K. A. Mager

Silicon-containing esters of ?-cyanoacrylic acid: synthesis and properties

A number of cyanoacetates have been synthesized: cyanoacetoxymethyitrimethylsilane (1), cyanoacetoxymethylpentamethyldisiloxane (2), cyanoacetoxyetoxymethylpentamethyldisiloxane (3). They were converted by the Knoevenagel reaction to novel esters of a-cyanoacrylic acid (4–13) containing silicon atoms in the ester groups and having the general formula RCH=C(CN)COOCH2X (where R=H, 4-MeOC6H4, MeCH=CH, 2-furyl; X=SiMe3, SiMe2OSiMe3, CH2OCH2SiMe2OSiMe3). These compounds are capable of copolymerization with esters of cyanoacrylic acid which are the precursors to adhesives for cold curing.

A calorimetric study of ethyl-α-cyanoacrylate and its polymerization and a study of polyethyl-α-cyanoacrylate at 13-450 K and normal pressure

Precision adiabatic and isothermal calorimetry have been used to study the following thermodynamic properties of ethyl-α-cyanoacrylate and its polymer: the isobaric heat capacity of the monomer in the region 13–330 K and that of the polymer in the region 13–450 K; the thermodynamic parameters of the monomers physical transition, the parameters of the polymers glass-transition and the glassy state and the combustion energy of the monomer and polymer. The following thermodynamic functions have been calculated: H0(T) − H0(0); S0(T), G0(I) − H0(0); ΔHcom0, δHf0, ΔSf0 and ΔGf0. The data obtained have been used to calculate values of the enthalpy, entropy and the Gibbs function for the polymerization of ethyl-α-cyanoacrylate in the temperature range 0–450 K and to assess the upper limiting temperature for this process.

Synthesis of functionally substituted 2-cyanoacrylates

The conditions for the Knoevenagel synthesis of 2-cyanoacrylates containing double and triple bonds in the alkoxycarbonyl group have been studied. It was found that the esters are formed in 10–70 % yields by the condensation of the respective cyanoacetates with formaldehyde in the 1∶1 ratio in the presence of piperidine, followed by the pyrolysis of the oligomers formedin vacuo at 170–200 °C in the presence ofpara-toluenesulfonic acid. The compounds synthesized readily undergo polymerization at room temperature and can be used as the basis for thermostable rapidly polymerizing adhesives.

Synthesis of 2-cyanoacrylatesvia 2-cyanoacryloyl chloride

Monomers that are difficult to obtain, such as tert-butyl 2-cyanoacrylate, trimethylsilyl-methyl 2-cyanoacrylate, 2,2,3,3-tetrafluoropropyl 2-cyanoacrylate, and the previously unknown adamantyl 2-cyanoacrylate were prepared starting from 2-cyanoacryloyl chloride.

SYNTHESIS OF FUNCTIONALLY SUBSTITUTED CYANOACETATES

Some new cyanoacetates were synthesized and characterized. They are precursors for α-cyanoacrylates used as rapidly polymerized, cold-hardening adhesives.

Copolymers of dimethyl 2-methyl-1,3-butadienethiophosphonate with 1,1,2-trichloro-1,3-butadiene or ethyl α-cyanoacrylate☆

Abstract Dimethyl 2-methyl-1,3-butadienethiophosphonate was copolymerized radically with 1,1,2-trichloro-1,3-butadiene or with ethyl α-cyanoacrylate. IR and NMR spectra ( 1 H and 31 P) give evidence that polymerization of the phosphorus-containing monomer and, when it is present in excess, also its copolymerization proceeds largely as 3,4 polyaddition. Copolymers containing both phosphorus and chlorine exhibit a decreased flammability: the oxygen index varies between 21 and 45. Elastic films of high mechanical strength can be prepared by casting from solutions of the copolymers in chlorinated or aromatic hydrocarbons.

The thermodynamics of allyloxyethyl-α-cyanoacrylate, its polymerization and the polymer obtained at 0–330 K☆

Adiabatic and isothermal calorimetry have been used to study the thermodynamic properties of allyloxy-ethyl-α-cyanoacrylate and polyallyloxyethyl-α-cyanoacrylate and the following properties have been determined: the isobaric heat capacity of the monomer and the polymer in the range 11–330 K, the glass-transition parameters and the parameters of the glassy state of the monomer, the energy of combustion of the monomer and the polymer. The following thermodynamic functions have been calculated from the experimental data obtained: H0(T) − H0(0), S0(T) and G0(T) − H0(0) for the range 0–330 K, and the enthalpy of combustion and the thermodynamic parameters of formation, ΔHf0, ΔSf0 and ΔGf0. These results been used to calculate the enthalpy, entropy and the Gibbs function for the polymerization of allyloxyethyl-α-cyanoacrylate in bulk in the range 0–330 K and the upper limiting temperature for polymerization has been estimated.

Synthesis of adamantane monomers and their properties

ConclusionSyntheses were reported for new adamantane monomers, namely the allyl and propargyl esters of 1-adamantanecarboxylic acid, the diallyl and dipropargyl esters of 1,3-adamantanedicarboxylic acid and di-1-adamantyl maleate. These esters are capable of undergoing thermal copolymerization with α-cyanoacrylate esters.