Inherently light- and heat-stabilized polyamides with...

Details Inherently light- and heat-stabilized polyamides with... Inherently light- and heat-stabilized polyamides with...

2000-09-14

2004-11-02

Szekely, Peter (Department: 1714)

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

Synthetic resins

From carboxylic acid or derivative thereof

C528S323000, C528S336000, C524S099000, C524S100000, C524S102000, C524S103000

Reexamination Certificate

active

06812323

ABSTRACT:

The present invention relates to a process for preparing polyamides, which comprises polymerizing starting monomers or starting oligomers in the presence of at least one compound of the formula (I)
where
R is a functional group R
8
which bears 1-4 identical or different amide-forming groups R
7
,
R
1
is H, C
1
-C
20
-alkyl, cycloalkyl, benzyl or OR
6
, where R
6
is H, C
1
-C
20
-alkyl, cycloalkyl or benzyl,
R
2
, R
3
, R
4
and R
5
are independently C
1
-C
10
-alkyl,
n is a natural number greater than 1, and
the piperidine derivatives attached to R are identical or different with regard to the substituents, meaning R
1
, R
2
, R
3
, R
4
and R
5
.
It further relates to polyamides obtainable by this process, to the use of such polyamides for preparing filaments, fibers, films, sheetlike structures and moldings, and to filaments, fibers, films, sheetlike structures and moldings comprising such a polyamide.
The preparation of polyamides, including nylon-6 and nylon-6,6, by addition or condensation polymerization from appropriate starting monomers or starting oligomers is common knowledge (Adolf Echte, Handbuch der technischen Polymerchemie, VCH Weinheim, 1993, p. 553).
The application properties of such polyamides, such as heat stability, light stability, dyeability, resistance to the washing out of color (color wetfastness), are unsatisfactory for many applications.
For instance, coloration problems can arise as a result of chemical changes (oxidative/thermal damage) to the polymer during carpet yarn or textile fabric heat setting. Both continuous filaments and staple fibers can be affected.
It is known to add stabilizers to the polyamide to improve these properties. Such an addition can take place before, during or after the polymerization, for example during the processing.
If the stabilizers are mixed into the polyamide and not attached to the polymer chain, they can migrate, evaporate or wash out of the polymer, so that the effectiveness of the stabilization decreases in an undesirable manner and the surroundings (air, dyebath, cleaning baths) may become contaminated. For instance, DE-A-39 01 717 describes improving the dyeability of polyamides by adding small amounts of at least one amino or imino compound having a cycloalkyl, aryl or hetaryl moiety in the molecule.
The addition of 2,2,6,6-tetramethylpiperidine derivatives with an amide-forming group in position 4 and with or without substitution in position 1 during the polymerization is described for example in WO 95/28443, DE-A-44 13 177, WO 97/05189 and Wo 97/13800. The use of these stabilizers leads to a reduction in the rate of polymerization and hence to higher manufacturing costs for the polyamides due to a reduced space-time yield. In addition, the wetfastness of such polyamides is unsatisfactory.
It is an object of the present invention to provide a process for preparing polyamides, polyamides obtainable by this process, the use of such polyamides for preparing filaments, fibers, films, sheetlike structures and moldings, and also filaments, fibers, films, sheetlike structures and moldings comprising such a polyamide without the disadvantages mentioned.
We have found that this object is achieved by the process for preparing polyamides defined at the beginning, polyamides obtainable by this process, the use of such polyamides for preparing filaments, fibers, films, sheetlike structures and moldings, and also filaments, fibers, films, sheetlike structures and moldings comprising such a polyamide.
Polyamides are herein to be understood as being homopolymers, copolymers, blends and grafts of synthetic long-chain polyamides having recurring amide groups in the polymer main chain as an essential constituent. Examples of such polyamides are nylon-6 (polycaprolactam), nylon-6,6 (polyhexamethyleneadipamide), nylon-4,6 (polytetramethyleneadipamide), nylon-6,10 (polyhexamethylenesebacamide), nylon-7 (polyenantholactam), nylon-11 (polyundecanolactam), nylon-12 (polydodecanolactam). As well as polyamides known by the generic name of nylon, polyamides further include the so-called aramids (aromatic polyamides), such as poly-meta-phenylene-isophthalamide (NOMEX® fiber, U.S. Pat. No. 3,287,324) or poly-para-phenylene-terephthalamide (KEVLAR® fiber, U.S. Pat. No. 3,671,542).
Polyamides can in principle be prepared by two methods.
In a polymerization from dicarboxylic acids and diamines and also in a polymerization from amino acids, the amino and carboxyl end groups of the starting monomers or starting oligomers react with one another to form an amide group and water. The water can subsequently be removed from the polymer. In a polymerization from carboxamides, the amino and amide end groups of the starting monomers or starting oligomers react with one another to form an amide group and ammonia. The ammonia can subsequently be removed from the polymer. This form of polymerization is customarily known as a condensation polymerization or polycondensation.
A polymerization from lactams as starting monomers or starting oligomers is customarily known as an addition polymerization.
Suitable starting monomers or starting oligomers for preparing polyamides are for example:
monomers or oligomers of C
2
to C
20
, preferably C
3
to C
18
, amino acids, such as 6-aminocaproic acid, 11-aminoundecanoic acid, and also their dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of C
2
to C
20
amino acid amides, such as 6-aminocaproamide, 11-aminoundecanoamide, and also their dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of a C
2
to C
20
, preferably C
2
to C
12
, alkyldiamine, such as tetramethylenediamine or preferably hexamethylenediamine,
with a C
2
to C
20
, preferably C
2
to C
14
, aliphatic dicarboxylic acid, such as sebacic acid, decanedicarboxylic acid or adipic acid,
and also dimers, trimers, tetramers, pentamers or hexamers thereof,
monomers or oligomers of a C
2
to C
20
, preferably C
2
to C
12
, alkyldiamine, such as tetramethylenediamine or preferably hexamethylenediamine,
with a C
8
to C
20
, preferably C
8
to C
12
, aromatic dicarboxylic acid or its derivatives, for example chlorides, such as 2,6-naphthalenedicarboxylic acid, preferably isophthalic acid or terephthalic acid,
and also its dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of a C
2
to C
20
, preferably C
2
to C
12
, alkyldiamine, such as tetramethylenediamine or preferably hexamethylenediamine,
with a C
9
to C
20
, preferably C
9
to C
18
, arylaliphatic dicarboxylic acid or its derivatives, for example chlorides, such as o-, m- or p-phenylenediacetic acid,
and also its dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of a C
6
to C
20
, preferably C
6
to C
10
, aromatic diamine, such as m- or p-phenylenediamine,
with a C
2
to C
20
, preferably C
2
to C
14
, aliphatic dicarboxylic acid, such as sebacic acid, decanedicarboxylic acid or adipic acid,
and also its dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of a C
6
to C
20
, preferably C
6
to C
10
, aromatic diamine, such as m- or p-phenylenediamine,
with a C
8
to C
20
, preferably C
8
to C
12
, aromatic dicarboxylic acid or its derivatives, for example chlorides, such as 2,6-naphthalenedicarboxylic acid, preferably isophthalic acid or terephthalic acid,
and also its dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of a C
6
to C
20
, preferably C
6
to C
10
, aromatic diamine, such as m- or p-phenylenediamine,
with a C
9
to C
20
, preferably C
9
to C
18
, arylaliphatic dicarboxylic acid or its derivatives, for example chlorides, such as o-, m- or p-phenylenediacetic acid,
and also its dimers, trimers, tetramers, pentamers or hexamers,
monomers or oligomers of a C
7
to C
20
, preferably C
8
to C
10
, arylaliphatic diamine, such as m- or p-xylylenediamine,
with a C
2
to C
20
, preferably C
2
to C
14
, aliphatic dicarboxylic acid, such as sebacic acid, decanedicarboxylic acid or adipic acid,
and also its dimers, trimers, tetramers, pentamers or hexa

Affiliated with

Also associated with

Rating

Inherently light- and heat-stabilized polyamides with... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Inherently light- and heat-stabilized polyamides with..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Inherently light- and heat-stabilized polyamides with... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3356942