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...
Reexamination Certificate
2000-12-22
2003-05-27
Szekely, Peter (Department: 1714)
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...
C526S204000
Reexamination Certificate
active
06569940
ABSTRACT:
The present invention relates to a polymerizable composition comprising a) at least one ethylenically unsaturated monomer, b) a free radical source and c) a 2,2,6,6-tetraalkylpiperidine having a long chain alkyl group. Further aspects of the present invention are a process for polymerizing ethylenically unsaturated monomers, and the use of a 2,2,6,6-tetraalkylpiperidine derivative having a long chain alkyl group for controlled polymerization.
The compounds of the present invention provide polymeric resin products having low polydispersity. The polymerization process proceeds with enhanced monomer to polymer conversion efficiency. In particular, this invention relates to stable free radical-mediated polymerization processes which provide homopolymers, random copolymers, block copolymers, multiblock copolymers, graft copolymers and the like, at enhanced rates of polymerization and enhanced monomer to polymer conversions.
Polymers or copolymers prepared by conventional free radical polymerization processes inherently have broad molecular weight distributions or polydispersities which are generally higher than the theoretical limit of 1.5-2.0. In industrial processes values higher than four are not uncommon.
Conventional radical polymerization processes pose various significant problems, such as difficulties in predicting or controlling the molecular weight, the polydispersity and the modality of the polymers produced. These prior art polymerization processes produce polymers having broad polydispersities.
Furthermore, free radical polymerization processes in bulk of the prior art are difficult to control because the polymerization reaction is strongly exothermic and an efficient heat removal in the highly viscous polymer is mostly impossible. The exothermic nature of the prior art free radical polymerization processes often severely restricts the concentration of reactants or the reactor size upon scale-up.
Due to the above mentioned uncontrollable polymerization reactions, gel formation in conventional free radical polymerization processes are also possible and cause broad molecular weight distributions and/or difficulties during filtering, drying and manipulating the product resin.
U.S. Pat. No. 4,581,429 to Solomon et al., issued Apr. 8, 1986, discloses a free radical polymerization process which controls the growth of polymer chains to produce short chain or oligomeric homopolymers and copolymers, including block and graft copolymers. The process employs an initiator having the formula (in part) R′R″N—O—X, where X is a free radical species capable of polymerizing unsaturated monomers. The reactions typically have low conversion rates. Specifically mentioned radical R′R″N—O. groups are derived from 1,1,3,3-tetraethylisoindoline, 1,1,3,3-tetrapropylisoindoline, 2,2,6,6-tetramethylpiperidine, 2,2,5,5-tetramethyl-pyrrolidine or di-t-butylamine. However, the suggested compounds do not fulfill all requirements.
EP-A-735 052 discloses a general method for preparing thermoplastic polymers of narrow polydispersities by free radical-initiated polymerization, which comprises adding a free radical initiator (free radical source) and a stable free radical agent to the monomer compound.
This method has the disadvantage that uncontrollable recombinations of initiator radicals occur immediately after their formation, thus producing variable ratios between initiator radicals and stable free radicals. Consequently monomer to polymer conversion may become low and/or polydispersity high.
JP 8269117, published 1996 has selected the N-oxyls of bis(2,2,6,6-tetramethyl-4-piperidyl)sebacic acid ester and tetrakis (2,2,6,6-tetramethyl-4-piperidyl)1,2,3,4-butanetetracarboxylate as being particularly useful in controlled polymerization reactions.
Surprisingly it has now been found that 2,2,6,6-tetraalkylpiperidine derivatives having a long chain alkyl or alkylene group in 4 position attached to the piperidine ring are excellent regulators in such systems.
Monomer to polymer conversion is higher as known from prior art polymerizations and polydispersity of the polymers produced is surprisingly low, whereas reaction times are short even at relatively low temperatures, making the polymerization process particularly suitable for industrial applications.
The polymerization processes and resin products of the present invention can be used for a wide range of purposes, for example for pipes, profiles, sheets, cable insulations, sports equipment, garden furniture, films, structural parts, parts of vehicles and machines, and containers of any type, for example bottles, foamed materials, such as insulation panels or packaging material. The polymerization processes are useful for the preparation of block copolymers which are useful as compatibilizing agents or impact modifiers for polymer blends, or dispersing agents for coating systems or for the preparation of narrow molecular weight resins or oligomers for use in coating technologies and thermoplastic films or as toner resins and liquid immersion development ink resins or ink additives used for electrophotographic imaging processes.
The polymers obtainable according to this invention can be brought into the desired shape in known manner. Such processes are, for example grinding, calendering, extruding, injection moulding, blow moulding, sintering and spinning.
The resulting (co)polymers are of high purity, therefore not requiring any further purification.
One object of the present invention is to provide a polymerizable composition, comprising
a) at least one ethylenically unsaturated monomer or oligomer,
b) a radical source capable of starting polymerization of the ethylenically unsaturated monomer or oligomer and
c) at least one compound of formula (I)
n is 1 or 2
R
3
, R
4
, R
9
, R
10
are each independently of one another C
1
-C
18
alkyl, C
2
-C
18
alkenyl or C
2
-C
18
alkinyl; or
R
3
and R
4
and/or R
9
and R
10
form together with the linking carbon atom a C
3
-C
12
cycloalkyl radical;
R
5
, R
6
, R
7
, R
8
are each independently of one another hydrogen, C
1
-C
18
alkyl, C
2
-C
18
alkenyl or C
2
-C
18
alkinyl;
X is —O—, —O—C(O)—, —NR
2
— or —NR
2
—C(O)—;
R
2
is hydrogen, C
1
-C
18
alkyl or phenyl;
if n is 1,
R
1
is C
8
-C
36
alkyl, C
8
-C
36
alkenyl or C
8
-C
36
alkinyl
if n is 2
R
1
is C
10
-C
36
alkylen, C
10
-C
36
alkenylen or C
10
-C
36
alkinylen.
The alkyl radicals may be linear or branched. Examples of alkyl containing 1 to 18 carbon atoms are methyl, ethyl, propyl, isopropyl, butyl, 2-butyl, isobutyl, t-butyl, pentyl, 2-pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, t-octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl and octadecyl.
Examples for alkyl containing up to 36 carbon atoms are eicosyl, docosyl, pentacosyl, hexacosyl, heptacosyl or octacosyl.
The alkenyl radicals may be linear or branched. Examples of C
8
-C
36
alkenyl are octenyl, undecenyl, octadecenyl, eicosenyl, pentacosenyl or octacosenyl.
Examples of C
8
-C
36
alkinyl are 5-undecinyl, 6-octadecinyl, eicosinyl, pentacosinyl or octacosinyl. The alkinyl radicals may be linear or branched.
Typical alkylen groups are decylen, eicosylen, pentacosylen
Preferably R
3
, R
4
, R
9
, R
10
are methyl groups and R
5
, R
6
, R
7
, R
8
are hydrogen.
Preferably X is —O— or —O—C(O)—, more preferably X is —O—C(O)—.
Preferably n is 1 and R
1
is C
8
-C
25
alkyl, more preferably C
11
-C
25
alkyl and most preferably C
15
-C
25
alkyl.
A particularly preferred group of compounds are those of formula
Another preferred group of compounds is, wherein n is 2 and R
1
is C
12
-C
24
alkylen.
R
2
is preferably hydrogen or C
1
-C
4
alkyl.
When the compounds of formula (I) are prepared from commercial grade starting materials the substituent R
1
may often be a mixture of alkyl or alkylene chains of different lengths, centered around a main component.
Preferably the ethylenically unsaturated monomer or oligomer is selected from the group consisting of styrene, substituted styrene, conjugated dienes, acrolein, acrylonitril, vinyl acetate, (alkyl)acrylic acidanh
Clauss Margot
Fuso Francesco
Roth Michael
Wunderlich Wiebke
Ciba Specialty Chemicals Corporation
Stevenson Tyler A.
LandOfFree
Use of 2,2,6,6 tetraalkylpiperidine-N-oxyl radicals having... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Use of 2,2,6,6 tetraalkylpiperidine-N-oxyl radicals having..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Use of 2,2,6,6 tetraalkylpiperidine-N-oxyl radicals having... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3069628