Perfluoropolyether compounds as additives in formulations

Details Perfluoropolyether compounds as additives in formulations Perfluoropolyether compounds as additives in formulations

2001-02-28

2003-08-19

Wu, David W. (Department: 1713)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

At least one aryl ring which is part of a fused or bridged...

C524S013000, C427S385500, C427S393500, C117S106000, C424S200100

Reexamination Certificate

active

06608138

ABSTRACT:

The present invention relates to the use of additives for the protective treatment of wood materials to confer improved oil- and hydro-repellence properties.
Specifically, the invention relates to the addition of additives to the formulations usually utilized for the wood treatment, such as for example impregnating, antivegetative, insecticidal formulations, etc. Said additives are effectively used at very low surface concentrations, avoiding to modify the surface aspect of the treated wood material.
Compounds able to give wood hydro-repellence properties are known in the prior art. U.S. Pat. No. 5,141,983 which describes polyurethane-acrylic copolymers dispersed in water can for example be mentioned. The drawback of these products consists in that they are not able to confer suitable oil-repellence properties.
Other compounds, for example functionalized amino-organo hydrogenated siliconates are described in U.S. Pat. No. 5,178,668. Also for these products, there is the drawback that they are unable to confer suitable oil-repellence properties.
In U.S. Pat. No. 5,855,817 compounds having more than one hydroxyl function in combination with quaternary ammonium salts to confer hydro-repellence to wood, are described. Also in this case the oil-repellence properties are not high.
There are also aqueous formulations based on siliconates, polyurethanes and silicates, described in U.S. Pat. No. 5,356,716. Also in this case no mention is made to possible conferred oil-repellence properties.
Hydrocarbon solvent-based formulations comprising mixtures of fluoropolymers, hydrogenated silanes and silicones are described in U.S. Pat. No. 5,593,483. Also in this case no mention is made to possible conferred oil-repellence properties.
In U.S. Pat. No. 5,691,000 specific perfluoropolyether phosphor monoester compounds able to give hydro- and oil-repellence to wood are described. The solvents used for the dissolution of these compounds are CFC-113 or alcohol/water mixtures. In this patent also other perfluoropolyether compounds having different functionalities are exemplified. The Examples show that these latter derivatives have lower hydro- and oil-repellence properties in comparison with the perfluoropolyether phosphor monoesters. In particular, the hydro-repellence values of phosphor monoesters when applied on wood are unsatisfactory. In fact, the Applicant has noticed that the oil- and hydro-repellence test is not sufficiently discriminating to identify the real protection degree given to wood. For this reason, these products have found a poor commercial application for the protective wood treatment. In this patent no mention is made to the use as additives of said products in the formulations used for wood.
The technical problem that the present invention intends to solve is that to find additives showing the following property combination:
improved hydro-repellence properties;
improved oil-repellence properties;
absence of any change of the wood natural aspect;
substantial maintenance of the properties conferred by impregnating, antivegetative, insecticidal, etc., formulations also after additive addition;
good compatibility of the additive with impregnating, anti-vegetative, insecticidal, etc. formulations so as to have substantially uniform oil- and hydro-repellence properties on the surface of the treated wood;
improvement of the wetting capacities of the above mentioned formulations for wood;
improved friction coefficient, i.e. decrease of the friction coefficient values of the wood surface which implies a wear limitation.
The need was therefore felt to have available additives for formulations used in the wood treatment, able to give the combination of the above mentioned properties.
An object of the invention are therefore mono- and bifunctional perfluoropolyether compounds and their use as additives in formulations for the wood treatment, excluding the formulations based on paraffin waxes dissolved in hydrocarbon solvents, said perfluoropolyether compounds having the following structures:
R
f
—CFY—L—W  (C)
W—L—YFC—O—R
f
—CFY—L—W  (D)
wherein:
L is an organic group selected from —CH
2
—(OCH
2
CH
2
)
n
—,
—CO—NR′—, with R′═H or C
1
-C
4
alkyl group;
n=0-8, preferably 1-3;
Y═F, CF
3
;
W is selected from C
1
-C
50
alkyl groups, preferably C
8
-C
25
, optionally containing one or more ether O, C
6
-C
50
aryl groups, C
7
-C
50
alkyl-aryl or aryl-alkyl groups;
R
f
has a number average molecular weight in the range 350-8,000, preferably 500-3,000 and it comprises repeating units having at least one of the following structures, statistically placed along the chain:
(CFXO), (CF
2
CF
2
O), (CF
2
CF
2
CF
2
O), (CF
2
CF
2
CF
2
CF
2
O),
(CR
4
R
5
CF
2
CF
2
O), (CF(CF
3
)CF
2
O), (CF
2
CF(CF
3
)O),
wherein
X═F, CF
3
;
R
4
and R
5
, equal to or different from each other, are selected from H, Cl, or perfluoroalkyl from 1 to 4 carbon atoms.
In particular Rf can have one of the following structures:
1) —(CF
2
O)
a′
—(CF
2
CF
2
O)
b′
—
with a′/b′ in the range 0.5-2, extremes included, a′ and b′ being integers such as to give the above mentioned molecular weight;
2) —(C
3
F
6
O)
r
—(C
2
F
4
O)
b
—(CFXO)
t
—
with r/b=0.5-2.0; (r+b)/t is in the range 10-30,
b, r and t being integers such as to give the above mentioned molecular weight, X has the above mentioned meaning;
3) —(C
3
F
6
O)
r′
—(CFXO)
t′
—
t′ can be 0;
when t′ is different from 0 then r′/t′=10-30,
r′ and t′ being integers such as to give the above mentioned molecular weight; X has the above indicated meaning;
4) —(OCF
2
CF(CF
3
))
z
—OCF
2
(R′f)
y
—CF
2
O—(CF(CF
3
)CF
2
O)
z
—
wherein z is an integer such that the molecular weight is the above mentioned one;
y is an integer between 0 and 1 and R′f is a fluoroalkylene group having for example 1-4 carbon atoms;
5) —(OCF
2
CF
2
CR
4
R
5
)
q
—OCF
2
(R′f)
y
—CF
2
O—(CR
4
R
5
CF
2
O)
s
—wherein:
q and s are integers such that the molecular weight is the above mentioned one;
R
4
, R
5
, R′f, y have the above mentioned meaning;
6) —(C
3
F
6
O)
r′″
(CFXO)
t′″
—OCF
2
(R′f)
y
—CF
2
O(CF(CF
3
)CF
2
O)
r′″
(CFXO)
t′″
—
wherein r′″/t′″=10-30,
r′″ and t′″ being integers such as to give the above mentioned molecular weight;
R′f and y having the above mentioned meaning.
In the above indicated formulas:
—(C
3
F
6
O)— can represent units of formula —(CF(CF
3
)CF
2
O)— and/or —(CF
2
—CF(CF
3
)O)—
In the structure (C) wherein Rf is monofunctional, the other end group is of the T—O— type, wherein T is a (per) fluoroalkyl group selected from: —CF
3
, —C
2
F
5
, —C
3
F
7
, —CF
2
Cl, —C
2
F
4
Cl, —C
3
F
6
Cl; optionally one or two F atoms, preferably one, can be replaced by H.
The mentioned fluoropolyethers are obtainable by the well known processes in the prior art, see for example the following patents herein incorporated by reference: U.S. Pat. Nos. 3,665,041, 2,242,218, 3,715,378, and EP 239,123. The functionalized fluoropolyethers are for example obtained according to EP 148482, U.S. Pat. No. 3,810,874.
The compounds of structure (C) are obtained by reacting a monofunctional perfluoropolyether ester derivative with an alkylamine. The alkylamine, generally under waxy form, is melted at a temperature in the range 40°-60° C. The perfluoropolyether ester derivative is dropped in the amine in an equimolar amount under stirring and maintaining the reactor at the desired temperature. At the end of the addition the alcohol which has formed from the condensation reaction is evaporated.
The compounds of structure (D) are obtained by reacting a bifunctional perfluoropolyether ester derivative with an alkylamine. The alkylamine, generally under waxy form, is melted at a temperature in the range 40°-60° C. The bifunctional perfluoropolyether ester derivative is dropped in the amine in molar amount 0.5 with respect to the amine u

Affiliated with

Also associated with

Rating

Perfluoropolyether compounds as additives in formulations does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Perfluoropolyether compounds as additives in formulations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Perfluoropolyether compounds as additives in formulations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3084055