Polymerization process in aqueous emulsion of fuluorinated olefinic monomers

• US 5,498,680 A
• Filed: 05/23/1995
• Issued: 03/12/1996
• Est. Priority Date: 05/18/1993
• Status: Expired due to Term

• Current Assignee: Ausimont, S.p.A. (Syensqo SA)
• Original Assignee: Ausimont, S.p.A. (Syensqo SA)
• Inventors: Abusleme, Julio A., Maccone, Patrizia
• Primary Examiner(s): Schofer, Joseph L.
• Assistant Examiner(s): SAROFIM, NABIL F
• Application Number:
  US08/447,636
• Time in Patent Office: 294 Days
• Field of Search: 526/206, 526/209
• US Class Current: 526/209
• CPC Class Codes: C08F 14/18 Monomers containing fluorine
• CPC Class Codes: C08F 2/16 Aqueous medium
• CPC Class Codes: C08J 2371/00 Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers
• CPC Class Codes: C08J 3/03 in aqueous media

Abstract

In a process of (co)polymerization in aqueous emulsion of fluorinated olefinic monomers it is added to the reaction medium a microemulsion of fluoropolyoxyalkylenes having hydrogenated end groups and/or hydrogenated repetitive units. A remarkable reduction in the reaction induction period is so obtained, with formation of a product with improved mechanical properties and higher thermal and chemical resistance.

Claims

1. A process of radical (co)polymerization in an aqueous emulsion of one or more fluorinated olefinic monomers, optionally in association with one or more non-fluorinated olefins, wherein said process is operated in the presence of fluoropolyoxyalkylenes having hydrogenated end groups and/or hydrogenated repetitive units added to the reaction medium in the form of an aqueous microemulsion, said fluoropolyoxyalkylenes comprising repetitive units, randomly distributed along the chain, selected from the group consisting of ##STR8## and by hydrogenated end groups selected from the group consisting of --CF₂ H, --CF₂ CF₂ H, --CFH--CF₃, and --CFH--OR_f, where R_f is defined as above, or perfluorinated end groups selected from the group consisting of --CF₃, --C₂ F₅ and --C₃ F₇, at least one of the end groups being hydrogenated.

2. Process according to claim 1, wherein the average molecular weight of the fluoropolyoxyalkylenes is comprised between 300 and 4000.

3. Process according to claim 2, wherein the average molecular weight of the fluoropolyoxyalkylenes is comprised between 400 and 1500.

4. Process according to claims 1, 2 or 3, wherein the fluoropolyoxyalkylenes are selected from the following classes:

##STR9## where;

T₁ and T₂, equal or different from each other, are hydrogenated groups --CF₂ H, --CFH--CF₃, or perfluorinated groups --CF₃, --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

X is --F or --CF₃ ;

a, b are numbers such that the molecular weight is comprised in the range indicated above, a/b is comprised between 5 and 15;

(b) T₃ --O(CF₂ CF₂ O)_c (CF₂ O)_d --T₄

where;

T₃ and T₄, equal or different from each other, are hydrogenated groups --CF₂ H or --CF₂ --CF₂ H, or perfluorinated groups --CF₃, --C₂ F₅, at least one of the end groups being hydrogenated;

c, d are numbers such that the molecular weight is comprised in the range indicated above, c/d is comprised between 0.3 and 5;

##STR10## where;

T₅ and T₆, equal or different from each other, are hydrogenated groups --CF₂ H, --CF₂ CF₂ H, or --CFH--CF₃, or perfluorinated groups --CF₃, --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

X is --F or --CF₃ ;

e, f, g are numbers such that the molecular weight is comprised in the range indicated above, e/(f+g) is comprised between 1 and 10, f/g is comprised between 1 and 10;

##STR11## where;

T₇ and T₈ are hydrogenated groups --CFH--CF₃, or perfluorinated groups --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

h is a number such that the molecular weight is comprised in the range indicated above;

(e) T₉ --O(CZ₂ CF₂ CF₂ O)_i --T₁₀

where;

Z is F or H;

T₉ and T₁₀, equal or different from each other, are hydrogenated groups --CF₂ H or --CF₂ -- CF₂ H, or perfluorinated groups --CF₃, --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

i is a number such that the molecular weight is comprised in the range indicated above;

##STR12## where;

R_f is --CF₃, --C₂ F₅, or --C₃ F₇ ;

T₁₁ and T₁₂, equal or different from each other, are hydrogenated groups --CF₂ H, --CF₂ CF₂ H, --CFH--OR_f, or perfluorinated groups --CF₃, --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

j, k, l are numbers such that the molecular weight is comprised in the range indicated above, k+l and j+k+l are at least equal to 2, k/(j+l) is comprised between 10^-2 and 10³, l/j is comprised between 10^-2 and 10² ;

##STR13## where;

T₁₃ and T₁₄, equal or different from each other, are hydrogenated groups --CF₂ H, --CFH--CF₃, or perfluorinated groups --CF₃, --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

X is --F or --CF₃ ;

m, n, o, p are numbers such that the molecular weight is comprised in the range indicated above, m/n is comprised between 5 and 40, m/(o+p) is comprised between 2 and 50, o+p is at least 3, o is lower than p;

(h) T₁₅ --O(CF₂ CF₂ O)_q (CF₂ O)_r (CFHO)_s (CF₂ CFHO)_t --T₁₆

where;

T₁₅ and T₁₆, equal or different from each other, are hydrogenated groups --CF₂ H, --CF₂ --CF₂ H, or perfluorinated groups --CF₃, --C₂ F₅, at least one of the end groups being hydrogenated;

q, r, s, t are numbers such that the molecular weight is comprised in the range indicated above, q/r is comprised between 0.5 and 2, (q+r)/(s+t) is comprised between 3 and 40, s+t is at least 3, s is lower than t;

##STR14## where;

T₁₇ and T₁₈, equal or different from each other, are hydrogenated groups --CF₂ H, --CF₂ CF₂ H, --CFH--CF₃, or perfluorinated groups --CF₃, --C₂ F₅, --C₃ F₇, at least one of the end groups being hydrogenated;

X is --F or --CF₃ ;

u, v, w, x, y are numbers such that the molecular weight is comprised in the range indicated above, (u+v)/w is comprised between 5 and 40, (u+v)/(x+y) is comprised between 2 and 50, x+y is at least 3, x is lower than y.