyldimerate, are long-chain polymer grade fatty acids which act as good modifiers for condensation polymers. High amounts of aromatic structure and linear structure increase hardness and impact properties, respectively. They can be used to modify... 

Polyamide-modified alkyds are nsed as thixotropic agents to increase the low shear viscosity of alkyd resin based paints. Topically, abont 10% of a polyamide resin made from diamines snch as 1,2-ethanediamine (ethylenediamine) with dimer acids is reacted with an alkyd resin. High sohds thixotropic alkyds based on polyamides made with aromatic diamines have been developed, which give superior performance in high sohds alkyd coatings (36). 

El Pray M and Slonecki J (1999) Dimer fatty acid-modified poly [ester-6-ether]s. Synthesis and properties, Polym-Plast Technol Eng 38 51-69. 

The following resins or binders based on RR are used drying oils, - oleoresins, (modified)- ro-sin, rosin soaps, ->alkyd resins, ->shellac, chlorinated and cyclized - rubber, ->polyamides based on dimer acid and, - cellulose nitrate and - ethyl-cellulose. 

Trimethylsilyl esters of tris(thio)phosphonic acids 2070 are readily oxidized by DMSO in toluene at -30 °C to give the dimeric tetra(thia)diaphosphorinanes 2071 and HMDSO 7 [208] (cf. also the oxidation of silylated thiophenol via 2055 to diphenyl disulfide). The polymeric Se02 is depolymerized and activated by reaction with trimethylsilyl polyphosphate 195 to give the corresponding modified polymer... 

It would be ideal if the asymmetric addition could be done without a protecting group for ketone 36 and if the required amount of acetylene 37 would be closer to 1 equiv. Uthium acetylide is too basic for using the non-protected ketone 36, we need to reduce the nucleophile s basicity to accommodate the acidity of aniline protons in 36. At the same time, we started to understand the mechanism of lithium acetylide addition. As we will discuss in detail later, formation of the cubic dimer of the 1 1 complex of lithium cyclopropylacetylide and lithium alkoxide of the chiral modifier3 was the reason for the high enantiomeric excess. However, due to the nature of the stable and rigid dimeric complex, 2 equiv of lithium acetylide and 2 equiv of the lithium salt of chiral modifier were required for the high enantiomeric excess. Therefore, our requirements for a suitable metal were to provide (i) suitable nucleophilicity (ii) weaker basicity, which would be... 

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