DE1961226C2 - Crystalline polyester molding compound containing glass fibers - Google Patents

Description

or

(where Y is the meaning of
- (CH ₂ ), - - (CHA-CO- (CH ₂ ) ,,

- (CH ^ —O— (CH ₂ ) .-

-0- (CH ₂ LO- -

- (CH ₂ ) .- S- (CH ₂ ,) .-

-S- (CH ₂ J _n -S-
or

-SO ₂ -

40

has [n is an integer from 0 to 4 and m is an integer from 1 to 5]) or their esters in the presence of 5 to 100 parts by weight of polystyrene, per 100 parts by weight of the polyester, and 10 to 40% glass fibers, based on the weight the mass, has been produced.

2. Mass according to claim 1, characterized in that the mass additionally contains a filler contains.

3. Composition according to claim 1, characterized in that the polystyrene is made of monomeric Styrene was made during the manufacture of the polyester.

60

The invention relates to a crystalline Polyeslerformmassc containing glass fibers.

Although crystalline polyesters, such as polyethylene terephthalate, are widely used in manufacture are used by fibers and films, it has not been possible to date in a satisfactory manner, polyester for to use other shaped articles besides films and fibers.

Molded articles made of crystalline polyester, such as polyalkylene terephthalate, are exposed to high humidity, at a higher temperature or in boiling water, due to a lower deformation temperature, low impact resistance and low water resistance useless. Because of this, the application was the above polyester as a raw material for molded articles without economical Importance.

About heat resistance and impact resistance To improve, attempts were made to add glass fibers to the molding compound. By adding fiberglass the thermal stability is largely improved and the impact resistance extremely greatly improved. The addition of glass fibers also increases the physical properties, such as tensile strength and Tensile modulus, improved.

However, reinforcement of the molded article by adding glass fiber leads at the same time to a decreasing formability with an increasing amount of glass fiber. For example, if you give the glass fibers in an amount of 20 to 40 percent by weight, which corresponds to the optimal amount in view of on the physical properties of the article, there are considerably more severe molding conditions necessary. The addition of glass fibers also has the disadvantage of poor water resistance do not fix the manufactured item.

Many attempts have been made to solve the above problems, and it has been found that a glass fiber-containing molding compound from a polymer mixture, which by reacting of glycol with a dicarboxylic acid or its ester in the presence of polystyrene, does not have the above disadvantages and also has new properties which the conventional Moldings made from glass fiber reinforced polystyrenes or moldings made from glass fiber reinforced polyesters are not present.

To change the properties of a particular polymer, one often blends another Polymer. In some cases, this gives a polymer mixture whose properties match the aiithmetic mean of the properties of each Components corresponds; in other cases, however, a mixture with poorer properties is obtained, at which properties of one or both mixed polymers are lost .Ie after In the special case, however, not only do the properties of the two components appear when mixed, but also new properties that do not result from the properties of the individual mixed components derive. Furthermore, the miscibility of these different polymers largely depends on the compatibility of the polymers; this dependency rests in some cases on essential ones Properties of the polymers and in other cases on the mixing ratio and the applied Mixing process. Even if the compatibility of the two polymers is so poor. that you don't get mixed ability to achieve mechanical mixing of the two polymers, can nevertheless be a < Miscibility to a certain extent due to the polymerisation of one polymer in the presence achieve the other. Even in the case of good compatibility between the two polymers, one can hurry Polymer mixture with completely different properties than with simple mechanical mixing

of the polymers obtained by building up one polymer in the presence of the other polymer executes.

When you consider the mechanical blending of two polymers with blending during polymerization compares, no differences are observed in the chemical composition of the two mixtures, but there are considerable optical differences in the masses. It follows that the polymer mixture produced by the last-mentioned process from a homogeneously mixed Polymers is made.

If the properties of the molding compound are improved or new properties achieved by adding another polymer and the polymer mixture thus obtained If you want to further reinforce with glass fibers, you have to make the selection, the mixing process, the precisely select the optimum amount, etc., of the various polymers to be added: it is also necessary to the composition, shape, amount, type of addition and other conditions of the glass fiber addition accordingly to choose.

It is known that moldings made of glass fiber reinforced polystyrene have improved flexural strength, Has tensile strength and compressive strength compared to molded bodies made of non-reinforced polystyrene: on the other hand, the low impact resistance and heat resistance, wekhe die They represent disadvantages of polystyrene, not improve them. It is also known (see, for example, the Japanese Offenlegungsschrift 22069/67) that the properties of polyphenylene oxide by adding polystyrene for flowability and can improve mechanical properties

A method in which polystyrene, which is a completely non-crystalline polymer. to a highly crystalline polycondensate. such as polyethylene terephthalate. added and the mixture thus produced is reinforced with glass fibers but not known.

In the context of the invention, the mechanism of glass fiber reinforcement of a polymer mixture, by adding polystyrene to a highly crystalline polyester such as polyethylene terephthalate. was established. It was surprisingly found that a glass fiber containing Molding compound made of crystalline polyester mixed with polystyrene, which can be prepared by adding a corresponding amount of polystyrene was obtained in the polycondensation of the polyester, excellent Has properties that neither glass fiber reinforced polyester nor glass fiber reinforced polyester Polystyrene are present.

The subject of the invention are molding compounds consisting of glass fibers and a polystyrene compound crystalline polyester, which is obtained by polycondensing a glycol of the general formula

HO- (CH ₂ ) ,, - OH

in which ρ is an integer from 2 to 10, and a dicarboxylic acid of the general formula

HOOCR ₁ XR ₂ COOh

in which R ₁ and R, _{mean - (CH 2} I _n -Im means O or an integer from I to 4) and X is a divalent aromatic group of the general formula

or

(where Y is the meaning of

"5 - (CH ₂ )" - - (CH ₂ J _n -CO- (CH ₂ ).

- (CH ₂ J _n -O - (CH ₂ ), -

-0- (CH ₂ LO-

~ (CH ₂ ) "- S— (CH ₂ ) ,, -

S (CH ₂ J _n S -

C -

or

- SO,

owns [/! denotes an integer from 0 to 4 and m an integer from 1 to 5]) or their esters in the presence of 5 to 100 parts by weight of polystyrene per 100 parts by weight of the polyester, and 10 to 40% glass fibers, based on the weight of the mass, has been made.

The styrene polymer used according to the invention can be polystyrene itself or a copolystyrene with a content of over 80 percent by weight styrene.

Examples of comonomers are acrylonitrile and methacrylate. Butadiene and dimethyl styrene.

The polystyrene has a molecular weight of 10,000 to 1,000,000 and is used in an amount of 5 to 100 parts by weight based on 100 parts by weight of the polyester, preferably in an amount from 5 to 70 parts by weight and especially from 30 to 50 parts by weight added.

The amount of glass fibers to be added for reinforcement is expediently between 10 and 40 percent by weight, based on the weight of the molding compound. In this case the physical depend Properties, as in the known processes, largely depend on the shape and surface treatment of the added glass fibers. and one must carefully observe these conditions in order to idcalt to achieve physical properties.

Glass fibers with a length of 0.2 mm or more, preferably up to 100 mm, are preferably used. a diameter of 1 to 50 ■> _ to a ratio of length to diameter voi 20 or above, preferably up to 10 000. Additional lent a surface treatment, these fibers of course, is appropriate, wherein the treatment mi of an aminosilane compound. Epoxysilane compound

or a melhacrylic acid-chromium complex of the Werner type, according to the formula

Cl ₂ Cr

CrCl ₂

is particularly effective.

The glass fibers treated in this way can be added to the molding compound in a manner known per se respectively.

The fiber-reinforced mass obtained in this way can also contain fillers. Dyes, an antistatic agent Contains anti-flammable agents and a lubricant.

Carbon and graphite are suitable as fillers. Lime, a compound containing silicon and oxygen, like aluminum silicate. powdered mica, powdered granite, slate powder or Lime; a metal oxide such as magnesium oxide, titanium oxide or antimony trioxide; an alkali salt, such as sodium carbonate, Potassium carbonate, sodium oxalate. Potassium oxalate or potassium benzoate; an alkaline earth salt, like calcium carbonate. Calcium sulfate or calcium oxalate: a metal powder, such as finely powdered copper or antimony powder, as well as glass powder: also Deca-Iin. Naphthalene, benzophenone, diphenylamine or tetrachloroethane.

The polycondensation of glycol with a dicarboxylic acid or its ester is listed under conventional conditions such as, for example in Japanese laid-open publications 4547/51 and 4640'53 are described. Polystyrene can in front the beginning of the condensation reaction of the glycol with the dicarboxylic acid or its ester or during added to the condensation reaction. Polystyrene must be present in the system, before the condensation reaction has ended.

Accordingly, the styrene monomer can be polymerized in the course of producing the polyester.

The effect of the invention will be based on the drawings with a view to changing the physical properties explained, the amount of polystyrene added and the amount the added glass fibers to that of glass fibers, polystyrene and polyethylene terephthalate according to the The following examples were modified in a number of ways. In the drawings means

Fig. 1 shows the dependence of the tensile strength on the amount of glass fiber added, using a polymer mixture obtained by polycondensation of ethylene glycol with dimethyl terephthalate in the presence of polystyrene.

F i g. 2 the dependence of the tensile modulus on the amount of glass fiber added,

F i g. 3 the dependence of the Izod impact strength on the amount of glass fiber added and

Fig. 4 shows the relationship between time and Melt stability in boiling water for a poly mixed with various amounts of polystyrene ethylene terephthalate.

The tensile strength wedge, as can be seen from FIG Exceeds the tensile strength of glass fiber reinforced polyester or non glass fiber reinforced, with poly styrene-mixed polyester by far. The tensile module as shown in FIG. 2 is also in comparison to glass fiber reinforced polyester or non-glass

ίο fiber-reinforced polyester mixed with polystyrene improved since. According to Fig. 3 result that the impact strength wedge of polystyrene mixed polyester without the addition of glass fiber is almost not increased; on the other hand, the impact

ij strength in a mass produced by adding 5 to 70 parts by weight of polystyrene to 100 parts by weight of polyester with increasing amount of added glass fiber.
4 shows the decrease in the viscosity of the polymer mixture in percent as a function of the cell when a polyethylene terephthalate mixed with polystyrene is immersed in boiling water. The viscosity was measured in a solution containing 0.5 percent by weight of the polymers in a mixed solvent of phenol and tetrachloroethane at a weight ratio of phenol to tetrachloroethane = 1: 2. As the amount of polystyrene content increases, the percentage reduction in the

kosity.

The invention will now be explained in more detail with reference to the following examples. Refer to the examples all parts and percentages are based on weight.

Example !

To a mixture of 100 parts of Dimethylterc-

Phthalate and 80 parts of ethylene glycol became 33 parts of polystyrene with a molecular weight of 150,000 admitted. To the mixture was added 0.06 part of calcium acetate was added, and then the ester interchange reaction was carried out at a temperature of 220.degree

carried out until no more methanol distilled off. Then 0.03 part of antimony oxide was added to the reaction mixture was added, and the reaction was continued at 280 ° C. at a pressure of 0.1 mm Hg Run for 3 hours.

A glass sliver treated with aminosilane with 12,000 monofibers and a diameter of 10 μ was with the polymer mixture thus obtained like a coating for an electric wire coated, the glass content being 30 percent by weight

fraud.

This material was made into a molded article at an injection temperature in a syringe molding machine from 260'C. a pressure of over 700 kg cm- and a mold temperature of 110 ° C processed.

For comparison purposes, a molded article of the same composition, which had been prepared by mixing in a mixer in the molding stage, with regard to the physical properties investigated.

The following Table 1 shows the physical properties of the molded articles thus obtained shown.

Table I.

at example comparison example Tensile strength wedge, kg cnr 1500 1300 Elongation at break. ¹ O 5.0 7.0 Tensile modulus, kgcnr IK) (XM) 95 (KX) Impact resistance. 16.0 14.0 kg cm / cm Deformation tempera door 102 89 under action of warmth. (C [18.6 kg cnr]) game 2

example

1 5.0

Impact resistance,
kg cm / cm

Deformation temperature KX)
in the warmth
(C [18.6 kg cm ² ])

Comparison·"
example

11.4

82

To a mixture of 130 parts of bishydroxyethyl tercphthalate. O. (X) 7 parts of germanium dioxide and 0.07 parts of triphenyl phosphite were KX) parts of polystyrene with a molecular weight of 51 (XX) added, and the reaction was carried out at 280 C and a pressure of 0.1 mm Hg in the course of Run for 4 hours. Then (with a methacrylic acid-chromium complex of the Werner type), according to the formula

H ₂ CC-CH.,

c-

Cl ₂

O
CrCl,

Example 3

A mixture uus KX) parts of dimethyl terephthalate. 80 parts of ethylene glycol and 33 parts of monomer! Styrene was heated to 140 ° C. and then 0.05 part of benzoyl peroxide was added, and so it was obtained reaction mixture was reacted for 2 hours. Then there was 0.06 part of calcium acetate and 0.01 part of germanium dioxide was added, and the ester interchange reaction was carried out at 220 C, until no more methanol distilled off. Then the reaction was carried out at 280 ° C under one pressure of 0.04 mm Hg over 4 hours. In the same way as in Example I was made the polymer mixture thus produced, to which 30% aminosilane-treated glass fibers were added had been shaped. For comparison purposes, a molded article of the same composition, the components of which, however, had been mixed in a mixing device, and the physical properties of the two molded articles were compared with each other.

In Table 3 are the physical properties of the molded articles thus obtained are juxtaposed with each other.

treated glass fiber added in the same way as in Example 1, the glass content being 30 percent by weight fraud.

The molding material thus obtained was extruded at an extrusion temperature of 250 ° C., an extrusion ^{pressure of 900 kg cm 2} and a mold temperature of 100 ° C. to obtain a molded article weighing 40 g. For the purpose of comparison, a molded article of the same composition, which was mixed in a mixer during the molding step, was prepared, and the physical properties of the two substances were compared with each other.

In Table 2, the physical properties of the molded articles thus obtained are compared.

Table 3

example Comparison: example Tensile strength, kg, cnr 1600 13CX) Elongation at break. % 7.0 7.0 Tensile modulus, kg / cm ² 120000 95,000 Impact resistance, 17.0 14.0 kg / cm / cm Deformation temperature 108 89 under action of warmth (C [18.6 kg / cm ² ])

Table 2

Tensile strength, kg / cm ²
Elongation at break. %
Tensile modulus, kg cnr

example

1400

5.0

100,000

Comparative example

1210
8.5
85 0 (X)

60

Example 4

The physical properties of the mass according to

Example 1. to which graphite, talc and calcium benzoate in an amount of 0.5% each. based

on the glass fiber reinforced mass, added before was. are compiled in Table 4.

10

[dragonfly 4

RiIkIoIl graphite Cikiuni-
hen / oal Talk 1650 1700 Tensile strenght,
kg cm ² 1550 5.0 5.0 Elongation at break. 5.0 I 20 (M) O 130,000 Zuiz module.
kg; cm ² 115,000 16.5 15.5 Impact resistance,
kg cm cm 16.0 250 255 Deformation tem
temperature below
Impact
of warmth
(C [18.6 kg
cm ² ]) 244

From Table 4 it can be seen that the addition of the filler further improves the physical properties be improved.

Example 5

A molded article was produced by molding in the same manner as in Example 1, wherein however, instead of the 20 parts of dimethyl terephthalate, dimethyl isophthalate was used.

The physical properties of each one obtained here molded article are shown in Table 5 below.

Table 5 Example 6

/ u a mixture of 100 parts of dimethyl ester \ on 1.2-bis-p-carboxyphenoxyethane and 48 parts of ethylene glycol were 50 parts of polystyrene with a Molecular weight of 100,000 was added, and then 0.06 part of calcium acetate was added, and the ester exchange reaction was carried out at 220 ° C. until no more methanol distilled off. then 0.03 parts of antimony oxide were added, and the polycondensation reaction was carried out at 280 C and carried out at a pressure of 0.1 mm Hg over the course of 3 hours.

A glass fiber treated with epoxysilane and having a diameter of 10 _: / and a length of 6 mm was added to the polymer mixture thus obtained until the glass content was 30%. The mass thus obtained was extruded in an extruder with a diameter of 30 mm to give granules for molding purposes. Thereafter, these granules were molded by extrusion molding at an extrusion ^{temperature of 260.degree. C., an extrusion pressure of 700 kg / cm 2} and a mold temperature of 100.degree. The physical properties of the molded article thus obtained are shown in Table 6 below.

For the purpose of comparison, the physical properties of a molded article were made of the same Composition, the components of which, however, are mixed in a mixing device in the molding stage were determined.

, see table 6

Tensile strength, kg cm ²
Elongation at break,%
Tensile modulus, kg cm ²
Impact strength, kg cnrcm
Veriormung temperature below
Exposure to heat
(C [18.6 kg / cm ² ])

example For this 40 Tensile strength, kg cm ² example Comparison;
example Tensile modulus, kg''cm ² 1620 Impact resistance. 1750 1 600 6.5 _4S kg / cm cm 134000 1 1 5 (X) O 117 (XK) Deformation temperature 15.5 13.6 17.2 in the warmth 92 (C [18.6 kg cm ² ]) 104 100 2 sheets of drawings

Claims (1)

Patent claims: 1. fiber mass, consisting of glass fibers and a crystalline polyester mixed with polystyrene, which by polycondensing a glycol of the general formula HO - (CH ₂ ), - OH in soft ρ is an integer from 2 to 10, and a dicarboxylic acid of the general formula HOOCR ₁ XR ₂ COOh in which R ₁ and R _{2 have} the meaning of - (CH ₂ ) .- (n represents O or an integer from 1 to 4) and X represents a divalent aromatic group of the general formula