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Monomer trimethylolpropane

Also, free radieal photoinitiation of polymerization of multifunctional acrylate monomers (trimethylolpropane triacrylate and phthalic diglycol diacrylate) was reported to take place by a cationic cyanine dye-borate eomplex 1,3,3, r,3, 3 —hexamethyl-11 -chloro-10,12-propylene tricarbocyanine friphenyl-butyl borate. The dye-borate complex was illustrated as follows ... [Pg.87]

Polyols. Several important polyhydric alcohols or polyols are made from formaldehyde. The principal ones include pentaerythritol, made from acetaldehyde and formaldehyde trimethylolpropane, made from -butyraldehyde and formaldehyde and neopentyl glycol, made from isobutyraldehyde and formaldehyde. These polyols find use in the alkyd resin (qv) and synthetic lubricants markets. Pentaerythritol [115-77-5] is also used to produce rosin/tall oil esters and explosives (pentaerythritol tetranitrate). Trimethylolpropane [77-99-6] is also used in urethane coatings, polyurethane foams, and multiftmctional monomers. Neopentyl glycol [126-30-7] finds use in plastics produced from unsaturated polyester resins and in coatings based on saturated polyesters. [Pg.497]

Photopolymerizable compositions based on monomeric acryflc or other ethylenicaHy unsaturated acid derivatives are becoming increasingly popular. When multiftmctional derivatives are employed, three-dimensional networks having high strength and abrasion resistance are possible on exposure to light. A typical composition may contain an ethoxylated trimethylolpropane triacrylate monomer, a perester phenacjhdene initiator (69), and an acryflc acid—alkyl methacrylate copolymer as binder. [Pg.44]

This has led to chemical modification of the polyesters, in particular the introduction of allyl ether groups into the resins. Amongst the monomers figuring prominently in the literature are allyl glyceryl ether I, trimethylolpropane diallyl ether II (1,1-diallyloxypropanol) and pentaerythritol triallyl ether III (2,2,2-trial-lyloxyethanol), as shown in Figure 25.32. [Pg.742]

The polymers were prepared using MAA as functional monomer and EDMA as crosslinking monomer if not otherwise noted. VPY= 2- or 4-vinylpyridine TRIM = trimethylolpropane trimethacrylate DPGE = (R)-N,0-dimethacryloylphenylglycinol PYAA = 3-(4-pyridinyl)acrylic acid. [Pg.156]

Polyurethanes are thermoset polymers formed from di-isocyanates and poly functional compounds containing numerous hydroxy-groups. Typically the starting materials are themselves polymeric, but comprise relatively few monomer units in the molecule. Low relative molar mass species of this kind are known generally as oligomers. Typical oligomers for the preparation of polyurethanes are polyesters and poly ethers. These are usually prepared to include a small proportion of monomeric trifunctional hydroxy compounds, such as trimethylolpropane, in the backbone, so that they contain pendant hydroxyls which act as the sites of crosslinking. A number of different diisocyanates are used commercially typical examples are shown in Table 1.2. [Pg.16]

FIGURE 31.8 Change in the coefficient of friction of modified dicumyl peroxide/ethylene-propylene-diene monomer (DCPD/EPDM) with the concentration of trimethylolpropane triacrylate (TMPTA) at a fixed irradiation dose of 100 kGy. (G) Surface modified with 100 kGy, (A) Bulk modified with 100 kGy dose, ( ) Control EPDM rubber. (Erom Sen Majumder, P. and Bhowmick, A.K., Wear, 221, 15, 1998. With permission.)... [Pg.890]

Real-Time FTIR. For our IR studies, we utilized a stoichiometrically equivalent amount of a trifunctional thiol, trimethylolpropane tris(2-mercaptoacetate), with a difunctional allyl, trimethylolpropane diallyl ether. The thiols were protected from oxidative polymerization by the addition of hydroquinone. The monomers and hydroquinone were purchased from Aldrich Chemicals and were used as received. This formulation was mixed for five minutes and then a commercial photoinitiator, Esacure TZT (Sartomer Inc.), which contained a blend of methyl benzophenones, was added at a level of 1.0% by weight of monomers to the formulation. Stirring was maintained for a further five minutes following the addition of the photoinitiator. The final formulation contained 2.0% by weight of hydroquinone. The samples were prepared prior to each experiment in order to ensure reproducibility of sample history. [Pg.155]

Thus, a semilogarithmic plot of the gel time as a function of 1/T should be linear, with the slope corresponding to the apparent activation energy. We have determined the gel times for a temperature range of 25°-50° C for a thiol-ene system consisting of stoichiometrically equivalent amounts of a trifunctional thiol, trimethylolpropane tris(2-mercaptoacetate), and a trifiinctional allyl monomer, triallyl isocyanurate. In this system, we also added 0.31% by weight of hydroquinone, to prevent premature polymerization, and 1.0% by weight of a commercial photoinitiator, Esacure TZT. [Pg.161]

Fig. 21. Molecular imprinting of (R)-propranolol using methacrylic acid (MAA) as the functional monomer and trimethylolpropane trimethacrylate (TRIM) as the crosslinking monomer. (Reprinted with permission from [126], Copyright 1998 Elsevier). The enantiose-lectivity of a given polymer is predetermined by the configuration of the ligand, R-propranolol present during its preparation. Since the imprinted enantiomer possesses a higher affinity for the polymer, the separation is obtained with a predictable elution order of the enantiomers... Fig. 21. Molecular imprinting of (R)-propranolol using methacrylic acid (MAA) as the functional monomer and trimethylolpropane trimethacrylate (TRIM) as the crosslinking monomer. (Reprinted with permission from [126], Copyright 1998 Elsevier). The enantiose-lectivity of a given polymer is predetermined by the configuration of the ligand, R-propranolol present during its preparation. Since the imprinted enantiomer possesses a higher affinity for the polymer, the separation is obtained with a predictable elution order of the enantiomers...
GAP is synthesized by replacing C-Cl bonds of polyepichlorohydrin with C-N3 bonds.The three nitrogen atoms of the N3 moiety are attached linearly with ionic and covalent bonds in every GAP monomer unit, as shown in Fig. 4.6. The bond energy of N3 is reported to be 378 kj mol per azide group. Since GAP is a liquid at room temperature, it is polymerized by allowing the terminal -OH groups to react with hexamethylene diisocyanate (HMDl) so as to formulate GAP copolymer, as shown in Fig. 4.7, and crosslinked with trimethylolpropane (TMP) as shown in Fig. 4.8. The physicochemical properhes of GAP prepolymer and GAP copolymer are shown in Table 4.4 and Table 4.5, respectively.I ]... [Pg.83]

Since BAMO polymer is a solid at room temperature, BAMO monomer is copolymerized with tetrahydrofuran (THF) in order to formulate a liquid BAMO copolymer that is used as a binder in propellants and explosives, as shown in Fig. 4.9. The terminal OH groups of the BAMO-THF copolymer are cured by reaction with the NCO groups of hexamethylene diisocyanate (HMDl) and then cross-linking is carried out with trimethylolpropane (TMP). The physical properties of such a copolymer with a BAMO/THF composition of 60/40 mol% are shown in Table 4.7.1151... [Pg.85]

The influence of adding polyfunctional monomers having different structures and functionality into a dicumyl peroxide-based crosslinking system for LDPE was investigated. Monomers employed were diallyl phthalate, trimethylolpropane trimethacrylate and triallyl cyanurate. The effects of formulation on matrix gel content and on foam density at similar gel content were examined and the dependence of foam density on melt modulus assessed. The applicability of swell ratio for estimating foam density was evaluated and the suitability of triallyl cyanurate as a crosslinking promoter for LDPE foam demonstrated. 20 refs. [Pg.38]

MIP films, applied to a QCM transducer, have been employed for chiral recognition of the R- and 5-propranolol enantiomers [107]. MIP films were prepared for that purpose by surface grafted photo-radical polymerization. First, a monolayer of 11-mercaptoundecanoic acid was self-assembled on a gold electrode of the quartz resonator. Then, a 2,2 -azobis(2-amidinopropane) hydrochloride initiator (AAPH), was attached to this monolayer. Subsequently, this surface-modified resonator was immersed in an ACN solution containing the MAA functional monomer, enantiomer template and trimethylolpropane trimethacrylate (TRIM) cross-linker. Next, the solution was irradiated with UV light for photopolymerization. The resulting MIP-coated resonator was used for enantioselective determination of the propranolol enantiomers under the batch [107] conditions and the FIA [107] conditions with an aqueous-ACN mixed solvent solution as the carrier. The MIP-QCM chemosensor was enantioselective to 5-propranolol at concentrations exceeding 0.38 mM [107]. [Pg.226]

Mosbach and co-workers developed a method to prepare molecularly imprinted polymers by precipitation polymerization [24]. They started from a dilute, homogenous solution of the monomer methacrylic acid (MAA) and the crosslinker trimethylolpropane trimethacrylate (TRIM) or ethylene glycol dimethacrylate (EGDMA). The polymer formed in the presence of the template molecule 17/1-estradiol, theophylline, or caffeine contained a high proportion of discrete spheres of diameter less than a micron. Because the effect of coalescence becomes predominant with higher solid content of the reaction mixture, this approach is limited to solid contents of typically <2 wt%. [Pg.129]

The effect of irradiation dose and different polyfunctional monomers(PFMs) at a constant ratio of 10 phr on the physicochemical properties of a PVC formulation used as wire coating was investigated. The PFMs used were trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, pentaerythritol tetraacrylate, triallyl cyanurate and 1,6-hexanediol diacrylate. The properties studied included tensile properties at room and elevated temps., softening temp., swelling characteristics and volume resistivity. 18 refs. [Pg.85]

Affinito [2] vapor coated hexanediol diacrylate, trimethylolpropane triacrylate, and tripropyleneglycol diacrylate hquid monomers at roughly 80°C and 1 X 10 torr onto polyethylene terephtholate and then radiation polymerized the surface using electron beam radiation. [Pg.122]

New photoreactive polymers with dimethylmaleimide side groups have been prepared, "" and co-polymers of methyl methacrylate with oligourethanes have tensile properties superior to those of the separate homopolymer systems."" New monomers have been prepared for fire-retardant u.v.-curable polymers " and trimethylolpropane has been photopolymerized in the vapour phase. Diphenylsulphoniumbis(methoxycarbonyl)methylide photoinitiates the polymerization of styrene and methyl methacrylate through the formation of... [Pg.484]

The template, the functional monomers and the cross-linking monomers are dissolved in a non-polar solvent. The functional monomers and the template form complexes and the strength of these are reflected in the selectivity of the imprinted polymer. The choice of functional monomer is based on the template structure. Functional monomers are chosen for their ability to interact non-covalently with the template molecule. The most frequently used functional monomer so far is methacrylic acid (MAA). Also vinylpyridines have been frequently used. As cross-linking monomers, ethyleneglycol dimethacrylate (EDMA) or trimethylolpropane trimethacrylate (TRIM) are widely used. Several other types of functional and cross-linking monomers have been used in molecular imprinting experiments using the non-covalent approach. The choice of monomers is of course important to the... [Pg.380]

An intriguing report by Steinke et al. [ 17] describes the creation of molecularly imprinted anisotropic polymer monoliths . Optically transparent blocks of MIP using either methacrylic acid (MAA) or 2-(acrylamido)-2-methylpropanesulphonic acid (AMPSA) as functional monomers and TRIM (trimethylolpropane trimethacrylate 2-ethyl-2-(hydroxymethyl)-l,3-propanediol trimethacrylate) as the cross-linker were synthesised using the photoactive template Michler s ketone... [Pg.468]


See other pages where Monomer trimethylolpropane is mentioned: [Pg.389]    [Pg.562]    [Pg.53]    [Pg.389]    [Pg.562]    [Pg.53]    [Pg.83]    [Pg.228]    [Pg.104]    [Pg.865]    [Pg.900]    [Pg.168]    [Pg.33]    [Pg.95]    [Pg.120]    [Pg.134]    [Pg.15]    [Pg.744]    [Pg.343]    [Pg.121]    [Pg.560]    [Pg.94]    [Pg.336]    [Pg.156]    [Pg.241]    [Pg.610]    [Pg.100]    [Pg.228]    [Pg.192]    [Pg.2022]   


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Trimethylolpropane

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