DE2706082A1 - GLASS SUBSTITUTES BASED ON POLYHEXAMETHYLENE ISOPHTHALAMIDE - Google Patents

Description

Claim

Glass substitutes, consisting of at least 60% by weight Polyhexamethylene isophthalic acid amide.

Le A 17 808 - 15 -

809833/0361

ORIGINAL INSPECTED Bayer Aktiengesellschaft 2706082

Central area of patents, trademarks and licenses

5090 Leverkusen, Bayerwerk Str / AB

Feb 10, 1977

Glass substitutes based on polyhexamethylene isophthalamide

Glass has very good transparency, surface hardness, Rigidity, chemical and solvent resistance as well as heat resistance, but in comparison to others Materials have a low impact strength and elongation at break. Glass is therefore very prone to breakage. Another The disadvantage is that it is difficult to process, since the shaping from the melt is necessary high temperature and high melt viscosity, machining due to its great hardness and brittleness is made more difficult. For many purposes it is also its relatively high specific weight is unfavorable.

Glass substitutes are therefore mainly used where

in addition to at least one advantageous property of the glass, high impact strength, good processability and / or a low specific weight is necessary.

Since the listed properties are partially mutually exclusive, a range of different, more transparent ones is required Active ingredients to have the right glass substitute available for every conceivable application. Economic However, reasons make it necessary to keep this range as small as possible. One is

Le A 17 808

809833/0351

therefore endeavors to find glass substitutes with the broadest possible area of application to use.

Experience has shown that particularly broad areas of application can be covered with materials that are clearly superior to glass in terms of impact strength, processability and weight and also meet certain minimum requirements in the aforementioned properties of transparency, surface hardness, rigidity and strength, chemical and solvent resistance and heat resistance. This is the case with a number of thermoplastic and thermoset plastics. The processability of these materials is consistently good; their specific weight is below 1.5 Mg / m ³ (glass> 2.3 Mg / m 3).

As Table 1 shows, transparent polyamides are particularly suitable as glass substitutes. While with thermosetting resins the low impact strength, with PVC, polystyrene and cellulose ester the low heat resistance, yield stress and surface hardness and, in the case of methyl polymethacrylate, the low impact strength is the area of application to a limited extent, some transparent polyamides show optimal values for the combination of these properties on. Also polycarbonate, which is known as a glass substitute due to its transparency and its good mechanical properties has proven itself well, has not achieved it in terms of yield stress, modulus of elasticity (Zu?) and surface hardness the values found with transparent polyamides. Furthermore, the tendency of polycarbonate to undergo stress cracking narrows its field of application a.

Le A 17 808 - 2 -

809833/0351

Despite this superiority of the transparent polyamides over other glass substitutes, some are mechanical Properties of the glass not achieved. This is particularly true with regard to the surface hardness, which the The basis of its high scratch resistance is.

It was therefore an object of the present invention to provide transparent polyamides which have the above-mentioned disadvantages do not exhibit.

It has now surprisingly been found that polyhexamethylene isophthalic acid amide within the group of transparent polyamides with regard to the combination of properties of impact strength, Yield stress, flexural strength, modulus of elasticity, surface hardness and hydrolysis resistance are top positions occupies. Due to its low melt viscosity, its processing is also similar to that for thermoplastic Plastics usual process facilitated.

Its low water absorption is also remarkable. This must be can be seen as an advantage, since polyamide parts are less resistant to water absorption in terms of strength, rigidity and electrical properties deteriorate and change their dimensions. Copolyamides based show similar properties of polyhexamethylene isophthalamide.

These polyamides are therefore particularly suitable as glass substitutes. They can be used, for example, as a substitute for glass in optics, the lamp and watch industry , especially in the manufacture of transparent molded parts, where hardness, scratch resistance and impact resistance are important , e.g. protective glasses and sunglasses, Fesnel lenses and sight glasses such as lamp _U. nd watch covers. Another area of application is the production of transparent objects that have particular rigidity, strength, weather resistance and impact strength. Le A 17 808 - 3 -

809833/0351

• S ·

(especially in the cold), e.g. glazing of telephone booths, exhibition cabinets, waiting room houses, Sports facilities and vehicles. They can also be used to manufacture parts at which in addition to transparency, hardness and impact strength are good Resistance to hot water, solvents, fuels, oils, greases and chemicals are necessary, e.g. of viewing windows, housing parts and covers in apparatus engineering, the food industry, sanitary and Installation area, of medical devices, household appliances and utensils such as lighter tanks and containers of all kinds such as bottles or glasses. Another preferred field of application is manufacture more transparent parts, in which, in addition to the properties already mentioned, hardness, toughness and strength electrical properties such as insulation, tracking resistance and arc resistance play a role, e.g. switch boxes, bobbins, device housings, insulating bodies and switching chambers.

The invention therefore relates to glass substitutes that consist of at least 60 wt .-% polyhexamethylene isophthalphenylamide.

Instead of isophthalic acid, the dicarboxylic acid residues can also contain up to 10% by weight, preferably up to 5% by weight, of aliphatic dicarboxylic acids with C _fi -C. ₂ * such as adipic acid, dodecanedioic acid, sebacic acid, cyclohexanedicarboxylic acids, or up to 40% by weight (preferably up to 30, particularly preferably up to 20% by weight) of aromatic dicarboxylic acids with Cg-C ₂₀ such as

Le A 17 808 - 4 -

809833/0351

Derive terephthalic acid, naphthalenedicarboxylic acid, benzophenonedicarboxylic acid, diphenylethericarboxylic acid, diphenylmethanedicarboxylic acid. The hexamethylenediamine can be replaced by up to 30% (preferably up to 20%) by other diamines, for example by linear or branched aliphatic diamines with C ₉ -C ₁₆ , such as decamethylenediamine, dodecamethylenediamine or trimethylhexamethylenediamine, and also by cycloaliphatic diamines with Cg- C. g, such as 1,4-diamino-cyclohexane, 4-aminomethylcyclohexylamine, 3-aminomethyl-3-5,5-trimethyl-cyclohexylamine, bis- (4-aminocyclohexyl-) methane or propane, piperazine or bis-aminomethylnorbornane, and by araliphatic diamines with C_-C_q, such as m-xylylenediamine or bis (aminoethyl) benzene.

Furthermore, up to 30% of lactams with at least 7 ring members such as caprolactam, laurolactam or aminocarboxylic acids can be used such as aminoundecanoic acid or aminobenzoic acid are incorporated as comonomers.

In addition to polyhexamethylene isophthalic acid amide, the glass substitutes according to the invention can be used nor auxiliaries and additives such as molecular weight regulators, mold release agents, and contain weather stabilizers, fire retardants or colorants.

The glass substitutes according to the invention can, as already mentioned, for the production of transparent molded parts, such as optical objects, glazing, Covers, housings or housing parts are used.

Le A 17 808 - 5 -

809833/0351

(D

Tabel Comparison of properties of glass substitutes

oo

00

Impact strength, flexural strength, yield stress E-MDdul, heat-resistant, ball pressure or Tensile strength (tensile strength) according to Vicat hardness

2 ^part ο

kJ / m MPa MPa MPa C MPa

until 30

until

up to 3500

180-200

CD O CO OO CO CO

(Phenolic resins, UP resins, melamine resins; epoxy resins)

Cellulose ester

Polystyrene PVC (hard)

Poly (methacrylic acid methyl ester)

partly not broken

not broken

<

<

80

2000

3000

<

50-70 to 3000 8O-100 3000 7O-

125

<

to 120

190

Polycarbonate

Transparent polyamides

not broken

not broken

60

150-155

80-100 2600-3000 125-160

95

120-200

O CO O QO

example 1

In a stirred autoclave, 100 parts of a salt of hexamethylenediamine and isophthalic acid, 0.44 part of benzoic acid and 0.02 part of excess hexamethylenediamine are initially added for two hours under a nitrogen atmosphere
220 ° C, then polycondensed for three hours at 270 ° C. A transparent polyamide is obtained (hereinafter referred to as
Polyamide I) with a relative solution viscosity of 2.6 measured in m-cresol (25 ° C, c = 1 g / 100 ml).

Furthermore, copolyamides are prepared in an analogous manner in which 10 or 20 mol percent of the hexamethylenediamine is carried out 3-aminomethyl-3,5,5-trimethyl-cyclohexylarain have been replaced (hereinafter referred to as polyamide II or III).

The following table summarizes some properties of the transparent polyamides obtained in this way and some of the properties available on the market transparent polyamides together. It shows the superiority of polyhexamethylene isophthalamide in relation to the combination of properties investigated.

Le A 17 808 - 7 -

809833/0351

"ν, O CJ

(D

00

00

OO

Impact strength limit bending E-Mcdul

Tension (bending test)

MPa

Ball indentation hardness Lichttrans-H 30 mission

MPa

Polyamide I polyamide II polyamide III

Handelsübl. Polyamide made from terephthalic acid and trimethylhexamethylenediamine

Adipic acid and hexamethylenediene / bis-4-aminocyclohexylpropane "^ ⁺

Handelsübl. Polyamide from aliphatic, aranatic and cycloaliphatic Basic building blocks

not broken

not broken not broken

not broken

not broken

not broken 155 2800

167 2800

177 3000

125 2900

130 no information

180

170

200

125

155

> 85

> 85

> 85

85-90

not specified

110-120 1700-1900

110

not specified

according to publications from Dynamit Nobel AG

according to publications from BASF

according to the publications of the company Faser Werke AG

cn ο oo

Example 2 '^ D "

To test for resistance to hot water, standard small rods made of polyhexamethylene isophthalamide and two commercially available transparent polyamides are boiled in distilled water with access to air. The weight increase Δ G and the behavior of the test specimens are shown in the table below.

Le A 17 808 - 9 -

809833/0351

OD O CO OD U> CJ

Cooking time Polyhexamethyl earth phthalamide Obvious cloudiness Handelsübl. Polyamide made from adipine and hexarnethylenediamine / bis- Cloudiness Handelsübl. Polyamide from Tere Turbidity; surface
orange-like ge
welled Obvious cloudiness acid 4-amir «> - cyclohexylpropane + Cloudiness, swelling phthalic acid and trimethyl-hexa- Parts loosened, strong ones
Cloudiness Severe cloudiness AG Increasing cloudiness methylenediamine ++ Glue the test specimen!
and go away;
Attempt aborted A G Re-reading the 1.8% Severe cloudiness Δ G 4th
• 2 hours. 1.7% Cloudiness 3.6% Persistent cloudiness ₂
Impact strength «! 0 kJ / m 0.9% 8 hours 3.5% Turbidity largely ver
dwindled. No break
in the impact strength
test. No molecule off
building 4.9% 2.6% 24 hours 4.3% 5.9% 4.2% 5 days 5.1% 6.1% 12 days 5.1%

+ Ultramid KR 1297/2 from BASF ++ Trogamid T from Dynamit Nobel

cn ο OO

Example 3

/ la

Standard small rods made of polyhexamethylene isophthalamide were stored for 6 months at room temperature in various solvents and chemicals and then examined for weight gain, impact strength and visually perceptible changes. The results are shown in the following table; a decrease in impact strength
was not observed in any case. For comparison, the manufacturer's information on the resistance of two commercially available transparent polyamides to the same reagents is included.

Le A 17 808 - 11 -

809833/0351

reagent Polyhexams
amide
Weight
increase % ethylene isophthalic Commercial
pinic acid ι
diamine / bi
propane +
Weight
increase 4 L. polyamide from adi-
and hexamethylene
s-4-amino-cyclohexyl- Commercial:
phthalic acid]
methylating.
Weight
increase% .. polyamide made of tere- '
re and trimethyl-hexa-
Lamin ++ acetone 1.7 no change 11 resistant conditionally resistant Ammonia 25% 4.2 no change 12th resistant conditionally resistant petrol 0.2 no change 1 resistant resistant benzene 0.3 no change 3 resistant resistant Butyl acetate 0.6 no change 10 resistant resistant Καα-icpüiirre S% 5.5 slight cloudiness 13th Cloudiness not specified """■■ J ■""■" ■ * " ~ * ^w
Pr> riTwlin Ii * 5.0 slight cloudiness not specified G· conditionally resistant Glycerin 0.2 no change 3 resistant resistant Glycol 1.1 no change 34 resistant not specified Potash 10% 4.5 no change 10 conditionally resistant f resistant Caustic soda 10% 3.9 no change 9 conditionally resistant I. resistant Trichlorethylene 0.5 no change inconsistent resistant

+ ültramid KR 1297/2 from BASF ++ Trogandd T from Dynamit Nobel

NJ - <!

cn ο 00

Example 4 - AU-

To assess the processability of thermoplastics, a thin rod is injected with the sprue at one end and which is generally rolled up in a spiral ("flow spiral"). The rod length filled by the material is a measure of its flowability. At 3 mm rod thickness, 260 ° C cylinder and 80 ° C mold temperature for high molecular weight polyhexamethylene isophthalamide (y , in m-cresol = 2.64 at 25 ° C, c = 1 g / 100 ml) a flow length of 26 cm, for a low molecular weight setting (n . = 2.3) a flow length of 31 cm, measured for a commercially available transparent polyamide made from terephthalic acid and trimethylhexamethylenediamine (Trogamid ™ from Dynamit Nobel) a flow length of 11 cm.

Example 5

Polyhexamethylene isophthalamide is made on a screw injection molding machine with a screw diameter of 36 mm at a cylinder temperature of 270 C and a mold temperature of 80 ° C to form round plates 80 mm in diameter and 2 mm thick. You get Plates of 11.6 g weight, good surface finish and good transparency. The light transmittance according to ASTM D 1003 is 86.5%, the haze 2.2%. Leave the plates are processed into protective glasses, which are characterized by high impact resistance, high resistance to solvent vapors, characterized by good surface hardness and scratch resistance.

Example 6

Polyhexamethylene isophthalamide is injected into lighter tanks on a screw injection molding machine at a cylinder temperature of 270 ° C and a mold temperature of 80 ° C. The tank bottoms are attached in dark white, the tanks are crystal clear and suitable

Le A 17 808 - 13 -

809833/0351

. 4b

due to their chemical resistance and their mechanical strength as a fuel container for gas and Benz in lighters.

Example 7

A commercially available single-screw extruder with a screw diameter of 60 mm and an L: D ratio of 25 is equipped with a slot die. The cylinder temperatures from the funnel to the mold are 240/250/260 ° C. A 5 mm thick plate is extruded over a calender is drawn off with a roller temperature of 100 - 120 ° C. Due to their high transparency, the panels obtained can be Use scratch resistance and toughness for the production of glazing, e.g. on telephone booths and motor vehicles.

Example 8

From 3 mm thick polyhexamethylene isophthalamide plates, produced analogously to Example 7, are made by deep drawing Lamp covers in the shape of a truncated cone with the final diameters 8 and 13 cm and 12 cm in height. One uses a vacuum thermoforming machine with IR heating, the preheating time is 1 minute. The lamp covers obtained are transparent, impact-resistant and scratch-resistant.

Le A 17 808 - 14 -

609833/0351