摘要:
A method for removing a fluorinated carboxylic acid or salt thereof from an aqueous liquid by contacting the aqueous liquid with adsorbent particles. The fluorinated carboxylic acid or salt thereof is selected from the group consisting of partially fluorinated carboxylic acids or salts thereof and fully fluorinated carboxylic acids or salts thereof.
摘要:
The present disclosure describes fluoropolymers having long chain branches and methods of making these fluoropolymers. These fluoropolymers may have improved melt processing properties. Shaped articles containing these fluoropolymers are also provided.
摘要:
A method of making a fluoropolymer dispersion by first providing a fluoropolymer dispersion comprising fluoropolymer particles and one or more fluorinated surfactants selected from fluorinated carboxylic acids or salts thereof having the general formula: [Rf—O-L-COO−]iXi+ (I) wherein L represents a linear partially or fully fluorinated alkylene group or an aliphatic hydrocarbon group, Rf represents a linear partially or fully fluorinated aliphatic group or a linear partially or fully fluorinated aliphatic group interrupted with one or more oxygen atoms, Xi+ represents a cation having the valence i and i is 1, 2 or 3; Then adding one or more non-fluorinated surfactants selected from anionic and non-ionic surfactants followed by reducing the total amount of the one or more fluorinated surfactants to an amount of not more than 500 ppm, for example not more than 250 ppm based on the total weight of the dispersion while maintaining or increasing the amount of solids in the dispersion.
摘要:
In accordance with one aspect of the invention, there is provided (i) an amorphous fluoropolymer that has one or more cure site components, the cure site components being contained in the amorphous fluoropolymer in an amount between 0.1 and 0.5 mol % based on the total amount of repeating units and/or (ii) the amorphous fluoropolymer is capable of being dehydrofluorinated, wherein the amorphous fluoropolymer is derivable from a polymerization of (a) one or more gaseous fluorinated monomers and (b) not more than 0.5% by weight based on the total weight of monomers of one or more olefins having a bromine or iodine atom bonded to a carbon of the double bond of the olefin.
摘要:
A fluoropolymer having a reduced amount of polar end groups. The fluoropolymer is produced by free radical polymerization of fluorinated monomers and the initiation of the polymerization is carried out in the presence of a chloride salt. Polar end groups include hydroxy groups and ionized or ionizable end groups. Examples of ionized or ionizable end groups include acid groups and salts thereof such as sulfonic acid and salts thereof, —CH2—OSO3H groups, sulfates and carbonyl containing end groups such as carboxylic and carboxylate groups. Due to the presence of chloride salt at the initiation of the free radical polymerization, CF2Cl end groups are formed instead of the polar end groups. As a result, a fluoropolymer is obtained that has improved processibility and heat resistance.
摘要:
Emulsifier free fluoropolymer manufacturing method in which (a) a mixture of an oxidizing agent and reducing agent is used to start the polymerization and where one or the other but not both, are further added during polymerization, or (b) an oxidizing metal ion is added to start polymerization and where additional oxidizing metal ion is added during polymerization.
摘要:
Cured, latex-blended compositions featuring a fluoroelastomer and a fluoroplastic, and curable core-shell polymers having a fluoroelastomer precursor-containing shell and a fluoroplastic-containing core.
摘要:
Provided are a tetrafluoroethylene copolymers having a melting point of at least 317° C., a melt flow index (MFI) at 372° C. and a 5 kg load (MFI 372/5) of from about 0.60 g/10 min up to about 15 g/10 min. Also provided are methods of forming a shaped article using the copolymers described above, shaped articles made with those copolymers and compositions containing such copolymers.
摘要:
A composition comprising a first fluoropolymer and a second fluoropolymer. The first and second fluoropolymers are melt-processable, thermoplastic and have a melting point between 100° C. and 320° C. The first fluoropolymer has a relaxation exponent of from 0.93 to 1.0. The second fluoropolymer has a relaxation exponent of from 0.3 to 0.92. A composition comprising a first fluoropolymer having a long chain branching index of from 0 to 0.1 and a second fluoropolymer having a long chain branching index of at least 0.2. A composition comprising a core-shell polymer having a first polymer portion, wherein a polymer having an identical chemical structure as the first polymer portion has a relaxation exponent of from 0.93 to 1.0, and a second fluoropolymer portion, wherein a polymer having an identical chemical structure as the second fluoropolymer portion has a relaxation exponent of from 0.3 to 0.92. Methods for making compositions and methods of making articles from compositions.