US 12,460,026 B2
Process for preparing fluoropolymers and fluoroelastomers in presence of a non fluorinated sulfonate type hydrocarbon containing surfactant thereof
Rajeev Chauhan, Bharuch (IN); Gaurav Kumar, Bharuch (IN); P. S. Rao, Bharuch (IN); Navin Soni, Bharuch (IN); B. S. Bhattacharya, Bharuch (IN); Anamika Dutta, Bharuch (IN); Akanksha Shukla, Bharuch (IN); and Anand Mohan Patel, Bharuch (IN)
Assigned to GUJARAT FLUOROCHEMICALS LIMITED, Noida (IN)
Appl. No. 17/767,103
Filed by GUJARAT FLUOROCHEMICALS LIMITED, Noida (IN)
PCT Filed Oct. 12, 2020, PCT No. PCT/IB2020/059569
§ 371(c)(1), (2) Date Apr. 7, 2022,
PCT Pub. No. WO2021/070159, PCT Pub. Date Apr. 15, 2021.
Claims priority of application No. 201911041309 (IN), filed on Oct. 11, 2019.
Prior Publication US 2022/0372179 A1, Nov. 24, 2022
Int. Cl. C08F 14/26 (2006.01); C08F 2/26 (2006.01)
CPC C08F 14/26 (2013.01) [C08F 2/26 (2013.01)] 5 Claims
 
1. A process for polymerizing fluoromonomer to fluoropolymer and/or fluoroelastomer in absence of fluorinated surfactants in an aqueous dispersion medium in presence of a non-fluorinated sulfonate type hydrocarbon surfactant comprised of 18 to 33 carbon atoms represented by formula (1):
with:
R1—[ArnXn-1]—(SO3M+)m   Formula (1)
R being an alkyl group comprised of a number of 15 to 20 carbon atoms;
l being the number of alkyl groups which varies from an integer from 1 to 2;
Ar being an aryl group;
n being an integer ranging from 1 to 2;
X being a bridging between aryl groups Ar, wherein the bridging is CH2 or linkage by either an ether or an amine function or group (C═O);
M+ being a monovalent cation comprised of hydrogen, an alkali metal, NH4+ or combinations thereof; and
m being an integer ranging from 1 to 2
wherein the process comprising the steps of;
a) forming an aqueous solution comprising stabilizing agent as paraffin wax, initial dose of non-fluorinated sulfonate type hydrocarbon surfactant along with redox system in a polymerization reactor, wherein redox system comprising oxidizing agents selected from ammonium persulfate (APS), potassium persulfate and potassium permanganate; and reducing agents selected from sodium sulfate, sodium bisulfate and oxalic acid;
b) pressurizing the polymerization reactor with fluoromonomers to form an aqueous dispersion;
c) initiating a polymerization reaction of the fluoromonomers by adding an initiator selected from disuccinic acid peroxide (DSAP), ammonium persulfate (APS) and combination thereof into the polymerization reactor;
d) propagation of polymerization reaction for growth of chain length of the fluoropolymer and/or fluoroelastomer by adding the surfactant metered into the polymerization reactor at a rate ranging between 0.01 g/(L*h) to 0.1 g/(L*h) during the polymerization reaction;
e) termination of the polymerization reaction after consumption of desired quantity of fluoromonomers with proviso that fluoropolymerization process is devoid of passivation of surfactant used.