Patch acrylates

Perhaps a more specialized case of using plasticizers in acrylic formulations can be found in drug delivery patches. Here, plasticizing additives called excipients... 

Chlorinated rubber floor paints are probably the most common of the lower-cost floor paints on the market. They produce tough and chemically resistant coatings, but their adhesion to concrete is not always good. They tend to wear off in patches and cannot be considered as a durable floor treatment except under light traffic conditions. However, re-coating is a simple job and floors can easily be repainted over weekend shutdowns, for example. Similar paints based on other resins such as acrylics, vinyls and styrene butadiene are also used. 

In one report, a woman with dermatitis from the plastic nose pads of her spectacle frames was found on patch testing to react to 1% butyl acrylate but not to ethyl or methyl acrylate. The sensitization was attributed to butyl acrylate, which might have been present in the plastic nose pads. 

Sensitization to 2-hydroxypropyl acrylate during routine patch testing has been reported. ... 

Kanerva L, Estlander T, Jolanki R Sensitization to patch test acrylates. Contact Derm 18(1) 10-5, 1988... 

A host of bioadhesive controlled release systems have been proposed in recent years. Among the most commonly studied applications of bioadhesive materials is the area of buccal controlled delivery [408], The buccal delivery of small peptides from bioadhesive polymers was studied by Bodde and coworkers [409], and a wide range of compositions based on poly(butyl acrylate) and/or poly(acrylic acid) gave satisfactory performance. Bioadhesive poly(acrylic add)-based formulations have also been used for oral applications [402,410] for the sustained delivery of chlorothiazide [410] and for a thin bioadhesive patch for treatment of gingivitis and periodontal disease [411]. Other bioadhesive applications of polyelectrolytes include materials for ophthalmic vehicles [412,413], and systems for oral [410,414,415-419], rectal [420,421] vaginal [422] and nasal [423] drug delivery. 

On-aircraft repairs of composite using a rapid-cure resin system of composite component with UV light irradiation based on TRI patenP have been developed by the U.S. Air Force Research Laboratory. Alternating layers of the acrylate-based resin system and woven fiberglass (the widely used wet la)mp procedure) are applied to fill the hole and form a UV curable composition. The width of the patch can be up to 2 ft (0.6 m) and the depth as much as 0.2 in. (5 mm). The cure time using a 400 W UVA lamp is reported to be 20 min. Although it is essentially a depot repair, it can be done field when necessary to return an aircraft to service. Because of the necessity to cure relatively thick repair patches, Us-acylphosphine oxide was used as a photoinitiator. An example of the patented UV curable resin system used for the repairs is in Table 11.1. 

Adhesive polymers used in oral patches include poly(hydroxyethylcellulose), poly (hydroxypropylcellulose), poly(sodium carboxymethylcellulose), poly(acrylic acid), poly(methacrylic acid), polyvinylpyrrolidone) and poly (vinyl alcohol). 

CombiPatch is a three- or four-day patch that delivers both estradiol and norethin-drone acetate. CombiPatch is available in two sizes a 9-cm2 patch that delivers 0.05 mg of estradiol per day and 0.14 mg of norethindrone acetate per day and a 16-cm2 patch that delivers 0.05 mg of estradiol per day and 0.25 mg of norethindrone acetate per day. Estradiol is a lipophilic compound with a molecular weight of 272. The molecular weight of norethindrone acetate is 340. The design of the patch is considered an adhesive-matrix-type patch that consists of three layers. The backing is comprised of polyolefin and the adhesive layer contains a silicone adhesive, acrylate adhesive, estradiol, norethindrone acetate, oleic acid, and oleyl alcohol. 

Figure 12.2 SOFeX depth profiles of biomass (PN)-specific NO/ uptake rates, determined during 24-h incubations in Plexiglas acrylic incubators under simulated in-situ light and temperature conditions. Ultra-clean trace-metal techniques were used for sample collection within and outside (control waters) of the Fe-enriched patch north and south of the Antarctic Polar Front zone. The/-values [f = Fn03/(1 n03 + 1 nH4 + F n02 + F Urea)] were determined at the isolume depths of 47 and 16% surface irradiance, using tracer-level isotopic enrichments, and are not corrected for the effects of isotopic dilution. Error bars represent the range of duplicate samples (n = 2). Corrected from Coale et al. (2004).

Acrylic polymer concrete and mortars fast curing good chemical properties patch repairs... 

If conditions are severe, for example if there is widespread spalling and corrosion, patch repairs are carried out, followed by application of acrylic coating as the final part of the repair. Surface treatment with a silane... 

Okabe, H., Takayama, K., and Nagai, T. (1992). Percutaneous absorption of ketoprofen from acrylic gel patches containing D-limonene and ethanol as absorption enhancers, Chem. Pharm. Bull, 40 1906-1910. 

Uses Acrylic, wet adhesion modifier in Portland cement-based construction compds. (mortars, surfacers, patching compds.) binder for architectural coatings... 

The chamber test is a routine method of patch testing for contact allergy, but it can also be used to study NIICRs. The test substances are applied in small aluminum chambers (Finn Chamber, Epitest Ltd, Hyryla, Finland) and fixed to the skin with porous acrylic tape. The occlusion time is 15 min and the test is read at 20, 40 and 60 min. Occlusion enhances percutaneous penetration and may increase the sensitivity of the test. The advantage of the chamber test is that a smaller skin area is needed than in the open test (Lahti 1980 Hannuksela 1995). 

Hochman N, Ehrlich J, Zakay-Rones Z (1989) Oral cavity herpes simplex virus - a risk factor to dental personnel and patients (an overview). Isr J Dent Sci 2 2158-2161 Hytonen M, Vanhanen M, Keskinen H, Tuomi T, Tupasela O, Nordman H (1994) Pharyngeal edema caused by occupational exposure to ceUulase enzyme. Allergy 49 782-784 Kanerva L, Estlander T, Jolanki R, Pekkarinen E (1992) Occupational pharyngitis associated with allergic patch test reactions from acrylics. Allergy 47 571-573... 

Kanerva L, Henriks-Eckerman ML, Estlander T, et al. (1997b) Dentists occupational allergic paronychia and contact dermatitis caused by acrylics. Eur J Dermatol 7 177-180 Kanerva L, Henricks-Eckerman ML, Jolanki R, et al. (1997c) Plastics/acrylics material safety data sheets need to be improved. Clin Dermatol 15 533-546 Kanerva L, Jolanki R, Estlander T (i997d) Ten years of patch testing with the (meth)acrylate series. Contact Dermatitis 37 255-258... 

Dooms-Goossens (1995) has suggested the use of a semi-open test for testing patient-supplied products. Minute amounts (about 1-2 jiL) of the liquid product are applied with a cotton swab on an area (1 cm ) of the skin, allowed to dry completely, then covered with acrylate tape. The tape is removed after 2 days and read as ordinary patch tests. Dooms-Goossens has rarely seen very strong reactions using this technique. 

Contact sensitizers from a patient s own materials, such as formaldehyde, isothiazolinones, nickel, chromium, cobalt, colophony (in the form of resin acids), epoxy resin oligomers, reactive diluents, acrylates, methacrylates, polyamines and di-isocyanates, can be analyzed. In fact, any product can be analyzed, but it is not a routine task for laboratories and may be very expensive. There are two main reasons for chemical analyses. First, on patch testing, the patient is found to be allergic to a specific chemical, and the causative product(s) are analyzed for the chemical. Second, the patient s own material has caused an allergic test reaction, but MSDS or other information from the manufacturer did not reveal the causative chemical. In this case, it may be reasonable to analyze the material... 

Henriks-Eckerman M-L, Kanerva L (1997) Gas chromatographic and mass spectrometric purity analysis of acrylates and methacrylates used as patch test substances. Am J Contact Dermat 8 20-23... 

In general, a patch test concentration of 2% in petrolatum is recommended for the methacrylated monomers, and 0.1% in petrolatum for the acrylated monomers to avoid patch-test sensitization (Kanerva et al. 1988). 

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