DE1939758C3 - Polyamide-based hot melt adhesive - Google Patents

Description

A. 10-40 mol% aliphatic, open chain and / or cyclic dicarboxylic acids with 4-12 ίο Carbon atoms and aliphatic open-chain and / or cyclic diamines with 2-15 Carbon atoms, with at least half of the diamines having at least three carbon atoms the main chain or the ring contains bonded alkyl groups

B. 10-40 mol% ε-aminocaproic acid

C 25-80 mol% ω-aminocarboxylic acids with

7-12 carbon atoms and possibly
D. small amounts of aromatic dicarboxylic acids or diamines.

2. Use of copolyamides according to claim 1, characterized in that as open-chain diamines with at least three bonded to carbon atoms of the main chain Alkyl groups 2,4,4-trimethylhexamethylenediamine and / or 2,2,4-trimethylhexamethylenediamine, as corresponding cyclic diamine 1-amino-3-aminomethylOAS-trimethylcyclohexane (! sophorondiamine) is used

3. Use of copolyamides according to Claims 1 and 2, characterized in that one the open-chain and cyclic diamines with three carbon atoms of the main chain or des Ring-bonded alkyl groups in a molar ratio of 80:20 to 20:80.

but also the hot water resistance.

Finally, those copolyamides became known as hot melt adhesives, which are polymeric as acid components Contain fatty acids (Skeist, Handbock of Adhesives 1962, ρ 425-433). These copolyamides too In addition to their poor resistance to chemical cleaning, they do not show sufficient resistance to hot water, d. H. they are not sufficiently resistant to hot washing solutions.

Copolyamides based on long-chain amino acids, e.g. aminoundecanoic acid or laurolactam Although hot melt adhesives are suitable for heat sealing textiles, they are not sufficient Wash resistance, d. H. Hot water resistance.

The object of the invention is therefore the disadvantages of To overcome the state of the art and to provide hot-melt adhesives which are both well-watered and resistant as well as being resistant to dry cleaning.

Of course, the melting temperatures should be below 160 ° C.

The problem is solved if copolyamides based on dicarboxylic acids, Diamines and ^ aminocarboxylic acids used from

A. 10-40 mol% aliphatic, open-chain and / or cyclic dicarboxylic acids with 4 to 12 carbon atoms and aliphatic, open-chain and / or cyclic diamonds with 2-15 carbon atoms, where at least half of the diamines have at least three carbon atoms in the main chain or ring contains bonded alkyl groups,

B. 10-40 mole percent 1-4 aminocaproic acid

C. 25-80 mol% of aminocarboxylic acids with 7-12 carbon atoms and possibly

D. small amounts of aromatic dicarboxylic acids or diamines.

40

From US-PS 22 52 555 it is known that copolyamides of at least one diamine with at least one Hydrogen atom on the nitrogen atoms, at least one hydrogen atom on the nitrogen atoms, at least one dicarboxylic acid and at least one monoaminocarboxylic acid also used as a hot melt adhesive can be. Example 1 of this patent describes a binary copolyamide from e-amino-caproic acid and the salt of 2,5-dimethylhexamethyl-5η lenediamine and «/ x'-dimethyladipic acid. This copolyamide Although it has a low melting point; however, this feature is applicable to the processing of textiles alone not sufficient. This copolyamide has a low melting point; this feature is however, it is not sufficient for processing textiles alone. This copolyamide is also not resistant to cleaning, as it is soluble in halogenated hydrocarbons. After all, this copolyamide isn't either Resistant to hot water and also missing a long chain ms term lactam. Caprolactam alone in connection with polyamide-forming components from dicarboxylic acids and diamines are not sufficiently resistant to hot water. The low melting point is a necessary one, though however, this is not a sufficient feature, since in addition ιό the conditions of resistance to hot water and resistance to cleaning must be met. Branched out Although diamines depress the melting point, the following open-chain and cyclic, branched or unbranched aliphatic dicarboxylic acids with 4 to 12 carbon atoms can be used in the hot melt adhesive according to the invention contain for example: succinic acid, adipic acid, 2,2,4-trimethyiadipic acid, azelaic acid, Dodecanedioic acid.Cyclohexane-M-dicarboxylic acid.

The following suitable diamines may be mentioned, for example: Up to 50 mol% of the diamine content is open-chain or cyclic aliphatic unbranched diamines having 2 to 12 carbon atoms, e.g. B. hexamethylenediamine, Dodecamethylenediamine and up to 50 to 100 mol% of the branched diamines, such as 2,4,4- and 2,2,4-trimethylhexamethylenediamine, 1-amino-S-aminomethyl-S.S.S-trimethylcyclohexane.

Ω-Aminocarboxylic acids are also understood to mean their lactams. For example: ω-aminocaproic acid (caprolactam), ω-aminoundecanoic acid, ω-aminolauric acid (laurolactam).

By adding small amounts of aromatic dicarboxylic acids or diamines, the melting temperature can be increased if necessary.

The mean molecular weights of the polyamides used as hot melt adhesives according to the invention are between 2000 and 40,000. The most suitable polyamides for textile bonding have average molecular weights between 6,000 and 25,000.

The copolyamides used can very easily by known methods, for. B. by melt condensation, getting produced. The molecular weights are in a known manner by using a diamine or

Dicarboxylic acid excess or monofunctional by adding Amines or carboxylic acids adjusted during the condensation

The indication of the mol percent refers to the CON Η groups, ie the sum of U, 5 mol of dicarboxylic acid and 0.5 mol of diamine is treated as 1 mol,
treated

The melting temperatures were determined with a hot stage microscope at the temperatures indicated the samples begin to stick to the base.

Adipic acid example 1 1-Amino-S-aminomethyl-S ^^ - trime A copolyamide from cyclohexane 1.06MoI Dodecamethylene diamine 0.60 moles 2,4,4-methylhexamethylene diamine Caproiactam 0.20 mol ω-aminoundecanoic acid 0.20 moles 2.00 Mon! 4.00 moles

is prepared by melt condensation at 200-230 ° C The average molecular weight is 17 000. The melting temperature is 14O ⁰ C, the max. water absorption 8%. The copolymer is dissolved in ethanol and sprayed onto a cellulose fiber fleece. After brief pressing at 130.degree. C., a solid fleece is obtained which retains its strength when washed with 3 ″ washing liquor at 8.degree

Mo! Λ rJInincSiiro Mole Azelaic acid Example el 2 Mole l-amino-S-aminomethyl-S.S.S-trimethyl- A copolyamide from cyclohexane 0.70 Mole Caprolactam 0.30 Mole ω-aminoundecanoic acid 1.08 1.00 5.00

is produced by melt condensation at 200-230 ° C. The mean molecular weight is 14,000. The melting temperature is 150 ° C, the maximum water absorption 12%. This became polyamide Manufactured staple fibers and these in the manufacture of a nonwoven made of nylon 6,6 in an amount by weight of 5% added. The fleece was consolidated by pressing at 120 ° C. When washing in washing water at 100 ° C no strength loss was observed.

Claims (1)

Patent claims: 1. Use of copolyamides based on of dicarboxylic acids, diamines and aminocarboxylic acids as a hot-melt adhesive, characterized in that copolyamides are used as the hot-water-resistant hot-water adhesive