DE1131003B - Process for the production of crosslinked homogeneous elastomers containing urethane groups - Google Patents

Description

INTERNAT.KL. C 08 g

GERMAN

PATENT OFFICE

F33172IVd / 39b

REGISTRATION DAY:

NOTICE THE REGISTRATION AND ISSUE OF EDITORIAL:

FEBRUARY 9, 1961

7th June 1962

There are known processes for the production of crosslinked homogeneous elastomers, linear ones being used Reacts hydroxyl-containing polyesters, polyisocyanates and chain extenders with one another. The chain lengthening agents used are 5 low molecular weight compounds with at least 2 water atoms included, such as B. glycols, diamines, amino alcohols and water, use. Depending on Reaction sequence of the components and their proportions can be the crosslinked elastomers in Casting process or also via storable raw rubber-like intermediate stages according to those in the rubber industry usual "vulcanization process" received.

It is also known to use polyester from e.g. B. to use adipic acid or higher dicarboxylic acids and hexanediol. However, polyesters obtained using such starting components show one increased tendency to crystallization, resulting in hardening and poor cold resistance of the Makes elastomers noticeable. In order to be able to produce more hydrolysis-resistant elastomers based on polyester, However, it is desirable to use polyesters with longer carbon chains in the molecule, e.g. B. hexanediol polyester, to use.

It has therefore already been proposed to use a polyester urethane instead of a simple hexanediol polyester as the starting material, which is obtained by reacting a polyester of glycols and dicarboxylic acids each with at least 5 carbon atoms and a molecular weight of 900 to 1200 with 0.4 to 0.7 mol of a diisocyanate has been obtained. This proposed method is particularly suitable for the production of elastomers with high hardness, which can be obtained by processing in the liquid phase by the so-called casting process. The proposed method is less suitable for the production of hydrolysis-resistant plastics with low hardness and high elasticity, especially when such products are produced via storable intermediate stages. The crystallization tendency of the polyester urethanes, which manifests itself in the melting point from about 40 to 6O ⁰ C, sometimes leads to a hardening of very storable intermediate and thereby complicates the processing of the storage-stable thermoplastic products to the crosslinked elastomers.

The invention is based on the knowledge that hydrolysis-resistant crosslinked homogeneous Elastomers based on linear polycondensates containing hydroxyl and ester groups with polyglycol esters, Polyisocyanates and chain extension processes for their manufacture

of networked homogeneous,

Elastomers containing urethane groups

Applicant:

Paint factories Bayer Aktiengesellschaft, Leverkusen-Bayerwerk

Dr. Arthur Reischl, Dr. Erwin Müller, Leverkusen, and Dr. Wilhelm Kallert, Cologne-Stammheim, have been named as inventors

can be obtained with shaping agents if the condensation products are used as polycondensates from dicarboxylic acids with at least 6 carbon atoms and from addition products of 0.5 to 1.5 mol of a 1,2-alkylene oxide to glycols with at least 6 carbon atoms used.

Such polycondensates, which can have a molecular weight of 1000 to 3000, are at Room temperature partially liquid or with a syrupy consistency. This has the consequence that their reaction products with diisocyanates and chain extenders both in the casting process, as described in German Patent 831 772, as in particular even with the use of proportions that lead to storable thermoplastic Carry products which are "vulcanized" according to the working methods customary in the rubber industry, show no tendency to crystallize. These storable products can get through without any difficulties Mixing in more diisocyanate can be converted into the crosslinked state. The networked products are characterized by very good cold resistance and very high elasticity. Your resistance to hydrolysis is excellent. The inventive method is therefore both for the production of hydrolysis-resistant, highly elastic plastics with high hardness and lower freezing temperature than in particular for the production of soft, highly elastic, hydrolysis-resistant plastics via non-hardening storable intermediate stages suitable.

It is known for the production of polyurethane elastomers containing hydroxyl and ester groups

20 »608/370

3 4

To use polycondensates with polyglycol residues, silicon compounds or carbodiimides, to increase the hydrowelche further by converting a polyether with polybase resistance of the elastomer, see carboxylic acids and subsequent conversion. .
with at least difunctional hydroxyl or amino example 1
connections have been obtained. Compared to these 5,000 parts by weight of a polycondensate made from mono-materials, the present process proethoxylated hexanediol (1,6) and adipic acid (OH products have an improved hydrolysis resistance, a number 56, acid number 1) are at 130 ° C / 12 Torr less tensile strength and structure and an elongation that remains diluted and with stirring with 252 parts by weight of Digere, since on the one hand it contains more numerous phenylmethane-4,4'-diisocyanate and 15 minutes later residues with longer carbon chain links with 50 parts by weight of butanediol (1,4 ) at 100 ° C and on the other hand the ratio of ester to set. After 10 minutes, the adduct is poured into a polythene containing more pre-ether groups on the ester side than in the heated mold and held for 24 hours at 100 ° C.

condensates. It is also used for the production of poly- After any storage time at room temperature ethane elastomers from poly mixed esters from 15 to 1000 parts by weight of adduct 5 weight, which is the acid component of the remainder of the stearic acid, 80 parts by weight of dark 2,4-To isomers of sebacic acid, which contain so-called isosebazin luylene diisocyanate and 3 parts by weight of lead ethylphenyl acid. Elastomers from Isosebazinsäurepoly- dithiocarbamate at 20 ⁰ C rolled (mixing time 10 Mies diesters are indeed low temperature resistant and hydrophobic. The pre-grooves) and at 130 ° C and 200 kg / cm ² pressure 60 Miliegenden process products over but leaves ao grooves pressed with shaping,
their tensile strength and tear strength too low
see left. Their solvent resistance is tensile strength DIN 53504, kg / cm ² .. 309 157

" ¹¹ J ^ '^ j ··" λ λ r,, elongation at break,% 605 820

The inventively to use "polyester" stretch! Minute after tearing, ° / ₀ 11 49

are m known by condensation from 25 ring structure kg / abs 22 18

Dicarboxylic acids with at least 6 carbon atoms, Shore hardness Ά DIN 53505 75 69

ζ. B. adipic acid, methyl adipic acid azelaic acid, E ₁ ^ Mt DIN 53512, % .. '.'. '.'. '.'. '. 50 45
Sebacic acid and 1,2-alkylene oxide addition product

th of glycols with at least 6 carbon atoms g 14 flge aged at 70 ° C and 95% humidity,
manufactured. Of 1,2-alkylene oxides, there are ethylene oxide 30

or called 1,2-propylene oxide. Of glycols.
1,6-hexanediol, methylhexanediol- (1,6) and octodecane example 2
diol mentioned as an example. The addition products contain 1000 parts by weight of the polycondensate from containing 0.5 to 1.5 moles of residues of the 1,2-alkylene oxides game 1, after dehydration, 50 parts by weight per mole of glycol. The amount of 1,2-alkylene oxide depends on dimeric 2,4-toluene diisocyanate below 95 ° C. up to the desired syrupy consistency of the polycondensate for complete dissolution, then 180 parts by weight. A preferred polycondensate corresponds 4,4'-diphenylmethane diisocyanate at 90 ⁰ C is stirred, the residues of adipic acid as an acid component holding Then it is 33.5 parts by weight of butanediol (1,4) in addition to the residues of the addition product of 1 mole at the same temperature with stirring. If necessary, ethylene oxide in 1 mol of 1,6-hexanediol as alcohol is kept below the reaction temperature by cooling. 95 ° C. The clear melt is in molds 2V for ₂ hours

The reaction of the polycondensate with Diiso- at 85 to 95 ⁰ C baked out and the storable intermediate

Cyanate and chain lengthening agent can be demolded cold, like fume product.

Already mentioned, both in the casting process and over 1000 parts by weight of storable intermediate storage Intermediate stages take place. 45 ducts with 200 parts by weight of carbon black and

As chain extenders, for example, 3 parts by weight of lead-ethylphenyl-

Glycols such as 1,4-butanediol, p-phenylene-ß-dihydroxydithiocarbamate and 5 parts by weight of stearic acid

ethyl ether or diamines, such as 3,3i'-dichloro-4,4'-di- room temperature mixed on a roller,

aminodiphenylmethane, or also called water. It The networking of these storable thermoformed

however, other known chain-extendable synthetic resins with built-in uretdione groups can also be used

funds are used. expediently takes place in molds at 130 ° C and

As diisocyanates for processing in liquid ^{pressure of 200 kg / cm 2} for 15 minutes. To complete

Phase over the casting process are particularly 1,4-Naph- the reaction is the demolded material

diisocyanate, 4,4'-diphenylmethane diisocyanate so-20 hours at 100 ⁰ C reheated,

as well as toluene diisocyanate worth mentioning. 55 from

To produce the storable intermediate, the _{tensile strength DIN 53} 504, kg / cm ² .. 286 134

m takes place in a manner known per se, the same elongation at break ⁰ I 505 710

Diisocyanates and chain extenders- elongation 1 minute after breaking, «/; 6 19

sets are For the networking of storable _Rin ^ ur kg / abs 16 15

Intermediate products are particularly em dimeric diiso- 60 _sho ° _e . _{Hardness A} % _{m 53505} ....... _{68 55}

cyanate suitable that also after the process de

_shoe . _{Hardness A} % _{m 535}

cyanate suitable that even after the method of V) ^ H ₇ HHt DTKT v? S19 ° / 50 39

^{German patent specification} 1 014 740 while maintaining the ^{tlastlzItat by 3} ^ ¹ A / 0 ^3υ ^

Uretdione groups in the storable intermediate product?) Unaged. ,, ·, · "

can be built in. For cross-linking, ^{b) U days aged at 70 C and 95} "> humidity,

other of the known diisocyanates use 65,,

Find. Example 3

It is of course possible with the help of 1000 parts by weight of the polycondensate from others known additives, such as organic game 1 are dehydrated and at 115 to 120 ° C with

180 parts by weight of 1,5-naphthylene diisocyanate reacted with stirring. After the diisocyanate has dissolved, 20 parts by weight of 1,4-butanediol are immediately stirred in and the still liquid reaction mixture is poured into molds heated ^{to HO 0 C.} At 100 to 110 ° C one bakes freely for 24 hours.

Example 4

Following the procedure of Example 2, 100 parts by weight of the polycondensate from Example 1 are obtained with 33.5 parts by weight of butanediol (1.4) and with 100 parts by weight dimeric 2,4-tolylene diisocyanate and 140 parts by weight of 4,4'-diphenylmethane diisocyanate implemented a storable raw rubber-like skin.

The processing of the raw fur into the elastomer takes place as in Example 2.

Tensile strength DIN 53504, kg / cm ² .. 236

Elongation at break,% 387

Elongation 1 minute after breaking,% 3

Ring structure, kg / abs 13

Shore hardness A DIN 53505 70

Elasticity DIN 53512,% 46

a) Unaged.

b) Aged for 14 days at 70 ^° C. and 95% humidity.

186
334
7th
17th
58
37

20th

Example 5

A storable raw rubber-like skin according to Example 4 is produced. Incorporation of the Fillers and the crosslinking with shaping takes place as in Example 2, only 400 instead of 200 parts by weight Active carbon black is used.

away

Tensile strength DIN 53504, kg / cm ² .. 250 214

Elongation at break,% 272 425

Elongation 1 minute after breaking,% 3 6

Ring structure, kg / abs 25 34

Shore hardness A DIN 53505 79 69

Elasticity DIN 53512,% 39 32

a) Unaged

b) Aged for 14 days at 70 ^° C. and 95% humidity.

Claims (2)

PATENT CLAIMS: 1. A process for the production of crosslinked, homogeneous elastomers containing urethane groups based on linear polycondensates containing hydroxyl and ester groups with polyglycol residues, polyisocyanates and chain extenders with shaping, characterized in that the condensation products of dicarboxylic acids with at least 6 carbon atoms and addition products of 0 as polycondensates , 5 to 1.5 moles of a 1,2-alkylene oxide on glycols with at least 6 carbon atoms can be used. 2. The method according to claim 1, characterized in that a polyester of adipic acid and the addition product of 1 mole of ethylene oxide to 1 mole of 1,6-hexanediol is used. Documents considered: German Auslegeschrift No. 1 056 367; U.S. Patent No. 2,902,462. © 209 608/370 5.62