Journal Article

 

Purpose: In this experimental study, a sutureless scleral buckling was performed by using a tissue adhesive glue to fixate a silicone band to the sclera. In fact, one of the major risks of traditional scleral buckling is accidental perforation of the bulb, which is more frequent when the sclera is extremely thin as it is in newborns or in eyes with high myopia or scleromalacia.

New syntheses for neopentyl bromide and neopentyl chloride are reported which make these interesting aliphatic halides readily available in contraste to the previous methods used. These syntheses also provide unequivocal examples of reactions of the neopentyl-oxygen bond proceeding without rearrangement.

I-Adamantylmethyl 2-cyanoacrylate (1) was prepared by the reaction of 2-cyanoacryloyl chloride with 1-adamantylmethanol . 1,10-Decanediol bis-2-cyanoacrylate (2) was synthesized by transesterification of methyl 2-cyanoacrylate with 1,10-decanediol. Esters1 and2 were studied by X-ray structural analysis.

LE PROPRIETATES IMPERMEABILISATORI DE 2-CYANOACRYLATO METHYLIC USATE COMO AGENTE ADHESIVE IN LE DENTISTERIA.—Le proprietates impermeabilisatori de adhesive 2-cyanoacrylato methylic esseva comparate con illos de varie materiales de cementation que es currentemente usate in le dentisteria. 2-cyanoacrylato methylic, cemento a phosphato de zinc, cemento a oxydo de zinc e eugenol, e cemento Grip esseva usate in cementar applicatos plastic a platte superficies de 36 extrahite dentes human.

In order to study structure-tissue reactivity relationships and ultimately develop a less necrotizing adhesive, this laboratory undertook a study of the synthesis and degradation of the homologous series of α-cyanoacrylate monomers and polymers. A method for synthesizing high purity cyanoacrylates and some of their chemical and physical properties and presented. In vitro kinetics studies under heterotgeneous and homogeneous conditions indicate that cyanoacrylate polymers degrade by hydrolytic scission of the polymer chain.

A series of alkyl 2-cyanoacryloyl glycolate tissue adhesives were synthesized and characterized by NMR. Physical properties and bond strengths are presented. Within the series, bond strength decreased with increasing molecular weight. Corresponding polymers were evaluated by in vitro and in vivo techniques for biocompatibility. In general, in vitro biocompatibility increased with molecular weight.

Ethoxyethyl α-cyanoacrylate was synthesized by first making oligo(ethoxyethyl α-cyanoacrylate) through a condensation reaction of ethoxyethyl cyanoacetate with paraformaldehyde, followed by a depolymerization of the oligomer at an elevated temperature in an acidic atmosphere with a high vacuum. The ethoxyethyl cyanoacetate was in turn synthesized from an esterification of ethoxyethanol and cyanoacetic acid. The molecular structure of the target monomer and the corresponding intermediates were corroborated by IR and 1H-NMR.

The adhesive bond of allyl 2-cyanoacrylate between steel substrates has been analyzed and compared to that of ethyl 2-cyanoacrylate. Mechanical strength as well as thermomechanical, calorimetric, thermogravimetric, and dynamic mechanical response was observed. It was demonstrated that the allyl 2-cyanoacrylate bonds exhibit improved temperature resistance owing to the formation of heat-induced crosslinks in the adhesive layer, resulting in much improved lap-shear strengths.

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