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A new bis(perfluorocyclohexane carbonyl) peroxide was prepared by the reaction of the corresponding acyl fluoride and hydrogen peroxide. This peroxide was applicable for the direct introduction of perfluorocyclohexyl group into various organic molecules such as acrylic acid oligomer, benzene and polystyrene; in particular interest, not only equatorial but also axial conformational isomers were isolated in phenylperfluorocyclohexane thus obtained.

New radical processes to obtain block and graft copolymers were developed by using special organic peroxides. Polymeric peroxides excelling in safety and solubility were newly prepared. PM 1 having OO bonds in its chain was prepared by polymerization of M 1 with polymeric peroxide, and M 2 was polymerized with PM 1 to provide PM 1 - b -PM 2 . A monomer having an OO bond was copolymerized with M 1 at a temperature below the decomposition temperature of the OO bond and PM 1 having pendant OO bonds was obtained. M 2 was addition-polymerized to pendant OO bonds to get PM 1 - g -PM 2 . Vinyl polymers having OO bonds were thermally mixed in an extruder with polyolefins and polyolefin- g -vinyl polymer was obtained by the reactive processing.

過酸化結合を側鎖に持つポリマーを混練機あるいは押出機を用いてポリオレフィンと溶融混和してポリオレフィンにグラフト化する反応を検討した. 過酸化結合を側鎖に持つポリマーは, 過酸化結合を持つモノマーを共重合させて合成した. 過酸化結合はランダムに導入しても効果なく, ブロックポリマーの一方のセグメント中に導入されたものであること, 及びこのセグメントが軟らかいポリマーであることが高グラフト化を達成するのに必要であった. アリルt-ブチルペルオキシカーポネート (AC) を用いて合成した酢ビ (VAc), スチレン (St) のブロックポリマーPoly (VAc, AC-b-St) (10/0.3/90wt) とポリオレフインとの等量混合物を混練機あるいは押出機中で, 180-230℃で溶融混練したときのグラフト効率を以下に示す. エチレン・酢ピコポリマー (EVA): 53%, 低密度ポリエチレン (LDPE): 17, 直鎖低密度ポリエチレン (LLDPE): 16, ポリプロピレン (PP): 10, エチレン・アクリル酸エチルコポリマー (EEA): 50.

過酸化ペルフルオロブチリル[1]の分解反応の詳細を研究した。[1]は対応する非フッ素化過酸化ジアシルにくらべラジカル分解を起こしやすいこと,また種々の求核剤の攻撃により容易に誘発分解を受けることを見いだした。

Kinetical studies and products analyses of the thermal decomposition of t-butyl heptafluoroperoxybutyrate (TBH) in benzene, octane, nitrobenzene, pyridine, and methoxybenzene have been carried out. In benzene and octane, the decomposition appears to be entirely a radical process. In nitrobenzene and pyridine, the reactions are found to give ionic decomposition products exclusively. On the other hand, the decomposition of TBH in methoxybenzene is characteristic of mixed ionic and radical cleavages.

Bis(heptafluorobutyryl) peroxide (1) smoothly reacted with furans and thiophenes under mild conditions to regioselectively give 2-perfluoropropylfurans and thiophenes in high yields. Mechanistically, reactions with furans or thiophenes are considered to be initiated by one-electron transfers from substrates to 1. On the other hand, the perfluoropropylation of pyridine was proceeded by the usual free-radical substitution to a pyridinium salt by a heptafluoropropyl radical produced by the homolytic decomposition of 1.

Various methacrylic esters with and without hetero atoms in their pendant ester groups were polymerized in toluene or in THF at −78°C using n-BuLi LiAlH4, or i-BuMgBr as an initiator. By comparing the isotacticities of the resultant polymers using the NMR spectral method, the influence of the hetero atom in the pendant ester group of the monomer on polymer stereoregularity was clarified. The experiments showed that the isotacticities of those polymers containing nitrogen or oxygen atoms in their side chains were lower than the isotacticites of those not containing such atoms. On the basis of these results the assumption was made that such depressing effects in isotactic propagation were caused by Lewis basicity of the nitrogen or oxygen atoms in the pendant ester groups. Furthermore, the effect of THF added to the polymerization reaction mixture, the effects of monomer concentration, the number of carbon atoms between the hetero atom and ester oxygen, and of the counter cation, all substantiated this assumption. The effect of hetero atoms on the syndiotacticities of the resultant polymers was also briefly studied.

The tacticities of poly(glycidyl methacrylate) prepared by radical polymerization at temperatures in the range from −78 to 60°C in several solvents or in bulk are described. The redox system diisopropylperoxy dicarbonate/dimethylaniline was found to polymerize this monomer effectively even at low temperature. The tacticities were determined by NMR spectroscopy. The difference of entropy Δ(ΔS1 ) and enthalpy Δ(ΔH1) of activation between isotactic and syndiotactic propagations were calculated. The values of Δ(ΔH1) were found not to be affected essentially by polymerization conditions and to be slightly larger than that of methyl methacrylate polymerization. Die Taktizitaten von Poly(glycidylmethacrylaten), die radikalisch im Temperaturbereich von −78 bis 60°C in einigen Losungsmitteln und in Substanz polymerisiert wurden werden beschrieben. Selbst bei niedrigerer Temperatur ist das Redoxsystem Diisopropylperoxydicarbonat/Dimethylanilin beim Monomeren wirksam. Die Taktizitaten der Polymeren werden mittels NMR-Spektren bestimmt. Die Entropie- und Enthalpiedifferenzen der Aktivierung des isotaktischen und syndiotaktischen Wachstums (Δ(ΔS1) bzw. Δ(ΔH1)) werden berechnet. Die Werte fur Δ(ΔH1) werden durch die Polymerisationsbedingungen nicht merkbar beeinflust und sind etwas groser als jene fur die Methacrylsauremethylesterpolymerisation.

Bis(heptafluorobutyryl) peroxide could be used as a reagent for perfluoropropylation of aromatic compounds under mild conditions.

The decomposition of t-butyl heptafluoroperoxybutyrate (TBH) was studied in both toluene and methanol. Kinetic and product studies from the thermolysis showed that this peroxy ester decomposes heterolytically in nonpolar solvents like toluene with homolysis, whereas in methanol this peroxy ester undergoes principally transesterification.

Bis(heptafluorobutyryl) peroxide could be used as a reagent for perfluoropropylation of aromatic compounds under mild conditions.