WO2018036504A1

WO2018036504A1 - Thermoplastic polyester elastomer foam precursor, foam and preparation method therefor

Info

Publication number: WO2018036504A1
Application number: PCT/CN2017/098595
Authority: WO
Inventors: 唐靖; 胡晓华; 李巡天
Original assignee: 唐靖
Priority date: 2016-08-24
Filing date: 2017-08-23
Publication date: 2018-03-01
Also published as: CN107641294A; CN107641294B; CN106189103A

Abstract

In order to overcome the problem that conventional thermoplastic polyester elastomers are difficult to foam, the present invention provides a thermoplastic polyester elastomer foam precursor, which contains the following components: a thermoplastic polyester elastomer, a melt viscosity modifier and a foam porous size stabilizer. Meanwhile, also disclosed in the present invention are a thermoplastic polyester foam and a preparation method therefor. The thermoplastic polyester foam provided in the present invention has the advantages of having a light weight, good outer appearance and excellent resilience, and is favorable for popularization and application.

Description

Precursor for foaming thermoplastic polyester elastomer, foam and preparation method thereof

The present application is based on the Chinese Patent No. 201610715351.X, entitled "A Thermoplastic Polyester Elastomeric Foam Particles and a Preparation Method", which is filed on August 24, 2016, and claims priority.

Technical field

The invention belongs to the technical field of thermoplastic elastomer foaming, and particularly relates to a thermoplastic polyester elastomer foaming precursor, a foam body and a preparation method thereof.

Background technique

Currently used foam plastics are polystyrene (PS) foam, polyethylene (PE) foam, polypropylene (PP) foam and the like. Styrofoam products are difficult to degrade and are prone to "white pollution" problems. The UN Environment Organization has decided to stop using PS foam products. Polyethylene foam has poor heat resistance and is not suitable for high temperature applications. Such products should have high surface hardness, easy to be crushed under pressure, and low resilience, which is difficult to be used for protective applications such as long-term buffer damping. Polyurethane (PU) soft and rigid foam materials are prone to residual isocyanate during foaming, which is harmful to human body, and thermosetting foaming materials cannot be recycled. VA foaming material, low temperature resistance, easy to melt above 70 degrees, and easy to decompose to produce acid gas, polluted air and surrounding environment, and has poor resilience after compression. Thermoplastic polyolefin elastomer (SEBS) and thermoplastic polyurethane elastomer (TPU) foaming materials have been used in some applications in the market in recent years, but their resistance to high temperature and low temperature is poor. The product is prone to yellow discoloration, limited application range, and compression back. Poor elasticity, easy to wrinkle after surface pressure or pressure release, weak tear resistance, easy hydrolysis and degradation, resulting in poor overall product performance, partial coloring is not good, easy to change under ultraviolet light, weak aging resistance, low production efficiency and high cost. Moldable foam beads of thermoplastic polyurethane have been disclosed in WO2007082838. However, the reported foamed thermoplastic polyurethane beads have the disadvantages of coarse cell structure, "wrinkles" on the surface of the particles, low product yield, and n-butane as a foaming agent in the foaming process, which is prone to environmental pollution. problem.

Although thermoplastic polyester elastomer (TPEE) has better mechanical properties than thermoplastic polyolefin elastomer (SEBS) and thermoplastic polyurethane elastomer (TPU), the structural characteristics of thermoplastic polyester elastomer determine its lower Melt viscosity and high melt flow are not conducive to foaming.

Summary of the invention

An object of the present invention is to provide a thermoplastic polyester elastomer foaming precursor, a foam, and a method for producing the same, which solve one or more of the above problems of the prior art.

The technical solution adopted by the present invention to solve the above technical problems is as follows:

A thermoplastic polyester elastomer foaming precursor is provided comprising the following components: a thermoplastic polyester elastomer, a melt melt viscosity modifier, and a cell size stabilizer.

Optionally, the melt melt viscosity modifier comprises one or a combination of ethylene-acrylate-glycidyl methacrylate and polystyrene-polyethylene-polybutene copolymer.

Optionally, the cell size stabilizer comprises one or more of dihydroxypropyl stearyl acid ester, sorbitan stearic acid monoester, and sorbitan palmitic acid monoester.

Optionally, the following components are included by weight: 100 parts of the thermoplastic polyester elastomer, 2 to 10 parts of the melt melt viscosity modifier, and 0.2 to 1.2 parts of the cell size stabilizer.

Optionally, the following components are included in parts by weight: 100 parts of the thermoplastic polyester elastomer, 2 to 10 parts of the melt melt viscosity modifier, and 2 to 12 parts of the cell size stabilizer.

Optionally, the thermoplastic polyester elastomer has a hardness in the range of Shore H25D to H45D.

Alternatively, the thermoplastic polyester elastomer foaming precursor is a granular structure having a smooth surface and a particle diameter of 0.2 to 8.0 mm.

Alternatively, the thermoplastic polyester elastomer foaming precursor has a melt flow rate of from 8 to 200 g/10 min.

Optionally, the thermoplastic polyester elastomer foaming precursor further comprises a UV stabilizer, and the UV stabilizer has a weight component of 0.1 to 0.5 parts.

A thermoplastic polyester foam comprising the following components: a thermoplastic polyester elastomer, a melt melt viscosity modifier, a cell size stabilizer, and a volatile blowing agent.

Optionally, the following components are included in parts by weight: 100 parts of thermoplastic polyester elastomer, 2 to 10 parts of melt melt viscosity modifier, 0.2 to 1.2 parts of cell size stabilizer, and volatile foaming agent 10 to 200 copies.

Optionally, the following components are included in parts by weight: 100 parts of thermoplastic polyester elastomer, 2 to 10 parts of melt melt viscosity modifier, 2 to 12 parts of cell size stabilizer, and volatile foaming agent 10 to 50 copies.

Alternatively, the volatile blowing agent is one or a combination of two of carbon dioxide and nitrogen.

Alternatively, the thermoplastic polyester elastomer is based on a polyether polyol having a molar mass of from 600 g/mol to 2500 g/mol and/or a polyester polyol having a molar mass of from 600 g/mol to 2500 g/mol.

Optionally, the thermoplastic polyester foam further comprises a UV stabilizer, and the UV stabilizer has a weight component of 0.1 to 0.5 parts.

Alternatively, the thermoplastic polyester foam has a density of 0.08 to 0.60 g/m ³ and a cell diameter of 10 to 800 μm.

A method for preparing a thermoplastic polyester foam as described above, comprising the steps of:

Precursor preparation: the thermoplastic polyester elastomer, the melt melt viscosity modifier and the cell stabilizer are uniformly mixed, and melt-cooled to prepare a thermoplastic polyester elastomer foaming precursor;

Foaming agent penetration: a thermoplastic polyester elastomer foaming precursor is added to a high pressure reaction vessel, a volatile foaming agent is added, and the temperature is raised to the softening point of the thermoplastic polyester elastomer foaming precursor, and the pressure is increased. The volatile foaming agent is in a supercritical state, and the heat preservation pressure is maintained;

Foaming: After the penetration of the foaming agent is completed, the pressure is lowered, and the thermoplastic polyester elastomer foaming precursor is foamed to form a thermoplastic polyester foam.

Optionally, the "precursor preparation" step comprises:

100 parts by weight of thermoplastic polyester elastomer, 2-10 parts of melt melt viscosity modifier, 0.2-1.2 parts of cell size stabilizer and 0.1-0.5 part of UV stabilizer are added to a high-mixer and mixed uniformly. The mixture is melt-kneaded by a twin-screw extruder, cooled, and then cut into pellets by an extruder strand or underwater pelletizing to obtain a thermoplastic polyester elastomer foaming precursor.

Optionally, in the “foaming agent permeation” step, the reaction temperature after the temperature rise is 100 to 175° C., and the holding time of the heat preservation is 2 to 3 hours.

The "foaming agent penetration" step includes:

Optionally, the thermoplastic polyester elastomer foaming precursor and water are added to the autoclave, the volatile foaming agent is added, and the aqueous suspension mixture is pressurized to raise the temperature to the thermoplastic polyester elastomer before foaming. The softening point of the body is pressurized to make the volatile foaming agent in a supercritical state, and the pressure is maintained.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. The present invention employs a thermoplastic polyester elastomer as a foaming body, and a thermoplastic melt elastomer is modified by adding a melt melt viscosity modifier and a cell size stabilizer to obtain a melt viscosity and a melt. The thermoplastic polyester elastomer foaming precursor with suitable flow rate is beneficial to ensure the dimensional stability of the foamed particles, and optimizes the elasticity and compression properties of the material, and significantly expands the temperature applicable range;

2. The invention has reasonable design, simple process, strong practicability, stable size, uniform cell diameter, high surface gloss and high product yield; the obtained foam product has small deformation, wide use temperature and shrinks with respect to the size of the mold. The rate is low, the dimensional stability is excellent, and the surface is beautiful; in addition, since the molded foam article has a small deformation, the aging time can be shortened, and the lower pressure water vapor can be used for molding processing, which is suitable for economical industrial production;

3. The invention can be used for toys filling, cushion filling, cushions, pillows, solid tires, etc. Under the condition of high temperature gas heating, it can be directly die-casting, injection molding, used for shock absorbing packaging materials, anti-collision protection parts, shock absorption. Mat (subway track cushion), precision instrument packaging, thermal insulation, sports protection products (sports midsole, insoles, helmets), outdoor protective equipment, floating equipment, baby stroller tires, etc.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects of the present invention more clear, the present invention will be further described in detail below with reference to the embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention discloses a thermoplastic polyester elastomer foaming precursor comprising the following components: a thermoplastic polyester elastomer, a melt melt viscosity modifier and a cell size stabilizer;

The cell size stabilizer is used to reduce the surface tension of the thermoplastic polyester elastomer and improve the foaming stability. In some embodiments, the cell size stabilizer comprises one or more of dihydroxypropyl octadecanoate, sorbitan stearate, and sorbitan palmitic monoester. The advantage is that a small amount of addition can stabilize the cell size after foaming in a relatively concentrated range, and reduce the problem that the cell size is too large to be easily broken. In some embodiments, the melt melt viscosity modifier comprises one or a combination of ethylene-acrylate-glycidyl methacrylate and polystyrene-polyethylene-polybutene copolymer. The advantage is that a small addition increases the viscosity of the melt and the melt viscosity value remains stable over a range of ±15 °C.

The thermoplastic polyester elastomer is a block type structural copolymer composed of two segments of soft and hard structure, and the soft segment is a segment formed of a non-crystalline polyether polyol or a polyester polyol. The segment determines the flexibility and elasticity of the material, and the hard segment is a segment formed of a relatively high hardness, crystalline polyparaphenylene terephthalate which determines the mechanical strength and stability of the material.

Preferably, a thermoplastic polyester elastomer having a molecular weight of 10,000 or more is used.

Preferably, the thermoplastic polyester elastomer is obtained by polymerizing terephthalic acid and a polyether polyol or a polyester polyol. In some embodiments, a chain extender such as 1,4-butanediol may also be added. .

In some embodiments of the invention, the melt melt viscosity modifier selects ethylene-acrylate-glycidyl methacrylate; in some embodiments of the invention, the melt melt viscosity modifier selects polyphenylene Ethylene-polyethylene-polybutene copolymer.

In some embodiments of the invention, by weight, 100 parts by weight of the thermoplastic polyester elastomer, 2 to 10 parts of the melt melt viscosity modifier, and 0.2 to 1.2 parts of the cell size stabilizer are included.

In some embodiments of the invention, by weight, 100 parts by weight of the thermoplastic polyester elastomer, 2 to 10 parts of the melt melt viscosity modifier, and 2 to 12 parts of the cell size stabilizer are included.

When the content of the melt melt viscosity modifier is too small, the melt viscosity adjustment effect is poor, which affects the foam molding of the foam; when the content of the melt melt viscosity modifier is too large, The melt viscosity of the obtained thermoplastic polyester elastomer foaming precursor is too large, which is also disadvantageous for foaming.

In some embodiments of the invention, the thermoplastic polyester elastomer has a hardness in the range of Shore H25D to H45D, preferably H28D to H45D.

The advantage is that the thermoplastic polyester elastomer has a melting point of not higher than 175 ° C in this hardness range, which is advantageous for stably adjusting the softening temperature in the pellet high pressure reactor.

In some embodiments of the invention, the thermoplastic polyester elastomer is based on a polyether polyol having a molar mass of from 600 g/mol to 2500 g/mol.

Alternatively, the thermoplastic polyester elastomer is based on a polyester polyol having a molar mass of from 600 g/mol to 2500 g/mol, or a polyether polyol of from 600 g/mol to 2500 g/mol and from 600 g/mol to 2500 g/mol. Polyester polyol is mixed.

In some embodiments of the present invention, the thermoplastic polyester elastomer foaming precursor is a smooth, granular structure having a particle diameter of 0.2 to 8.0 mm, and more preferably a particle diameter of 2 to 5 mm.

The thermoplastic polyester elastomer foaming precursor has a smooth surface-like granular structure. The inventors have found through many experiments that when the thermoplastic polyester elastomer foaming precursor is foamed, The angular particles tend to cause uneven penetration of the foaming agent, resulting in uneven cell diameter and cell density, and it is easy to cause cell breakage at the angular position during foaming, affecting the expansion ratio of the particles and the appearance of the product. At the same time, it was found that when foaming with thermoplastic polyester elastomer, the smooth granular structure of the surface is favorable for the penetration of the foaming agent, and the smooth granular structure of the surface may be an ellipsoidal shape, a drop shape or a spherical structure. When the particle diameter is too large, it will affect the full penetration of the foaming agent and affect the expansion. rate.

In some embodiments of the invention, the thermoplastic polyester elastomer foaming precursor has a melt flow rate of from 8 to 200 g/10 min.

Melt flow rate (MI) test conditions: ISO 1133 230 ° C / 2.16 kg, measured at 230 ° C constant temperature, load 2.16 kg conditions to determine the melt flow rate, the unit is g/10min, the time flowing out within 10 minutes The weight in grams of the polymer.

ISO 1133: "Plastics - Thermoplastic Melt Mass Flow Rate (MFR) and Melt Volume Flow Rate (MVR) Determination" Standard Method.

In some embodiments of the invention, the thermoplastic polyester elastomer foaming precursor further comprises a UV stabilizer.

The UV stabilizer is used to increase the stability of the thermoplastic polyester elastomer under ultraviolet irradiation.

The UV stabilizer has a weight component of 0.1 to 0.5 parts by weight.

In some embodiments of the invention, the UV stabilizer is poly(dimethyl 4-hydroxy-2,2,6,6-tetramethyl-1-azetaneethanol).

In some embodiments of the present invention, the thermoplastic polyester elastomer foaming precursor component further comprises an auxiliary agent, which is a flame retardant, an antistatic agent, a pigment, a hydrolysis inhibitor, and an inorganic filler. Or organic filler. The amount of the adjuvant added is determined according to actual use requirements. The advantage is that the thermoplastic polyester elastomer modified material foamed particles can be adapted for different applications.

If it is desired to apply the thermoplastic polyester elastomer foaming precursor to a safety footwear product or to a precision instrument, an antistatic agent may be added to the component to lower the surface resistance of the product. Adding an antistatic agent can speed up the electrostatic discharge of the contact surface and avoid the risk of damage to the instrument or the formation of sparks due to static buildup.

If it is desired to apply the thermoplastic polyester elastomer foaming precursor to the aspect in which color is required, such as the production of a sole and sports equipment, a pigment may be added to the component, which may be a toner or a color paste. Adding pigments to the components can obtain foamed particles of thermoplastic polyester elastomer modified materials with preset colors, and can be made into colorful products, which can help to mark different products and improve the aesthetics of the products.

The present invention also discloses a thermoplastic polyester foam comprising the following components: a thermoplastic polyester elastomer, a melt melt viscosity modifier, a cell size stabilizer, and a volatile foaming agent.

The thermoplastic polyester foam can be prepared by adding a volatile foaming agent to the thermoplastic polyester elastomer foaming precursor as described above.

The thermoplastic polyester foam provided by the invention has excellent applicability in high temperature and low temperature environments, The foaming temperature range is wide, the yield is high, and the finished product has a wide processing temperature range and can be used over a very wide temperature range. It has excellent mechanical strength, water resistance, oil resistance and chemical resistance. It has high color retention under UV light, rich color, environmental friendliness and recyclability.

In some embodiments of the present invention, the following components are included in parts by weight: 100 parts of thermoplastic polyester elastomer, 2 to 10 parts of melt melt viscosity modifier, 0.2 to 1.2 parts of cell size stabilizer, and volatility The foaming agent is 10 to 200 parts.

In some embodiments of the present invention, the following components are included in parts by weight: 100 parts of thermoplastic polyester elastomer, 2 to 10 parts of melt melt viscosity modifier, 2 to 12 parts of cell size stabilizer, and volatility 10 to 50 parts of foaming agent.

In some embodiments of the invention, the volatile blowing agent is one or a combination of carbon dioxide and nitrogen, preferably carbon dioxide. The advantage is that the two gases are easy to obtain and low in price, have no toxicity and flammable and explosive danger, and have no environmental pollution. The operating temperatures of the two gas foaming processes are also favorable for the foaming stable operation of the high pressure reactor, wherein The use of carbon dioxide also contributes to the fixation of greenhouse gases and reduces the greenhouse effect.

In some embodiments of the invention, the melt melt viscosity modifier comprises one or both combinations of ethylene-acrylate-glycidyl methacrylate and polystyrene-polyethylene-polybutene copolymer.

In some embodiments of the invention, the cell size stabilizer comprises one of dihydroxypropyl octadecanoate, sorbitan stearate, and sorbitan palmitic monoester or A variety.

In some embodiments of the invention, the thermoplastic polyester elastomer is based on a polyether polyol having a molar mass of from 600 g/mol to 2500 g/mol and/or a polyester polyol having a molar mass of from 600 g/mol to 2500 g/mol.

In some embodiments of the invention, the thermoplastic polyester elastomer has a hardness in the range of Shore H25D to H45D.

In some embodiments of the invention, the thermoplastic polyester foam further comprises a UV stabilizer having a weight component of from 0.1 to 0.5 parts by weight. In some embodiments of the invention, the thermoplastic polyester foam has a density of from 0.08 to 0.60 g/m ³ and a cell diameter of from 10 to 800 μm.

The invention also discloses a preparation method of a thermoplastic polyester foam as described above, comprising the following steps:

Precursor preparation: 100 parts by weight of thermoplastic polyester elastomer, 2-10 parts of melt melt viscosity modifier, 0.2-1.2 parts of cell size stabilizer and 0.1-0.5 parts of UV stabilizer are added to the high-mixer Mix evenly, melt and knead by twin-screw extruder, cool and then pass through extruder bar or underwater pelletizing The pellets were cut into pellets to obtain a precursor for foaming a thermoplastic polyester elastomer.

In some embodiments of the present invention, the preparation of the particles by means of underwater pelletizing is preferably carried out. When the underwater pelletizing is used, the pressure of the water acts to form the droplets, and the edges of the particles are reduced, thereby facilitating the improvement. Subsequent foaming effect.

In some embodiments of the present invention, the thermoplastic polyester elastomer foaming precursor may also be extruded through an extruder to form different shapes depending on the shape of the thermoplastic polyester foam.

Foaming agent penetration: The thermoplastic polyester elastomer foaming precursor is added to the autoclave, the volatile foaming agent is added, and the temperature is raised to the softening point of the thermoplastic polyester elastomer foaming precursor, and the reaction temperature after the temperature rise The pressure foaming agent is in a supercritical state at a temperature of 100 to 175 ° C, and the pressure is maintained for 2 to 3 hours.

Foaming: After the penetration of the foaming agent is completed, the pressure is lowered, and the solubility of the foaming agent in the thermoplastic polyester elastomer foaming precursor is lowered due to the pressure reduction, thereby producing in the thermoplastic polyester elastomer foaming precursor. The expansion action, the thermoplastic polyester elastomer foaming precursor is foamed to form a thermoplastic polyester foam.

As an alternative embodiment of the invention, the "foaming agent penetration" step comprises:

The thermoplastic polyester elastomer foaming precursor and water are added to the autoclave, a volatile foaming agent is added, and the mixture is pressurized to form an aqueous suspension mixture, and the temperature is raised to the softening point of the thermoplastic polyester elastomer foaming precursor. Pressurizing the volatile blowing agent in a supercritical state, and maintaining the pressure.

The invention is further illustrated by the following examples.

The physical indices of the thermoplastic polyester elastomer particulate material used in the following examples are:

The above thermoplastic polyester elastomer granular material can be produced by the company produced by Jiangyin and Chuang Elastomer New Material Technology Co., Ltd., produced by Taiwan Changchun Chemical Co., Ltd., produced by SK Corporation of Korea, DuPont of the United States, and the like.

Plastic polyester elastomer foamed particle density reference index: 0.08-0.60g/cm ³ . The density of EVA resin products widely used in the market is about 0.27 g/cm ³ , so the expected value of the foaming material in the footwear industry is less than or equal to the density, and the density is higher than 0.3 g/cm ³ to 0.6 g/cm ^{3 .} The products are used for other applications with higher load-bearing loads. For products higher than 0.7g/cm ³ , foaming granules can be prepared by a lower cost foaming method, which will not be elaborated here.

The uniformity of the cell diameter directly affects the performance of the product. If the diameter of the cell is too large, it may cause cooling or collapse during use, which may affect the function and appearance. If the cell diameter is too small, the degree of foaming is low or not foaming, and the density of foamed particles of plastic polyester elastomer cannot be effectively reduced. . The invention has been experimentally verified that the foamed particles of the thermoplastic polyester elastomer modified material have excellent cell diameter in the range of 10 to 800 μm (preferably 10 to 100 μm), high surface gloss, good elasticity of the foamed particles, and good Industrial application prospects.

Example 1

a) 100 kg of thermoplastic polyester elastomer particles A, 5 kg of ethylene-acrylate-glycidyl methacrylate, 8 kg of sorbitan monostearate, 0.25 kg of UV stabilizer were added to the mixer. After mixing, the mixture was introduced into a twin-screw extruder through a hopper for melt-kneading, and the melt flow rate was measured under the conditions of a constant temperature of 230 ° C and a load of 8.7 kg. The melt-kneaded material conforming to the melt flow rate index is extruded into a strip shape from a die hole having an extruder diameter of 1.5 mm, cooled and formed in a cooling water tank of about 5 m length, and cut into 2.5 mm by a pelletizer. Long particles, thereby obtaining a thermoplastic polyester elastomer foaming precursor.

b) 100 kg of the obtained thermoplastic polyester elastomer foaming precursor and 500 kg of purified water were mixed and added to the autoclave to form an aqueous suspension mixture. While stirring, 30 kg of a carbon dioxide volatile blowing agent was added, and the autoclave was heated to 155 °C.

c) under the condition of thorough mixing and heating, the water suspension mixture is kept at this temperature for 3 hours, and finally the bottom end discharge valve of the autoclave is opened, and the mixture in the autoclave is discharged to a normal pressure environment, thereby obtaining Thermoplastic polyester elastomer foamed granules.

The melt flow rate obtained in this example was 130 g/10 min, the density of the thermoplastic polyester elastomer foamed particles was 0.25 g/cm ³ , and the average diameter of the foamed cells was 270 μm.

Table 1 is an example of the preparation of the thermoplastic polyester elastomer-modified material foamed granules of Example 1 and other methods similar or similar to those of Example 1, thermoplastic polyester elastomer particles, melt melt viscosity modifier, hair The weight of the cell size stabilizer, the UV stabilizer and the blowing agent, and the melt flow rate and the high pressure reactor temperature, the density of the foamed particles of the thermoplastic polyester elastomer-modified material and the average diameter of the foamed cells.

It can be seen from Table 1 that the thermoplastic polyester elastomer modified material foaming granules prepared in Examples 1-18 have the required composition: the thermoplastic polyester elastomer content is 100 parts, and the melt melt viscosity modifier content ranges from 2 to 10 parts, the cell size stabilizer content ranges from 2 to 10 parts, the UV stabilizer content ranges from 0.1 to 0.5 parts, and the volatile blowing agent content ranges from 10 to 50 parts. Therefore, the melt flow rate values measured after melt-kneading were all in the range of 40 to 200 g/10 min. The temperature of the high temperature reactor is controlled between 110 and 175 ° C. The mixed suspension is stably adjusted in this temperature range to uniformly foam. The density of the foamed particles of the plastic polyester elastomer modified material is 0.08-0.30g. /cm ³ interval; the average diameter of the foamed holes is within 250-800 μm.

Examples 19-28, because the melt melting regulator portion, the high temperature reactor temperature is too low or too high, the melt flow rate is too high or too low, so it is not possible to stably heat the mixed suspension of particles and water. To the softening temperature of the particles suitable for foaming, the thermoplastic polyester elastomer foamed particles could not be formed.

Example 29

a) 100 kg of thermoplastic polyester elastomer particles A, 5 kg of ethylene-acrylate-glycidyl methacrylate, 0.2 kg of sorbitan monostearate, 0.25 kg of UV stabilizer were added to the mixer. After mixing, the mixture was introduced into a twin-screw extruder through a hopper for melt-kneading, and the melt flow rate was measured at a constant temperature of 230 ° C under a load of 2.16 kg. The melt kneaded product conforming to the melt flow rate index was introduced from an extruder into an underwater pelletizer, and cut into ellipsoidal particles having a diameter of 2.5 mm to obtain a thermoplastic polyester elastomer foaming precursor.

b) 100 kg of the obtained thermoplastic polyester elastomer foaming precursor was added to 50 kg of a carbon dioxide volatile foaming agent, and added to a high pressure reaction vessel to form a suspension mixture. The autoclave was heated to 165 ° C while stirring.

The melt flow rate obtained in this example was 8 g/10 min, the density of the thermoplastic polyester elastomer foamed beads was 0.22 g/cm ³ , and the average diameter of the foamed cells was 70 μm.

Table 2 is an example of the preparation of the thermoplastic polyester elastomer-modified material expanded particles in the same manner as or in the same manner as in Example 29, in Example 29, the thermoplastic polyester elastomer particles, the melt melt viscosity modifier, and the hair The weight of the cell size stabilizer, the UV stabilizer and the blowing agent, and the melt flow rate and the high pressure reactor temperature, the density of the foamed particles of the thermoplastic polyester elastomer-modified material and the average diameter of the foamed cells.

It can be seen from Table 2 that the thermoplastic polyester elastomer modified material foaming granules prepared in Examples 29-36 have the required composition: the thermoplastic polyester elastomer content is 100 parts, and the melt melt viscosity modifier content ranges from 2 to 2 10 parts, the cell size stabilizer content ranges from 0.2 to 1.2 parts, the UV stabilizer content ranges from 0.1 to 0.5 parts, and the volatile blowing agent content ranges from 10 to 200 parts. Therefore, the melt flow rate values measured after melt-kneading were all in the range of 8 to 40 g/10 min. The temperature of the high temperature reactor is controlled between 110 and 175 ° C. The mixed suspension is stably adjusted in this temperature range to uniformly foam. The density of the foamed particles of the plastic polyester elastomer modified material is 0.08-0.60g. /cm ³ interval; the average diameter of the foamed holes is within 10 - 800 μm.

Therefore, the present invention requires that the thermoplastic polyester elastomer of the host material has a hardness between Shore H28D and H45D, and the thermoplastic polyester elastomer itself has a melting point of not higher than 175 ° C, and the melt flow is adjusted by using a melt melt conditioner. The rate reaches the target range, which stabilizes the effective foaming, ensures the dimensional stability of the foamed particles, and optimizes the elastic and compressive properties of the material and the range of the post-processing temperature range, while significantly expanding the temperature range.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

A thermoplastic polyester elastomer foaming precursor comprising the following components: a thermoplastic polyester elastomer, a melt melt viscosity modifier, and a cell size stabilizer.
The thermoplastic polyester elastomer foaming precursor according to claim 1, wherein the melt melt viscosity modifier comprises ethylene-acrylate-glycidyl methacrylate and polystyrene-polyethylene- One or two combinations of polybutene copolymers.
The thermoplastic polyester elastomer foaming precursor according to claim 1, wherein the cell size stabilizer comprises dihydroxypropyl octadecanoate, sorbitan stearic acid monoester, and One or more of sorbitan palmitic acid monoesters.
The thermoplastic polyester elastomer foaming precursor according to claim 1, which comprises, by weight, 100 parts of a thermoplastic polyester elastomer and 2 to 10 parts of a melt melt viscosity modifier. The cell size stabilizer is 0.2 to 1.2 parts.
The thermoplastic polyester elastomer foaming precursor according to claim 1, which comprises, by weight, 100 parts of a thermoplastic polyester elastomer and 2 to 10 parts of a melt melt viscosity modifier. 2 to 12 parts of cell size stabilizer.
The thermoplastic polyester elastomer foaming precursor according to claim 1, wherein the thermoplastic polyester elastomer has a hardness ranging from Shore H25D to H45D.
The thermoplastic polyester elastomer foaming precursor according to claim 1, wherein the thermoplastic polyester elastomer foaming precursor is a smooth granular structure having a particle diameter of 0.2 to 8.0 mm. .
The thermoplastic polyester elastomer foaming precursor according to claim 1, wherein the thermoplastic polyester elastomer foaming precursor has a melt flow rate of from 8 to 200 g/10 min.
The thermoplastic polyester elastomer foaming precursor according to claim 4, wherein The thermoplastic polyester elastomer foaming precursor further includes a UV stabilizer, and the UV stabilizer has a weight component of 0.1 to 0.5 parts.
A thermoplastic polyester foam comprising the following components: a thermoplastic polyester elastomer, a melt melt viscosity modifier, a cell size stabilizer, and a volatile foaming agent.
The thermoplastic polyester foam according to claim 10, which comprises, by weight, 100 parts of a thermoplastic polyester elastomer, 2 to 10 parts of a melt melt viscosity modifier, and a cell size. The stabilizer is 0.2 to 1.2 parts, and the volatile foaming agent is 10 to 200 parts.
The thermoplastic polyester foam according to claim 10, which comprises, by weight, 100 parts of a thermoplastic polyester elastomer, 2 to 10 parts of a melt melt viscosity modifier, and a cell size. 2 to 12 parts of stabilizer and 10 to 50 parts of volatile foaming agent.
The thermoplastic polyester foam according to claim 10, wherein the volatile blowing agent is one or a combination of two of carbon dioxide and nitrogen.
The thermoplastic polyester foam according to claim 10, wherein said melt melt viscosity modifier comprises ethylene-acrylate-glycidyl methacrylate and polystyrene-polyethylene-polybutene copolymerization. One or two combinations of substances.
The thermoplastic polyester foam according to claim 10, wherein said cell size stabilizer comprises dihydroxypropyl octadecanoate, sorbitan stearate monoester and sorbitan One or more of palmitic acid monoesters.
The thermoplastic polyester foam according to claim 10, wherein the thermoplastic polyester elastomer is based on a polyether polyol having a molar mass of from 600 g/mol to 2500 g/mol and/or a molar mass of 600 g/mol. 2500 g/mol of polyester polyol.
The thermoplastic polyester foam according to claim 10, wherein the thermoplastic polyester elastomer has a hardness ranging from Shore H25D to H45D.
The thermoplastic polyester foam according to claim 11, wherein the thermoplastic polyester foam further comprises a UV stabilizer, and the weight component of the UV stabilizer is 0.1 to 0.5 part.
The thermoplastic polyester foam according to claim 10, wherein the thermoplastic polyester foam has a density of 0.08 to 0.60 g/m 3 and a cell diameter of 10 to 800 μm.
A method of preparing a thermoplastic polyester foam according to any one of claims 10 to 19, which comprises the steps of:

Precursor preparation: the thermoplastic polyester elastomer, the melt melt viscosity modifier and the cell stabilizer are uniformly mixed, and melt-cooled to prepare a thermoplastic polyester elastomer foaming precursor;

Foaming agent penetration: a thermoplastic polyester elastomer foaming precursor is added to a high pressure reaction vessel, a volatile foaming agent is added, and the temperature is raised to the softening point of the thermoplastic polyester elastomer foaming precursor, and the pressure is increased. The volatile foaming agent is in a supercritical state, and the heat preservation pressure is maintained;

Foaming: After the penetration of the foaming agent is completed, the pressure is lowered, and the thermoplastic polyester elastomer foaming precursor is foamed to form a thermoplastic polyester foam.
The method of preparing a thermoplastic polyester foam according to claim 20, wherein the "precursor preparation" step comprises:

100 parts by weight of thermoplastic polyester elastomer, 2-10 parts of melt melt viscosity modifier, 0.2-1.2 parts of cell size stabilizer and 0.1-0.5 part of UV stabilizer are added to a high-mixer and mixed uniformly. The mixture is melt-kneaded by a twin-screw extruder, cooled, and then cut into pellets by an extruder strand or underwater pelletizing to obtain a thermoplastic polyester elastomer foaming precursor.
The method for preparing a thermoplastic polyester foam according to claim 20, wherein in the "foaming agent permeation" step, the reaction temperature after the temperature rise is 100 to 175 ° C, and the time for holding and holding the pressure is 2 ~3 hours.
The method of preparing a thermoplastic polyester foam according to claim 20, wherein the "foaming agent penetration" step comprises:

The thermoplastic polyester elastomer foaming precursor and water are added to the autoclave, a volatile foaming agent is added, and the mixture is pressurized to form an aqueous suspension mixture, and the temperature is raised to the softening point of the thermoplastic polyester elastomer foaming precursor. Pressurizing the volatile blowing agent in a supercritical state, and maintaining the pressure.