JPS59207930A - Polyamide elastomer - Google Patents

Abstract

PURPOSE:A polyamid elastomer, consisting of specific polyamide hard segments and polyether ester soft segments, and capable of exhibiting improved oil and chemical resistance and good rubber elasticity and mechanical strength within a wide temperature range covering low - high temperatures. CONSTITUTION:A polyamide elastomer obtained by copolymerizing (A) polyhexamethylene sebacamide or polyhexamethylene dodecanamide as main hard segments with (B) a polyester ether obtained from a poly(alkylene oxide)glycol having >=2.3 ratio between the numbers of C and O and 300-3,000 number- average molecular weight and a 4-20C dicarboxylic acid as soft segments in 50-90wt% soft segments, and adjusting the copolymerization ratio within (10- 50)/(90-50) weight ratio range between the components (A) and (B) to exhibit the following physical properties; >=160 deg.C melting point, 45D-80A Shore hardness, 1,000-100kg/cm<2> tensile elasticity and >=70% elastic recovery.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyamide elastomer having a segmented polyether ester amide as its basic skeleton.

Like polyether ester and polyether amide, polyether ester amide is known as a thermoplastic elastomer having excellent impact resistance and rubber elasticity (U.S. Pat. Nos. 4,207,410 and 4,230,838). In fact, only polyamide elastomers based on polydodecanamide/poly(tetramethylene oxide) glycol are commercially available. This polymer has physical properties and moldability comparable to polyester elastomers, and has the advantage of being able to be made into a more flexible copolymer composition, but has the disadvantage of not having sufficient high-temperature characteristics, oil resistance, or chemical resistance. There is. In particular, in the high temperature range of 100°C or higher, the elastic modulus and strength decrease significantly, and the reality is that it is virtually unusable at temperatures of 120°C or higher.

It is also known that when polycaproamide (nylon 6) is used for the 71-do segment, a polyether ester amide with a relatively high melting point can be obtained, but this polymer has a large amount of nylon 6 components and is difficult to use in the hard polymer region. Although it exhibits excellent high-temperature properties, a flexible polymer region with a high poly(alkylene oxide) glycol component causes a rapid drop in melting point, making it impossible to design a polymer that has both flexibility and high-temperature properties. This copolymer system is also difficult to manufacture industrially, as lactam is distilled off from the system during polycondensation. Furthermore, when polyhexamethylene adipamide (nylon 66) is used as a hard segment, its affinity with polyether components such as poly(tetramethylene oxide) glycol is extremely low, and it is often Since a coarse phase-separated system is formed over a wide range, it is impossible to obtain a thermoplastic elastomer exhibiting excellent rubber properties.

In view of the shortcomings of conventional polyamide elastomers, the present inventors have maintained flexibility, impact resistance, and excellent moldability at low temperatures, while maintaining excellent mechanical strength even in the high temperature range of 100°C or higher. The present invention has been arrived at through extensive research aimed at producing a thermoplastic elastomer exhibiting rubber-like properties.

That is, the present invention uses polyhexamethylene diamine (N-6
10') or polyhexamethylene thicanamide (
N-612) as the main hard segment, carbon number/
The ratio of oxygen numbers is 23 or more and the number average molecular weight is 300 to 3
．． The present invention provides a polyamide elastomer containing 50 to 90 weight percent of a polyether ester made from a poly(alkylene oxide) glycol of 0.000 and a dicarboxylic acid having 4 to 2.0 carbon atoms as a soft segment, and exhibiting the following physical properties.

Melting point: 160°C or higher Shore hardness: 45D to 80. A Tensile modulus 1.000 to 100 kq/d Elastic recovery rate 70% or more Boria 2 of polyether ester amide in the present invention
The dohard segment is polyhexamethyleneadipamide (nylon 61) formed from hexamethylene diamine and sebacic acid or dodecanedioic acid and their derivatives.
0) or a polyamide unit containing polyhexamethylene thicanamide (nylon 612) as a main component, as a polyamide unit, a large amount of polyamide, diamine, octamethylene diamine, decamethylene, etc. Diamines such as amines, untecamethylenediamine, his(p-aminonechlorohexyl)methane, xylyleneleamine, adipic acid, azelaic acid, isophthalic acid, terephthalic acid, cyclohexane-1,4-carboxylic acids It may contain dicarboxylic acid units such as.

The polyether component constituting the polyether ester soft segment of the polyether ester amide of the present invention is poly(alkylenoxide) having a carbon/oxygen number ratio of 2.3 or more and a number average molecular weight of 300 to 3,000. ) using glycol. Poly(alkylene oxide) glycols with a carbon/oxygen ratio of 2.3 or higher include:
Poly(1,2- and 1,3-propylene oxide) glycol, poly(tetramethylene oxide) glycol, poly(hexamethylene oxide) glycol, block or lantam copolymers of ethylene oxide and propylene oxide, ethylene oxide and 1-Rofurano Ichinor" or lantum copolymers, among others, poly( Tetramethylene oxide) glycol is preferably used. Poly (alkylene oxide)
The number average molecular weight of glycol can be used in the range of 300 to 3.000, but a molecular weight range that does not cause coarse phase separation during polymerization and has excellent high-temperature to low-temperature properties and mechanical properties is selected, and this optimum molecular weight range is (alkylene oxide)
Depends on the type of glycol. For example, in the case of poly (propylene oxide) glycol, it is 300 to 2,000
Particularly preferably 600 to 1.200, and in the case of poly(tetramethylene oxide) glycol, 500 to 2.
500! Preferably, those having a molecular weight in the range of 500 to 1.500 are used for r.

The dicarboxylic acid having 4 to 20 carbon atoms, which is another component constituting the ether ester noft segment + one unit of the polyether ester amide of the present invention, is the same as the dicarboxylic acid used for the polyamide hard segment component; That is, it is preferable to use sebacic acid or dodecanedioic acid, but they do not necessarily have to be the same. Aromatic dicarboxylic acids such as 2,6-dicarboxylic acid, naphthalene-2, fudicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, diphenoxyethanocarboxylic acid, striium 5-sulfoisophthalate, 1,4- Cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, dicyclohexaneru 4.4
Mention may be made of alicyclic dicarboxylic acids such as '-dicarboxylic acids. Among these, terephthalic acid is particularly preferred since it provides good polymerization reactivity, color tone, and good results. The use of dicarboxylic acids other than terephthalic acid, sebacic acid, and dodecanedioic acid may impair high-temperature properties, so their use is limited depending on the copolymer composition and purpose of use.

That is, the most preferable copolymer composition according to the present invention is nylon 6/10 or nylon 6/12, especially nylon 6/12 with hard semeno I-, and a number average molecular weight of 5.
00-2500 poly(tetramethylene oxide) glycol and sepadino acid (hard segment is nylon 6e)
10), dotecanleic acid (hard segment) is a polyether ester amide block copolymer containing a polyether ester from nylon 6/12) or terephthalic acid, particularly terephthalic acid, as a soft segment. .

The present invention is a copolyether ester amide consisting of these polyamide hard segment 1- and polyether ester soft segment 1-, and the copolymerization ratio of polyamide units and polyether ester medium is (10 to 5 (1/(9)
0 to 50) (weight ratio) and must be copolymerized so as to have the following physical properties. In particular, polyether ester soft segments 1 to 55 have a melting point of 160°C or higher based on ASTM
D3418 Shore hardness 45D~80A
ASTM D2240 tensile modulus 1,000~
100kq/d ASTM D-638 elastic recovery rate
70% or more JIS K6301 (5
It is preferable that the copolymer is copolymerized in a range of 0% elongation to 80% by weight, and this copolymer is not only flexible and has excellent rubber elasticity at room temperature, but also has excellent properties as an elastomer in a wide temperature range from low to high temperatures. It exhibits excellent physical properties and formability.

If the polyether ester component exceeds 90%, the length of the amide hard segment of the resulting polyether ester amide becomes too short, resulting in a polymer with poor physical properties, which is not preferred.

Among the physical properties of the polymer, the most important item that defines the high-temperature properties, which is the main objective of the present invention, is the melting point, which is generally 160' although it also depends on the degree of crystallinity, crystal form, crystal perfection, etc. The polymer should be designed to exhibit a melting point of 180° C. or higher, preferably 180° C. or higher.

Although the method for polymerizing polyetheresteramide having such a structure is not particularly limited, it is possible to synthesize a polyetheresteramide that meets the purpose of the present invention by the following method.

ia) He-j-+j methylammonium sebacate (nylon 610m) or hexamethylene diammonium dodecanoate-1 (nylon 612 salt') itb
) poly (alkylene oxide) glycol and (C
) Poly(alkylene oxide) glycol and dicarboxylic acid in substantially equimolar amounts were added to the reaction system at the copolymerization ratio described above, homogenized by heating and stirring at 150 to 280°C, and then Melt polymerization is carried out at 220-300°C under vacuum. Starting material is poly(alkylene oxide)
Since glycol is sometimes liquid, but generally solid, it can be made into a homogeneous liquid mixture by heating and stirring at 150 to 280°C, particularly preferably 180 to 260°C, for about 10 to 60 minutes under normal pressure. Here, the state of "homogeneous" does not necessarily mean that they are mixed on a molecular order, but rather refers to a state in which there is no layer separation or the like as a whole, even if the appearance is cloudy. The reaction system is then brought into a vacuum system, preferably at elevated temperature to polymerization conditions of 220-300°C under high vacuum for about 20-90 minutes. High vacuum means a range of about 15 or less Hg, preferably 5 or less Hg, more preferably 1zzHg or less, which is equivalent to the degree of vacuum used in ordinary melt polymerization of polyester. By this method, the block polyether ester amide of the present invention can be industrially advantageously synthesized as a polymer with a high degree of polymerization by promoting coloring, but it is also possible to bring the amide-forming unit into the above reaction system without first converting it into a salt form. can. In this case, it is necessary to control the reaction conditions of the dissolution homogenization process so that the amine is not distilled out of the system. Alternatively, the amide-forming unit component and the dicarboxylic acid component may be prepared in advance into a dicarboxylic acid-terminated boria ε-doped prepolymer, and this may be reacted with poly(alkylene oxide) glycol. It is necessary that the acid component and the lucicarboxylic acid component constituting the a-position of the polyether ester be the same or be terephthalic acid. Otherwise, the polyamide hard segments would be randomly copolymerized, making it impossible to produce a flexible elastomer with excellent high-temperature properties, which is the object of the present invention.

In the polymerization reaction of the polyether ester amide of the present invention, a titanium-based catalyst such as a tetraalkyl titanate such as tetrabutyl titanate, a titanium metal salt of oxalate such as potassium titanium oxalate, dibutyltin oxide, dibutyltin laurate, monobutyltin oxide, etc. Preferably used are tin-based catalysts such as zirconium tetrabutoxide, tonozirconium tetraalkoxide-based catalysts such as zirconium isopropoxide, hafnium tetraalkoxide-based catalysts such as hafnium tetraethoxide, and lead-based catalysts such as lead acetate. It will be done. These compounds act as polymerization catalysts to promote the reaction, and are advantageous in easily producing the colorless, highly polymerized polymer of the present invention, which has excellent physical properties. Further, polyfunctional compounds such as trinosinic acid, glycerin, penquerythritol, etc. can be included as long as they do not cause gelation.

The degree of polymerization of the polyether ester El' of the present invention varies depending on the use, purpose, and molding method, but the relative viscosity of the solution (ηr) measured at 0.5% concentration in chlorophenol at 25°C Do you have 15 or more? and preferably 1.
It should be 7 or more.

The polyether ester adblock conjugate of the present invention can contain a heat-resistant and light-resistant stabilizer such as an oxidation pressure-protecting agent, a thermal decomposition inhibitor, and an ultraviolet absorber during polymerization or after polymerization and before molding. . As a heat stabilizer, for example, 4
,41~bis(2,6-di-tert-butylphenol), 1
,3,5-trimethyl-2,4,6-1-lis(3,5
-di-tert-butyl-4-hydroxypencyl)benzene,
Tetrakis [methylene-3(3,5-;F3butyl-4
-hydroxyphenyl)propionate]methane, N
, various hindered phenols such as N'-hexamethylene bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamic acid amide);

Aromatic amines such as N'-his(β-naphthyl)-p-phenyleramino and 4,4'-bis(4-α,α-dimethylpencyl)diphenylamine, dilaurylthiodipropione-1, etc. Examples include sulfur compounds and phosphorus compounds, alkaline earth metal oxides, nickel salts of Schiff bases, cupric iodide and/or potassium iodide, and the like. In addition, as light stabilizers, substituted benzophenones, benzotriazoles, His(2,2,6,
6-titranoter-4-piperidine) sebacate and 4-
Mention may be made of piperidine compounds such as benzoyloxy-2,2,6,6-titramethylpiperidine.

The polyether ester amide block copolymer of the present invention also contains hydrolysis resistance improvers, coloring agents (pigments, dyes), antistatic agents, conductive agents, flame retardants, reinforcing materials, fillers, lubricants, nucleating agents, release agents, etc. A molding agent, plasticizer, adhesion aid, adhesive, etc. can be optionally contained.

As described above, since the polyamide elastomer of the present invention has a specific copolymer composition, it exhibits excellent oil and chemical resistance, as well as excellent rubber elasticity and mechanical strength in a wide temperature range from low to high temperatures.

The present invention will be explained below with reference to Examples. In the examples, unless otherwise specified, parts mean parts by weight.

Example 1 Hexamethylenediamine-dodecanedioic acid salt (nylon 6
12 salt), 53.9 parts of poly(tetramethylene oxide) glycol having a number average molecular weight of 650, and 19.1 parts of dodecanedioic acid were added to N,N'-hexamethylene-bis(3°5-di-t). -butyl-4-hydroquinohydrocinnamic acid amide) (antioxidant, trade name: Ilkanox '1098) and 0.05 part of tetrabutyl titanate catalyst in a reaction vessel equipped with a helical ribbon stirring blade. The mixture was heated and stirred at 230° C. for 1 hour under a N2 stream to obtain a homogeneous solution, and then brought to polymerization conditions of 270° C. and Q, 5 ygHg or less according to a temperature increase and pressure reduction program. When the polymerization reaction was carried out under these conditions for 4 hours and 10 minutes, a viscous, colorless and transparent molten polymer was obtained. When this polymer was discharged as a strand into water, a flexible, non-tacky strand was obtained. The obtained polyether ester amide (11 in or-1-chlorophenol, 25
The relative viscosity (ηr) measured at ℃ and 0.5 part concentration is 1.8
2, and the crystal melting point (Tm) by DSC was 193°C. In addition, in the following examples and comparative examples, ηr, T
m is based on this method.

The mechanical properties measured from the press-molded product are as shown in Table 1, and it was flexible and had rubber elasticity, and showed excellent mechanical strength even at high temperatures.

Comparative Example 1 Using 38.2 parts of aminododecanoic acid, 50.1 parts of poly(tetramethylene oxide) glycol with a number average molecular weight of 650, and 17.7 parts of dodecanedioic acid as starting materials, polyether was produced under the same polymerization conditions as in Example 1. Esteramide (1
I prepared strawberries. ηr of this polyether ester amide
is 1.80.

T]η was 139°C. As shown in Table 1, the mechanical properties were as good as those of Example 1 from low temperatures to room temperature, but the elastic modulus and strength decreased significantly at high temperatures, and at 120°C, it almost flowed.

Comparative Example 2 Hexamethylenediamine-adipate (nylon 66
When 34.8 parts of poly(tetramethylene oxide) glycol having a number average molecular weight of 650 and 13.5 parts of adipic acid were polymerized in the same manner as in Example 1, phase separation was produced. However, the polymer turned brown and cloudy. Furthermore, the degree of polymerization was low, and only a polymer with low elastic recovery rate and strength could be obtained.

23℃ Shore D hardness ASlM D-2240 Shore D383
8 Tensile modulus ASTM D-b38 kq/l
J 540 460 10% modulus
#40
34 breaking stress / 3
00 320 Elongation at break // ″
% 850 900 Elastic recovery rate JISK63
01 r 80, 78 (50% elongation) -30℃ Tensile modulus ASTM D-638kg/cd 2
900 3300.

10% Moji-+, 5th tt
// 240 27
080℃ Tensile modulus ASTM D-638kq/cd 3
30 130 breaking stress //
16θ 55 elongation at break t
% 7o0 700120℃ Tensile modulus ASTM D-638 phantom 7ca 92
ill [<possible Q1@) Breaking stress
81〃Example 2-4 Nylon 6.12 salt, polyester with number average molecular weight ff1650
(tetramethylene oxide) glycol (PTMG-6
Three types of polyether ester amides (1), (Ill+, and (IV)) were prepared using polymerization conditions similar to those in Example 1 using 5(N) and terephthalic acid as starting materials. The physical properties of these polymers are shown in Table 2. show.

Table 2 Example 2 Example 3 Example 4 Raw materials (parts by weight) (…) (I
II) α) Nylon 612 salt 27.
9 33.5'41.3PTMG-65062,55
8,352,5 terephthalic acid 16.0
14.9 134 Polymer properties ηr 1,87 1.84
1.78 partsm CCI 1
92 199 202 Shore D hardness 23℃
31 38 43 Tensile modulus 23℃
410 520 900 (kg/cd) 8
0℃ 300 350 550120℃
86 120 360 breaking strength 23℃
280 330 410 (kg/cd) 80℃
130 160 250120℃ 9
7 110 160 failure - affirmation 23℃ 1
200 850 750 (to) 80℃
1150 850 850120℃ 7
50 90'0 100Q Elastic recovery rate 23℃
85 82 75 (f) Nylon 6/12 salt 27.9 parts, number average molecular weight 1000
Poly (tetramethylene oxide) glycol 66.
Polyether ester amide tV+ was prepared under the same conditions as in Example 1 except that 4 parts of terephthalic acid
was polymerized. Highly polymerized and odorized to the specified torque in a polymerization time of 3 hours and 55 minutes.

A pale white translucent polymer was obtained. The hard/soft ratio of the polymer was 25/75, and the physical properties were as follows.

ηr 1.90 Tm ■) 198 Mechanical properties 23°C Shore D hardness 30 Tensile modulus (kg/d') 350 Breaking strength (lI) 320 Elongation at break (%) 1050 Elastic recovery rate (%) 88 80°C Tensile Elastic modulus (tg/d) 280 breaking strength (/
/ ) 170 Elongation at break (%) 950 120°C Tensile modulus (kV/Cd) 110 Strength at break (// ) 120 Elongation at break (%) 950 Comparative example 3 Hard/soft ratio in Example 5 is 60/40 When polymerized in this manner, the polymer became milky white and coarse phase separation was formed. The extruded polymer from the polymerization vessel showed a large balancing effect and could not be collected as a waste.

Comparative Example 4 27.9 parts of nylon 612 salt, 71.1 parts of poly(tetramethylene oxide) glycol having a number average molecular weight of 3500
An attempt was made to synthesize a polyether ester amide having the same hard/soft ratio as in Example 5 using 1 part and 4.7 parts of dodecanedioic acid as starting materials, but the polymer exhibited a pearly milky white color and coarse phase separation was formed. This polymer was also difficult to take off as a strand, but it turned into pellets, and when its physical properties were measured as a plain sheet, the breaking strength was 13 at 23°C.
0 kq/d, and the elongation at break was 34091, but 8
At 0°C, it showed almost no strength.

Example 6 27.9 parts of nylon 612 salt and 11.9 parts of terephthalic acid.
1 part was placed in a polymerization container and heated to 230°C to 250°C under a N2 stream.
The reaction mixture was heated and stirred at ℃ for 2 hours, and the number average molecule 11
000 poly (tetramethylene oxide) glycol 66.4 parts, TeI-butyl tita, ? , -1-0,0
5 parts and 0.20 part of Iruka Knox '1098 were added, and the polymerization conditions were then brought to the same conditions as in Example 1, and the predetermined torque was reached after 5 hours and 30 minutes. The physical properties of this polymer are shown in Table 3.

Comparative Example 5 In Example 6, 27.9 parts of nylon 612 salt, 9.9 parts of arnipic acid, and 676 parts of poly(tetramethylene oxide) glycol having a number average molecular weight of 1000 were used as starting materials. Even after 8 hours of polymerization, the predetermined torque was not reached and the color of the polymer remained brown, so it was taken out and subjected to evaluation. As shown in Table 3, this polymer has a low melting point and poor high temperature properties.

Table 3 ηr 1,89 1.77 Tm (C) 200 145 Mechanical properties 23°C Nyore D hardness 30 29 Tensile modulus (J/cd) 330 310 Strength at break (// ) 290 200 Elongation at break (%
') 950 650 Elastic recovery rate (%) 83
7880℃ Tensile modulus (kq/cd) 260
130 breaking strength (〃 )150 72
Elongation at break (%) 950 700 120°C Tensile modulus (J/cd) 105 Unmeasurable (fluid) breaking strength (〃) 95 Example 7 28.2 parts of nylon 610 salt, poly(Te1-La) with a number average molecular weight of 650 methylene oxide) glycol 62.5
Tepolyetheresteramide was polymerized under the same polymerization conditions as in Example 1 except that 16.0 parts of terephthalic acid and 16.0 parts of terephthalic acid were used as starting materials.

The physical properties of the obtained polymer were as follows.

ηr
186 copiesm (C)
208 Mechanical properties 23℃ Shore D hardness 34 Tensile modulus (k
g/cd) 380 Breaking strength (, Il) 24
0 Elongation at break (%) 700 Elastic recovery rate (ll') 76 80℃ Tensile modulus (kg/cd) 280 Strength at break (#) 130 Elongation at break (%) 850 120℃ Tensile modulus (kg/cd) 120 at break Strength (p) 75 Elongation at break (%) 550 Patent applicant Toshi Co., Ltd.

Claims (1)

[Scope of Claims] The main hard segment is polyhexamethylene sebacamide or polyhexamethylene dodecanamide, the carbon number/oxygen number ratio is 2.3 or more, and the number average molecular weight is 3.
A polyamide containing 50 to 90% by weight of a poly(alkylene oquindo) glycol of 00 to 3'000 and a polyether ester from a dicarboxylic acid having 4 to 20 carbon atoms as a rough 1-segment, and exhibiting the following physical properties. Elastomer. Melting point 160℃ or higher Shore hardness
45D~80A Tensile modulus 1,000~100h/d Elastic recovery rate
70% or more