Fluoroalkyl end-capped oligomers

In this chapter, we would like to review the recent development of preparation and applications of fluoropolymer nanocomposites by the use of fluoroalkyl end-capped oligomers as key intermediates. [Pg.59]

PREPARATION AND THERMAL STABILITY OF FLUOROALKYL END-CAPPED OLIGOMERS/SILICA NANOCOMPOSITES... [Pg.61]

PREPARATION AND PROPERTIES OF FLUOROALKYL END-CAPPED OLIGOMERS/TITANIUM OXIDE NANOCOMPOSTTES... [Pg.66]

Polyaniline (PAn)/inorganic composites have been considered as new class of materials due to their improved properties compared with those of pure conducting polymers and inorganic materials [73-77]. For example, the combination of electrical conductivity of PAn and UV sensitivity of anatase Ti02 are expected to find applications in electrochromic devices, nonlinear optical system, and photochemical devises [73], From this point of view, it is in particular interest to prepare fluoroalkyl end-capped oligomers/PAn/titanium oxide nanocomposites. In fact, fluoroalkyl end-capped acrylic acid oligomer [Rp—(ACA) —Rp]/, 2-methacryloyloxyethane sulfonic acid oligomer [Rp—(MES) —Rp]/, 2-acrylamido-2-methylpropanesulfonic acid... [Pg.69]

SCHEME 4.11 Preparation of fluoroalkyl end-capped oligomers/PAn nanocomposites. [Pg.69]

SCHEME 4.2 Synthesis of two fluoroalkyl end-capped acrylic acid oligomer by using fluoroalkanoyl peroxide. [Pg.60]

Fluoroalkyl end-capped A-(l,l-dimethyl-3-oxobutyl)acrylamide oligomer/silica nanocomposites [Rp—(DOBAA) —Rp/Si02l were prepared by the sol-gel reactions of the corresponding oligomer with tetraethoxysilane (TEOS) under alkaline conditions (see Scheme 4.5) [43 5]. [Pg.61]

SCHEME 4.5 Preparation of fluoroalkyl end-capped A -(l,l-dimethyl-3-oxobutylacrylamide) oligomers [Rp—(DOBAA) —Rpl/silica nanocomposites. [Pg.62]

Fluoroalkyl end-capped acrylic acid oligomer [Rp—(CH2CHCOOH) —Rp/Si02l [Rp—(ACA) —Rp]/silica nanocomposites decompose completely at 800°C to afford the weight loss in proportion to the content of Rp—(ACA) —Rp oligomer in composites due to the nonformation of ammonium hexafluorosihcate during the calcination... [Pg.64]

Fluoroalkyl end-capped acrylic acid oligomer [Rp—(ACA) —Rp] can also react with (TEOS) and silica nanoparticles in the presence of low molecular weight aromatic compounds [Ar—H] such as cetylpyridinium chloride (CPC) and bisphe-nol AF under alkaline conditions to afford Rp—(ACA) —Rp/Si02 nanocomposites-encapsulated Ar—H in excellent to moderate isolated yields (see Scheme 4.7) [49],... [Pg.64]

These fluorinated silica nanocomposites-encapsulated Ar—H can exhibit no weight loss behavior corresponding to the contents of Ar—H even after calcination at 800°C, although fluoroalkyl end-capped acrylic acid oligomer in the nanocomposites decomposed completely under similar conditions [49]. [Pg.64]

Novel cross-linked fluoroalkyl end-capped trimethoxyvinylsilane oligomeric nanoparticles [Rp—(VM-Si02) —Rp]-encapsulated l,l -bi(2-naphthol) (BINOL) were prepared by the sol-gel reaction of fluoroalkyl end-capped trimethoxyvinylsilane oligomer in the presence of BINOL under alkaline conditions (see Scheme 4.8) [50],... [Pg.65]

It is well-known that anatase transforms irreversibly to rutile at elevated temperatures [70]. Normally, the phase transformation temperature in air from anatase to rutile titanium oxide is between 600°C and 750°C [71]. From an applicable viewpoint of anatase titanium oxide into a variety of fields, it is deeply desirable to develop thermally stable anatase titanium oxide composites without the phase transformation to mtile under such higher temperature conditions. We have very recently found that fluoroalkyl end-capped vinyltrimethoxysilane oligomer/anatase titanium oxide nanocomposites [Rp—(VM—Si02) —RF/0 -TiO2] can keep completely its... [Pg.68]

Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...