JPS58111837A - Non-crosslinked high-density polyethylene pre-expanded particle and preparation of same - Google Patents

Abstract

PURPOSE:To prepare the titled pre-expanded particle with excellent weatherability, thermal resistance, tensile strength, etc., by dispersing in a dispersing medium a specified non-crosslinked high-density PE particle impregnated with a volatile foaming agent, and releasing the dispersion from a high-temp. high- press. atmosphere to a low-press. atomsphere. CONSTITUTION:100pts.wt. non-crosslinked high-density PE particle (A), Vicat softening point >=115 deg.C and density of 0.950-0.968g/cm<2>, 5-40pts.wt. volatile foaming agent (B) (e.g., dichlorodifluoromethane), 0.01-10pts.wt. dispersant (C) (e.g., particulate Al2O3), and dispersing medium (D) (e.g., water) are charged in a closed vessel, which is heated at temp. in a range from 10 deg.C lower than the Vicat softening point of component A to 10 deg.C higher than the m.p. of component A, and component A is impregnated with component B while components A, B and C are dispersed in component D. Then the mixt. is released into a low- press. atmosphere by opening one end of the vessel, yielding a non-crosslinked high-density PE pre-poamed particle, bulk density of 0.01-0.3g/cm<3>, average cell diameter of 20-500mu and closed cell content >=65%.

Description

[Detailed description of the invention] The present invention has no crosslinking height 1! degree polyethylene reserve-fIIA'
This invention relates to IIj1 child and its manufacturing method.

Conventionally, a rigid bead forming method using pre-expanded particles has been used as a method for obtaining a foamed polyethylene resin body. However, if the pre-expanded particles used in SoC are not cross-linked, it is difficult to obtain a powerful body with high power generation.
Again j! The shoe body has a significantly large rounding capacity and has not yet been put to practical use. Soni II * Bridge bridge and circle preliminary foam particles.
However, since it consumes chemicals and energy and is difficult to reuse, a method using uncrosslinked preliminary M111 has been eagerly awaited.

The purpose of the present invention is to provide a non-crosslinked high-density polyethylene pre-fired foam and a method for producing the same. We succeeded in developing non-crosslinked high-strength polyethylene pre-foamed particles with excellent properties such as durability, tear strength, self-fatigue resistance, compression resistance, and internal strength properties, as well as a process for producing the same, leading to the completion of the present invention.
)Big.

That is, one shot *a, Vicat softening point 115℃ or higher = 0
．． Non-crosslinked high-density polyethylene with a temperature exceeding 9 SOj/-) 11 bulk 11 degrees 0.01-0.31/al.

The gist is non-crosslinked, high-density polyethylene preformed particles having an average air density of 111 @ 20 s to S OOμ+ lk and a bubble rate of 65 or more. Honsha Tsutomu's one-of-a-kind Otatami Uhiro Vicat Softening point 115℃ or higher, 0.950II
Incorporating a volatile blowing agent into a non-crosslinked high-texture polyethylene shaft with a degree of O exceeding /- II, in a 1111 vessel
A process of dispersing 6 g particles into dispersion m, and a helmet W1411
Vessel 01111! One end of the container is opened while maintaining the temperature between 10°C below the Vicat softening point of the particles and 10°C above the melting point, and the particles are separated by tm,=t″l″.
IIIKmFIIn! DffiBl) $111! L
The present invention relates to a method for producing pre-fired bran bran of non-crosslinked high-texture polyethylene, which is characterized by a step of TKlttl.

Substrate resin used in this invention Vicat softening point 115℃
The above is a non-crosslinked high-texture polyethylene (hereinafter referred to as non-crosslinked HDP) with a strength exceeding 0.950 j/at.

The Vicat softening point is 1115'c, the internal moldability is poor, and the physical properties of the prestigious product are poor. If the degree is less than 0, *s o I/d, pre-foaming will be difficult. Preferred range i for Vicat softening point 04I! 41KtFft of 〉9m degree above 141118℃
L range is O,il 50-0.96 II I/
It is d.

The non-crosslinked HDPK of the present invention is
It can be made into pelletized spherical particles with 0% filtration and may contain additives such as antioxidants and ultraviolet 1I absorbers.

Examples of volatile 111iIll agents used in the present invention include evafuropane, butane, pentane, hequinane,
Aliphatic hydrocarbon groups such as heptane, cyclobutane, V/I2 pentane, etc., and trichloro7μlomethane, Ditarology 70
Halogenated hydrocarbons exemplified by lomethane, di-7-loethane, methyl chloride, ethyl tetralide, methylene fulleride and the like are used. this! The amount of foaming agent added varies depending on the amount of wrinkle foaming agent (0 ml, 1 liter) and the degree of foaming, but is usually 5 to 40 parts by weight.

In the method for producing #0 non-crosslinked HDPE pre-expanded particles of the present invention,
Contains non-crosslinked HDPI @ child Klf foaming agent,
At this time, 41IIIciIN was not determined, and tJ6HD
A foaming agent may be contained in the PK yoshi, and the HDI'l* child containing this foaming agent may be placed in a container and dispersed in the closed container, or alternatively, the HDPE yoshi and the foaming agent may be dispersed in the closed container. The foaming agent may be added to the HDPΣ particles while dispersing the agent in the scissor spring container at a dispersion ratio of 1/I& in the scissor spring container. The particles were brought to a predetermined temperature in a closed round tube container with 11 ml of aliquot. The foaming agent may be contained in the particles while the foaming agent is placed in a closed container and the particles and the foaming agent are dispersed. Yes.

The temperature at which the foaming agent is contained in the particles is also optional.
, 41.

In the method of the present invention, HDPI particles and a volatile blowing agent are mixed separately or after the volatile blowing agent is incorporated into HDPK particles and then thoroughly dispersed. This can be achieved by using oxidized titanium oxide, basic danesium legate, basic zinc carbonate, calcium carbonate, etc.

The amount of this dispersant added is usually enough to disperse 1 HDPK particle, 1 particle, 10 particles, a melting point of 21C or higher, and an HLI value of 1.
~100 organic compound 1 such as stearic acid amide etc. 5
It can also be added in an amount of less than part by weight. Heavy nine dispersion medium is HDP
Any medium may be used as long as it does not dissolve the particles.For example, one or more of water, ethylene glycol, glycerin, methanol, ethanol, etc. may be used.

Water is usually preferred.

Using the pre-foaming method of the present invention, one end of the container is heated and hardened.
PKf11 and the dispersion medium are placed in the container at the same time) at low pressure.
1As is released into the atmosphere, but at this time O11 degree HiroHDPΣ
The temperature ranges from 311 G°C lower than the Vicat softening point of the particles to 011-10°C higher than the Vicat softening point. When the temperature is lower than the Vicat softening point Jllo, HIRO hardly generates electricity, and when the temperature exceeds the VICAT softening point J) 10℃ higher, the closed cell ratio decreases markedly, and the open cell and '1k> machines target strength decreases. Particularly preferred range of foaming temperature
The temperature ranges from 5°C lower than the Vicat softening point to 8°C higher than the Vicat softening point. In this case, the pressure may be greater than or equal to the vapor pressure of the volatile blowing agent and less than or equal to the vapor pressure of the volatile blowing agent, and the atmosphere in which the blowing agent is discharged is selected to be at normal pressure.

The pre-expanded particles of the present invention obtained by the above-described method have a ratio of 0.01 to 0.311/al and a closed cell ratio of 6.
The average bubble diameter is 20 to 500μ.

When the bulkiness is less than 0.01J/-, the shape of the particle is easily distorted by 1G<, and when the bulkiness exceeds 19O,3,9/-, the shape of the particle is easily distorted. (a), but the shape of the strips becomes uneven. Bulk Il/IK preferred range m line GG
15-0.15j/j. Closed cell ratio is 45596
The company 1 foam in the pigeon house of Mino, -... the child is distorted Keel easy <, 1
The compressive elasticity decreases. A preferable range for the closed cell ratio of 041 is 75 or more. If the average air ms is less than 20 voices, the shape of the pigeon house will be distorted by 11 degrees, and the mechanical strength will be reduced, and if the average air ms is more than 9 secondsOOμ, the internal strength will be poor.
It is difficult to obtain a good laminated body, and even if a laminated body is obtained, the IN and IN sides are hard and convex and dull. The preferred range for the average bubble size 11041 is 50 to 400μ.

The particle size of the pre-expanded particles is not particularly limited, but is preferably from 5 to 20 mm from the viewpoint of fluidity.

The pre-expanded particles of the present invention as described above are usually aged for a predetermined period of time at room temperature and normal pressure.(1) Then, if necessary, an inorganic gas (prepared with an inorganic gas and a volatile blowing agent) is used at a predetermined pressure.
Matured under pressure for a predetermined period of time.

The nine pre-generated particles are filled into the gold layer with the internal pressure applied as described above, and the normal water vapor pressure is 1.2 to L S Ill/aj (G
) to obtain a foamed lid body.

The Hatsuikei shoe body obtained as described above is, for example, a Bao II material.

Can be used for buffer materials, heat-insulating food containers, floating 111N, etc.

As explained above, the preliminary lithium-ion weather resistance, heat resistance, tear strength, layer-imprint resistance, Im compressive elasticity, I
The foamed particles obtained using these pre-expanded particles have excellent properties such as the above-mentioned properties. According to Kuhonshu@, non-crosslinked HDP
It is possible to obtain pre-expanded particles with excellent properties from I@, and by eliminating the need for a cross-linking process, it is possible to simplify the process (IiO), and it does not consume energy, chemicals, etc. It has various advantages, such as being able to reduce costs because it requires only a few steps, and furthermore, it can be rolled up and reused without crosslinking.

Hereinafter, the present invention will be explained in more detail by referring to Example II and Comparative Examples.

Example 1~! sI- and Comparative Examples 1 to 9 All true roundness, Vicat softening point and melting point 100 parts of non-crosslinked HDPE, 25 parts by weight of Gidaro' Schiffromethane, fine granular aluminum oxide O9
Put s parts by weight and 300 parts by weight of water into the autotaleve,
While stirring, raise the temperature in the container to 110°C, and keep the pressure at 20 to 6 kf/j (G) K.
〇 Firstly, release it under the atmosphere and cause it to foam to obtain the gently O pre-expanded particles shown in the first example. As a comparative example, low density polyethylene (hereinafter referred to as LDPK), cross-linked LDPK
Pre-expanded particles shown in Table 1 were prepared in the same manner as in the examples using non-crosslinked HDPE which is outside the scope of the present invention.

The obtained pre-expanded particles were left open for 41 hours at room temperature and pressure, and then filled into a ll1Fl intimidator and zs k#/-(G
) Matured under pressure for 48 hours in air at -35°C. The pre-expanded particles are then filled into the gold m and each precious metal has an OSm above the Vicat softening point of 1. z ~s, s k#/ai (Q)
Heating it with 0 water vapor will give you a powerful body in one shot. Various physical property tests were conducted on the pre-expanded particles and the resulting Kuaike stratified body. Results first! IIIK shown. Yes, average bubble value O
Scooping is cutting using an electron microscope! Act by observing.

Table 2 @1 ---- 'l engineering f *) - fi - f2 G Processed for 04, 111 coloring, deformation 1 elasticity! Judge by 10 changes.

◎ - Almost no coloring or deformation, elasticity 0 ---- Coloring, some deformation ■ - Elasticity 8-1 Coloring, deformation observed, 1 elasticity decrease x---- Coloring, Severe deformation was observed and 2. Significant decrease in elasticity *2 - In a gear oven at 1000 hrs.

Q7 --- Coloring, deformation 1 Almost no change in elasticity O - Coloring, some deformation is observed, but elasticity Δ --- Coloring, deformation is observed, and elasticity decreases × --- Coloring, Significant deformation was observed and the elasticity decreased.

0-11 Oal 1 or more fractures o -s o o -s o o Fractures at less than 6 Δ--
Fractured at less than 100 to SOO times

Q-7kl/10■ Width exceeding Q--3 #/10■- 7kIi/16■ Body Δ
---1 to 5P/10-31I#/10 ■Width X--1 Yu/10■@ less than Australia 5---Using Tensilon, the maximum stress is 4klI/- at a moderate distance of 10m/-. After compression and stress removal, elastic recovery from strain was established.

Q　------Graduation of 955 or more ○---85 to less than 95 - recovery △-75~85s unconcentrated recovery X -- less than 75 arrogant Qin 6 --- Judge according to the following O criteria.

〇-Narm*Good 0-・-Weiten Tatami Street Δ−−−− *Full of cover JIILtK thousand occurrences

Claims (2)

[Claims] (1) Vicat softening point 115℃ or higher, O59601
Unbridged height exceeding 1/d! If tb from polyethylene, bulk * degree o) ox ~ 0.311/aJ, average cell diameter 20μ ~ 500711. lII Non-crosslinked high 11 & polyethylene preliminary Oreike particles with 4111 having a bubble rate of 6516 or more. (2) Vicat softening point 115℃ or higher, o, e s
A step of incorporating a volatile blowing agent into non-crosslinked high-strength polyethylene particles with a size exceeding 7.o g. While maintaining the temperature within the range from i** 10°C lower than the Vicat softening point to 10°C higher than the Vicat softening point, one end of the container is released and the originating particles and dispersion plot are simultaneously placed inside the container) at low pressure. Ot- Non-crosslinked high IIt polyethylene pre-expanded particle OII method in which the step of releasing into the atmosphere and the p layer are ll1Ik.