	US 12,252,583 B2
	Method of making mixture of polymers
Giovanni Fontana, Paderno Dugnano (IT); Marco Galimberti, Bollate (IT); and Vito Tortelli, Milan (IT)
Assigned to SOLVAY SPECIALTY POLYMERS ITALY S.P.A., Bollate (IT)
Appl. No. 17/251,527
Filed by SOLVAY SPECIALTY POLYMERS ITALY S.P.A., Bollate (IT)
PCT Filed Jun. 19, 2019, PCT No. PCT/EP2019/066156 § 371(c)(1), (2) Date Dec. 11, 2020, PCT Pub. No. WO2019/243404, PCT Pub. Date Dec. 26, 2019.
Claims priority of application No. 18178902 (EP), filed on Jun. 20, 2018.
Prior Publication US 2021/0246264 A1, Aug. 12, 2021
Int. Cl. C08G 65/00 (2006.01); C08G 65/332 (2006.01)

CPC C08G 65/007 (2013.01) [C08G 65/3322 (2013.01); C08G 2650/48 (2013.01)]

7 Claims

1. A method for the synthesis of a mixture of polymers said polymers comprising a partially fluorinated polyether backbone possessing a plurality of recurring units including at least one cyclic group; said process comprising:

Step (I): a step of contacting:

at least one fluorinated compound comprising at least two acyl-fluoride groups; and

at least one hydrogenated compound comprising at least two fluoroformate groups of formula —CR_H¹R_H²—O—C(O)F, wherein each of R_H¹and R_H², equal to or different from each other at each occurrence, is independently H or a C1-C6 hydrocarbon group, in the presence of at least one fluoride-containing compound, wherein:

(i) at least one compound (F) is a compound (F_C) of formula:

F—C(═O)-Ef-Rcf-Ef-C(═O)—F

wherein:

each of Ef, equal to or different from each other, is a bond, or a divalent fluorocarbon group, possibly comprising one or more than one heteroatoms selected from Cl, N, O and S;

Rcf is a divalent fluorocarbon cyclic group, which may be a cycloaliphatic or a cycloaromatic group, which may comprise one or more than one cyclic moiety, and which may comprise one or more than one heteroatom included in the cycle, said heteroatom being selected from N, O and S;

and/or

(ii) at least one compound (H) is a compound (H_C) of formula:

F—C(═O)O—CR_H¹R_H²-EH_C-RH_C-EH_C-CR_H¹-R_H²—OC(═O)—F

wherein:

each of EH_Cis selected from a bond, a —O— group and a divalent linear or branched (oxy)alkylene group, wherein said (oxy)alkylene group comprises from 1 to 8 carbon atoms and is optionally interrupted by one or more than one ethereal oxygen atom;

RH_Cis divalent hydrocarbon cyclic group, which may be a cycloaliphatic or a cycloaromatic group, which may comprise one or more than one cyclic moiety, and which may comprise one or more than one heteroatom included in the cycle, said heteroatom being selected from N, O and S;

each of R_H¹and R_H², equal to or different from each other at each occurrence, is independently H or a C1-C6 hydrocarbon group;

to provide a polymer mixture (FH_cyclic);

Step (II):

heating said polymer (FH_cyclic) obtained in Step (I) at a temperature exceeding 120° C., for a duration of at least 4 hours and in the presence of a fluoride-containing compound comprising at least one of (i) a metal fluoride of formula MeF_y, with Me being a metal having y valence, y being 1 or 2, selected from the group consisting of NaF, CaF₂, AgF, RbF, CsF, KF, and combinations thereof; and (ii) an (alkyl)ammonium fluoride of formula NR^HN₄F, with each of R^HN, equal to or different from each other being, independently, a H or an alkyl group,

so effecting the thermolysis of at least a fraction of the chain ends of polymer (FH_cyclic) of formula —CR_H¹R_H²—OC(═O)F to groups —CR_H¹R_H²—F,

to provide polymer mixture (FH_{cyclic_CH2F});

Step (III^A):

reacting polymer mixture (FH_{cyclic_CH2F}) under esterification conditions in the presence of an alcohol of formula R_hOH, with R_hbeing a C₁-C₃hydrocarbon group; to provide for polymer mixture (FH_{cyclic_CH2F-ester/carbonate}), and then

Step (III):

fluorinating polymer mixture (FH_{cyclic_CH2F-ester/carbonate}) to provide for corresponding fluorinated polymer mixture (FF_{cyclic_CF3-ester/carbonate}).