Polyurethane Reactive diluent

A variety of polymers, both thermosets as well as thermoplastics, can be blended and coreacted with epoxy resins to provide for a specific set of desired properties. The most common of these are nitrile, phenolic, nylon, poly sulfide, and polyurethane resins. At high levels of additions these additives result in hybrid or alloyed systems with epoxy resins rather than just modifiers. They differ from reactive diluents in that they are higher-molecular weight-materials, are used at higher concentrations, and generally have less deleterious effect on the cured properties of the epoxy resin. 

Non-reactive diluent in epoxy or polyurethane systems Degreaser... 

Figure 4. Influence of the reactive diluent on the photopolymerization of a polyurethane-acrylate coating irradiated in the presence of air. [Irgacure 651] = 5% [Diluent] = 47 % Film thickness 24 pm.

For photocured polymer materials, the Persoz hardness was shown to depend mainly on the chemical structure of the prepolymer chain, on the functionality of the reactive diluent, on the photoinitiator system and on the duration of the UV exposure. The hardness of tack-free coatings thus continues to increase with further irradiation, as shown by Figure 6 for polyurethane-acrylates. This slow hardening process is likely to result from some further polymerization of the unreacted acrylic functions since their concentration was found to decrease concomittantly. 

The major application for epoxidized oils made by these means is their use as polyvinyl chloride (PVC)-plasticizers and stabilizers because of their ability to catch free HCl and slow degradation. Additionally, they can be used as reactive diluents for paints and as intermediates for polyurethane-polyol production. The most important product today is epoxidized soybean oil. The total worldwide production amounts to -200,000 t/y (4). 

Uses Reactive diluent for higher solids polyurethane coatings Features Ultra low vise, oxazolidine-based reduces VOC content in these systems, improves weathering performance Properties Clear to faint yish. liq., si. sweetish odor sol. in org. solvents, polyols m.w. 227 sp.gr. 0.955 dens. 8.08 Ib/gal vise. 30 cp vapor pressure 0.67 mm Hg (20 C) f.p. -32 C b.p. 127 C (15 mm Hg) flash pt. (PMCC) 93 C 100%... 

Uses Functional polyol for polyurethane industry for industrial/consumer RIM and structural polymers, dynamic elastomers, adhesives, binders, coatings, and sealants reactive diluent, dispersant for solvent coatings, etc. flexibilizerfor PU PU curative and crosslinker ManufJDistrib. Allchem Ind. BASF Bayer Huntsman Polyurethanes Witco... 

Toxicology Corrosive TSCA listed Storage Moisture-sensitive store under nitrogen Uses Reactive diluent used in high-solids two-component polyurethane coatings used as partial or total replacement for the polyol component, reduces VOC lowers vise., improves weathering performance Manuf/Distrib. Aldrich... 

Polyol, rigid Polyoxypropyleneamine Polyoxypropylene triol Uses Functional polyol for polyurethane industry for industrial/consumer RIM and structural polymers, dynamic elastomers, adhesives, binders, coatings, and sealants reactive diluent, dispersant for solvent coatings, etc. flexibilizer for PU PU curative and crossiinker Manuf./Distrib. Aiichem Ind. http //www.aiichem.com] BASF http //www.basf.com] Bayer http //www.bayerus.com] Huntsman Poiyurethanes http //www.icipu. com] http //www. rubinate. com Trade Name Synonyms Adeka Polyether PR-3007 [Asahi Denka Kogyo http //www.adk.co.jp]] Baycoll ND 1110 [Bayer/Fiber, Addits., Rubber http //www.bayerus.com]] Baycoll ND 2060 [Bayer/Fiber, Addits., Rubber http //www.bayerus.com]] Baycoll NT 1380 [Bayer/Fiber, Addits., Rubber http //www.bayerus.com]] Baycoll NT 5028 [Bayer/Fiber, Addits., Rubber http //WWW. bayerus. com]... 

Potassium ionisation of desorbed species (K IDS) with mass spectrometric detection is an extremely useful tool for the characterisation of high performance organic coatings. K IDS uses a commercial rapid heating probe to desorb intact molecules which are then ionised by potassium cation attachment. Based upon the molecular ions, which appear as [M]K, coatings components can be qualitatively and quantitatively analysed. In this work K IDS was selected as a method of soft ionisation, (i.e., producing molecular ions) because of its simplicity, wide applicability, low cost and compatibility with the quadrupole mass spectrometer. Simonsick [76] reports the application of K IDS to polymer additives (UV stabilisers and antioxidants), catalysts (organotin), reactive diluents (vernonia oil and aliphatic epoxides) and polyurethane precursors (polyesters and isocyanates). Tikuisis and co-workers [77] also discussed this technique. 

The disadvantages of epoxies include their two-component (or heat-cure) form, reduced performance on oily snrfaces, their inherent lack of toughness, and limited performance on thermoplastics reactive acrylics, cyanoacrylates and polyurethanes are usually superior in such departments. Also, the base resins are relatively high-molecular-weight species, so it is not possible to formulate very-low-viscosity adhesives unless reactive diluents are added, with a corresponding drop in performance. 

Multifunctional acrylates, unsaturated low-viscosity acrylic polyesters, and unsaturated polyurethanes or their mixtures only permit the formulation of solvent-free, photoreactive A-PSAs with desired viscosity (Figure 4.10). Data presented here is taken from a study, which, was done with three various UV-reactive diluents the selection of reactive diluents was made based on their solubility, photoreactivity, UV crosslinkability, and, if available, glass-transition temperature contribution. 

Diethylene glycol is reacted with adipic acid to manufacture polyester oligomers that are used in the manufacture of polyurethanes for various end uses. Both compounds are used in the manufacture of alkyds and as reactive diluents and crosslinking agents in coatings. 

A large range of reactive diluent products are now available for the modification of polyurethane coatings based on low viscosity castor oil derivates, oxazolidines, acetoacetate,and ketimines. In certain end uses, this approach offers compliant coatings with minor modification to existing formulations. 

Figure 10.1 Polymerization profiles recorded by RTIR spectroscopy upon UV exposure of an aliphatic polyurethane-acrylate (PUA) or an aromatic polyether-acrylate (PEA) in the presence of a monoacrylate or a diacrylate reactive diluent (25 wt%), respectively. Light intensity 40 mW cm . Laminated film.

Detailed data ate available, espedal in several di )ters of two edited books (1) and in a recent moncgraph (2). Few data are known on the photopolymerization itself and larged dqiend cn the prac famulatksi used as well as the experimental conditions. Typically, one photon absorbed can lead to 10000 polymerized double bonds (3). Rate constants of propagation fcp and termination fct for a polyurethane acrylate resin containing an acrylate monomer (weight ratio, 1 1) as reactive diluent are 10 1/mol/s and 3 x lO 1/mol/s respectively (when half of the double bonds have been polymerized) (3). 

A typical formulation of a photocurable composite resin contains four basic components a radical-type photo initiator, an acrylate functionalized oligomer, a reactive diluent and the clay mineral filler. The photoinitiator is usually an aromatic ketone which cleaves into two radical fragments upon UV exposure. The telechelic oligomer consists of a short polymer chain (polyurethane, polyether, polyester) end-capped by the very reactive acrylate double bond. An acrylate monomer is generally used as reactive diluent to reduce the resin viscosity. Figure 7.2 shows some typical compounds used in UV-curable acrylic resins. Different types of phyllosilicates were selected as mineral filler an organophilic clay (Nanomer I-30E from Nanocor), native hydrophilic clays (montmorillonite KIO and bentonite) and a synthetic clay (beidellite). 

Esters, ketones, and ether esters of polyurethane grade (i.e., absence of reactive constituents and a maximum water content of 0.05%) are required for solvent-containing paints. Aromatic hydrocarbons are suitable as diluents. High-solids two-pack paints containing 30-40 wt% of volatile components are becoming more popular on account of their low solvent emission. 

Chem. Descrip. Trimethylolpropane triethoxylate Uses Monomer, diluent for coatings, alkyds, polyurethanes Features Reactive... 

Allyl glyddyl ether is a monoglycidyl derivative, used as a reactive epoxy diluent for epoxy resins. As an impurity, it was considered as the sensitizing agent in a plastic industry worker allergic to 3-glycidyloxy-propyltrimethoxysilane, an epoxy silane compound used as a fixing additive in silicone and polyurethane. 

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