JPS60161438A - Expansible resin coated particle - Google Patents

Abstract

PURPOSE:Expansible resin coated particles, obtained by coating aggregate particles with a specific expansible resin composition, and capable of giving uniform expanded articles having improved dimensional stability and heat insulating effect. CONSTITUTION:Expansible resin coated particles obtained by coating (A) 1l volume of aggregate particles which are organic particles, e.g. expanded resol type phenolic resin particles, or inorganic particles, e.g. perlite or silas balloons, or a mixture thereof with (B) >=5g, preferably 15-500g expansible resin composition consisting essentially of (i) 100pts.wt. movable type phenolic resin precondensate, preferably a condensate of phenol with formaldehyde, (ii) 1- 50pts.wt. decomposition type foaming agent, e.g. N,N'-dinitrosopentamethylenetetramine, and (iii) 1-30pts.wt. curing agent, e.g. hexamethylenetetramine.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to foamable particles in which the surface of granular aggregate is coated with a foamable resin composition.

Conventionally, foamable resin-coated particles made by mixing the initial combination of Novolakya Phenol Vl 14 and the required amount of decomposed blowing agent and hardening agent are usually used in powder form, and the size of the powder is 100 mesh or more. The bulk specific gravity is also usually 1 or less. This composition and other particles are mixed to create a phenol.
A molded body of μ resin was obtained.

If the particle size is not larger than II and the bulk specific gravity is not similar to that of the above composition, it will be difficult to form a homogeneous mixture.
Even when heated and foamed, it was extremely difficult to obtain a uniformly foamed phenol-resin molded product.

In view of the above circumstances, the inventors of the present invention have determined that when obtaining a phenol-resin molded article, a bone material that is not reactive with the foamable resin composition to be coated, regardless of its shape, size, and bulk specific gravity, has been developed. A uniform phenol-resin foam molded product can be easily obtained by coating material particles with the composition in advance, filling the room with the foamable resin-coated particles, and heating, etc. We discovered the facts and arrived at this invention.

Thus, the gist of the present invention is that aggregate particles are coated with a foamable resin composition containing as essential components a Novo2-type pheno-μ resin initial combination, a decomposable blowing agent, and a curing agent. *Consists in fine expandable resin-coated particles.

The above-mentioned foamable resin-coated particles are heated to form a heat-insulating granular material containing aggregate on the inside and covered with a foamed phenol resin layer on the outside. For example, if the particles of the present invention are filled into a mold or the like and heated, a pheno-μ molded body in which aggregate particles are evenly distributed throughout the pheno-foam can be obtained.

The novolac-type pheno-resin initial composite, which is the main raw material of this invention, is a so-called novolac resin known in the art, which is obtained by reacting pheno-/L/s and aldehydes in the presence of an acidic catalyst. It is called a type pheno-y resin and means a resin that can undergo further polymerization in the presence of a curing agent. In addition to pheno-μ, phenols include 3,5-xyleno-7p, m-cresol, 2,5-xyleno-μ, 3,
Includes 4-xyleno-μ, 2,4-xyleno-μ, 0-Frezy"s I'-Frezee μ, etc. Also included are aldehydes and companies, forma μdehyde, paraforma μdehyde,
Hexamethylenetetramine, Fufurer p1 Acedoμ
Includes dehydes, acetals, etc.

These resins are generally in powder form at room temperature.

A preferred precondensate for use in this invention is a condensate of pheno-μ and formamide μdehyde.

In this invention, the decomposable blowing agent refers to inorganic and organic blowing agents that can decompose and generate gas during heating and curing in a composition obtained by mixing a novolak type pheno-y resin initial composite and a curing agent. . Typical examples of these are N, N/
- organically decomposable blowing agents such as dinitrosopentamethylenetetramine, benzenesulfonylhydrazide, azobisisobutyronitrile, azocafflevonamide, balatoluence μhonylhydrazide, and sodium deuterate;
Examples include inorganic decomposition type blowing agents such as alkaline acid, ammonium bicarbonate, ammonium nitrite, and azide compounds (eg, caN, ). All of these are in powder form.

The curing agent used in this invention means a compound that can be decomposed by heating and can undergo a crosslinking reaction with the initial shrinkage product of the novolac phenol μ resin. Examples of such compounds include compounds that are used to form phenolic resins by reaction with phenol-μ compounds, and are usually in the form of powder, similar to the phenol IV dehyde. Specific examples include hexamethylenetetramine, paraforma μdehyde, methyl, dioxolane, F lioxane, tetraogysan, trimethylonoriphosphine, S
−) Examples include riazine.

The amount of the blowing agent to be added is determined mainly by taking into account the desired density of the final foam, but a suitable amount is 1 to 50 parts by weight per 100 parts by weight of the novolac phenol A' resin. , 4 to 8 parts by weight are preferred.

The amount of curing agent added is generally 1 to 30 parts by weight per 100 parts by weight of novolak type pheno resin.
~15 parts by weight is preferred.

The foamable resin composition of the present invention may also contain small amounts of other various additives, such as fillers such as clay. The amount of these additives is preferably 100 parts by weight or less based on 100 parts by weight of the novolac type pheno-μ resin.

The foamable resin composition of the present invention is usually prepared by heating the composition of the novolak type pheno-μ resin initial composite, decomposed foaming agent, and curing agent (and other additives) by heating
/ etc. to mix uniformly and crush it to an outer diameter of 111 mm.
Used in powder form below 11. Of course, you can use granulated ones.

The aggregate may include grains, organic or nonnuclear particles, or mixtures thereof, but those that do not react with the foamable resin composition are preferred.

Examples of inorganic substances include pearlite, shirasupa μm,
Glass Parun, Glass 'Jh Foam Grain s tJ Lye Cotton Granules, Rock Wool Granules, Slap, Clay Foam Granules 9
．． Examples include sand, stone granules, and metallic granules.

Examples of organic materials include synthetic resin particles and foamed particles thereof, wood powder particles, abrasive grains, etc., but resins having heat resistance of 100°C or higher are usually preferred, such as resol type phenol μ resin foam particles, styrene-anhydrous. Examples include foamed maleic acid copolymer resin beads and foamed polypropylene beads.

There is no particular limitation on the shape of the aggregate particles, and they may be spherical, crushed fragments, or irregularly shaped.

The particle size ranges from microscopic particles with a particle size of 1g to particle sizes of 40-50M.
Any size up to large grains of J may be used. Also, the density of aggregate particles is
There is no particular limitation, and when considering the use of a lightweight foam molded product, it is sufficient to select an aggregate with a density of not more than xf/ai, and a high-density aggregate may also be used.

The method of coating the aggregate particles with the foamable resin composition includes a temperature range that allows the foamable resin composition in powder form to melt and adhere;
In other words, from the softening point of about 80℃, it foams and hardens at about 1
heating the aggregate particles to a temperature ranging from 10 to 120°C;
In this state, the foamable resin composition (powder) is contacted by spraying, sprinkling, etc. to obtain coated particles, or conversely, the foamable composition is completely heated and softened to coat the aggregate particles. be.

Another method is to use a binder. Typical binders include water, methyl alcohol, toluene, and the like. Among these, water is most preferred. When such a binder is used, the aggregate particles and the powdered foamable resin composition may be rolled together, for example, in a bakery granulator while blowing the binder. When these binders are used, it is preferable to remove the binders through a drying process after coating and granulation. This is because if water remains, for example, it may have an adverse effect on the foaming ratio and bubbles.

Further, any binder may be used as long as it does not have an adverse effect on foaming. For example, other binders that may be used include a 3-596 aqueous solution of sticky polyvinyl A/:=+-A/, silicone oil, animal and vegetable oils, and the like. When these binders are used, they remain in the coated particles of the present invention, and such coated particles are also included in the present invention.

The amount of coating of the foamable resin composition on the aggregate particles varies depending on the foamability of the composition, the type and shape of the aggregate, etc., but it is usually more than the weight of 1 liter of aggregate particles per lv volume. A good coating amount is 15 to 500 tons.

The more uniformly the composition is coated on the aggregate particles, the better; however, if a molded article is to be obtained, a spotty coating is acceptable.

In addition, the coating resin composition of the obtained expandable resin-coated particles of the present invention may be a composition having secondary foamability, which is partially foamed and cured.

Such expandable resin-coated particles can be formed into a foam molded article of any shape. For example, a foamable resin composition is applied to a room having a desired shape with a force of usually 20 to 100% by volume.
When filled and heated to a predetermined temperature (for example, about 150 to 180°C), each particle of d% damage expands and is fused to form an integrally formed foamed product.

The foamed molded product obtained here is different from one obtained by simply mixing and foaming a foamable resin composition and aggregate particles, in that the aggregate is substantially uniformly dispersed in the foam. Here, a molded product in which aggregate particles are substantially uniformly dispersed means that aggregate particles are not present only in the surface layer or center of the molded product. Therefore, a molded body in which the aggregate particles are substantially uniformly dispersed is obtained, so that such a molded body has various quality characteristics such as high dimensional stability and uniform heat insulation effect. In addition, during foam molding, it has been recognized that aggregate is substantially uniformly dispersed in the foam molded product even at a low filling rate of 2096 of Casa Shunju. This is one of the nine new and surprising findings we discovered.

Thus, according to one aspect of the present invention, aggregate particles as a foam material are coated with a foamable resin composition containing as essential components a novolac phenol-resin precondensate, a decomposable blowing agent, and a curing agent. Provided is a foam molded article of a novolac-cross-phenol μ resin containing aggregate particles, characterized in that the aggregate particles are substantially uniformly dispersed.

The shape of the molded product of this invention is not particularly limited, but may be plate-shaped,
It may be cylindrical or the like. For example, if it is plate-shaped, it can be used as a heat insulating board for buildings, and if it is cylindrical, it can be used as a heat-insulating material to cover pipes. Furthermore, this molded product is extremely lightweight and has excellent adhesiveness to other objects (such as iron plates), so it is suitable as a composite molded product such as a sizing board. However, this does not limit the scope of the invention.

Example 1゜Novo2Tsuku Lid Noroho μA Dehyde Resin Powder 1
To 00 parts by weight, 5 parts by weight of dinitronobentamethylenetetramine as a blowing agent and 10 parts by weight of xamethylenetetramine as a curing agent were added and kneaded using a heating roller. Thereafter, it was pulverized to obtain a powdered resin composition. This foamable resin composition was a powder with a 100 mesh size of 0.596 mm, a melting point of 81° C., and a melting time of 76 seconds at 150° C.

Next, reso type IV phenol μm with an average particle size of 5.0 sieve
The above resin composition powder was granulated for 3 minutes using a Pan-Cun granulator using the spherical foamed foam of the VmAdehyde resin as an aggregate. In addition, water was used as a binder at that time, and the nozzle erupted in a shivering pattern. The ratio of raw materials during granulation is 20,000 yen (bulk) for aggregate and 300 yen for bonding rigidity. This is Novo 2 Tsukuya Fukou Nol Resin Composition Powder '15 QQ (bulk).

Next, the coated grains obtained in this step were air-dried day and night.
The resulting coated particles were dried for 6 hours in a hot air circulating constant temperature bath at 90°C. It did not peel off even if handled roughly. Note that this coating was not yet completely foamed and had an average thickness of OJ'1 wg.

Next, the coated particles were placed on top of the powder and foamed and hardened for 30 minutes in a hot air circulation constant temperature bath at 160°C.

The obtained foam is yellowish, has a particle size of 10-14U, and is spherical with a skin on the surface.Resol-type phenolic resin foam particles exist inside (aggregate), and dense air bubbles exist on the outside. It was a composite foam ball in which a foam layer of the structure had a novolac type phenol tv@J resin.

Next, the coated composite foam sphere was placed in a metal mold (220X
#1 is full (1
0096), the lid was closed, and the mixture was kept in a hot air circulation constant temperature bath at 160° C. for 1 hour. Thereafter, the overflow was taken out from the constant temperature bath and taken out from the foamed molded product t-m.

This obtained foamed molded product has a surface made of Novo 2 Tsuku Fue,
The no-μ resin foam layer further foams, and the novolak-type pheno resin foam layer with a yellowish, dense cell structure fills all the voids between the filled particles, completely bonding between the particles, and forming an aggregate. (Reso/I/Wi pheno-μ resin foam particles) was a composite foamed molded article of novodiscitric acid pheno-V resin in which the foamed particles of pheno-μ resin were uniformly dispersed.

Incidentally, the density Jd of this molded body is 350 K@/ns
"Met.

In addition, 5096 pieces of the above composite foam 11 were filled into a metal *m in bulk and heated and molded, and the aggregate was uniformly dispersed in the molded body, and the foam was formed at a high magnification. It is a composite foam molded product filled with a novolac-type phenol/1/resin foam layer with a yellowish and dense cell structure, and the density is 100 Kfl/ti? Met.

Examples 2.3 and 4° Other examples f coated using water as binder: Example 1
t- is shown in Table 1. Note that the ratio of raw materials during coating is the same as in Example 1.

(Continued in the margin below) Example 6 Powder of a foamable resin composition Prepared in the same manner as in Example 1.

Then, the average particle size 3−'? Using 1 ml of foamed glass (trade name: Cellobeads, manufactured by Toyota Boseki Co., Ltd.) as an aggregate, the resin composition powder was coated with a pan-shaped granulator. In addition, as a binder at that time, expanded methyl p-alco-fi/(reagent special grade) and F-lichlorotri7-oloethane were used in a volume ratio of 1
For pair 5, the mixture was used and sprayed into a mist using a nozzle. In addition, the raw material ratio at the time of coating is aggregate 2000.
Rigid connection to Q (bulk) 300. Novolak type pheno-V resin composition powder 75 QQ (bulk).

Next, the coated particles obtained in this step were air-dried for a day and night, and
It was dried for 72 hours in a hot air circulation constant temperature bath at ℃.

The obtained coated particles are those in which the foamable resin mixture powder is dissolved and fused to the surface of the aggregate (foamed glass particles) to form a thin film, and the powder is completely dissolved. No, it solidifies. Moreover, this coating did not peel off even when handled roughly. The coating had an average thickness of 0.15 m.

Next, the coated particles were placed on the powder and foamed and cured for 30 minutes in a hot air circulation constant temperature bath at 160°C. This was a spherical novolak pheno-μ resin composite foaming method that had a skin and was covered with a foam layer with a dense cell structure in which foamed glass particles existed inside.

Examples 6, 7 and 8 Other examples, including Example 5, are shown in Table 2, including Example 5, in which granulation was performed using methyμ alpha and trichlorotrifluoroethane (Fl13) as binders. Note that the ratio of raw materials during coating is the same in all cases.

(Margin below, continued on next page) ■ ■ ,1 罎 Training Example 9゜ The powder of the foamable resin composition was prepared in the same manner as in Example 1.

Next, average particle size 3. The resin composition powder was coated using the foamed glass of (2) as an aggregate using a pan-shaped granulator.

In addition, the binder at that time has a molecular weight of 190 to 210.
O polyethylene glyco-μtv! It was used and sprayed from a nozzle. In addition, the raw material ratio at the time of coating is 2oo of mori and 2oo of aggregate.
oc (bulk), binder 500. This is Novo 2 Tsukuya Fukou Nol Resin Composition Powder SO CC (bulk).

Next, the coated particles obtained in this step were allowed to stand overnight.

The obtained coated particles are in a state in which the foamable resin mixture powder is attached to the surface of the aggregate (foamed glass particles) due to the presence of a binder), and will not peel off even if handled roughly. There wasn't.

The average thickness of this coated wire is 0.22 wm.

Next, it was placed on the coated grain powder and was foamed and hardened for 30 minutes in a hot air circulation constant temperature bath at 160°C.

The obtained foam is a spherical pheno-μ resin composite manufactured by Novo2Tsuku, which has a brownish color and a particle size of 6 to 9, contains a skin, has foamed glass particles inside, and is covered with a surface layer of a foamed layer. It was a foaming method.

Example 10 A powder of a 0° foamable resin composition was prepared in the same manner as in Example 1.

Next, foamed glass with an average particle size of 3.7IllJI+ was
Heat for 2 hours in a hot air circulation thermostat at 0°C, quickly remove from the tank, and place in an atmosphere at 60°C in advance w4!1
The powder was poured into the resin composition powder heated in a pan-shaped granulator, and coated.

In addition, as for the raw material ratio at the time of coating, foamed 4 as aggregate
The novolac resin composition powder ryacc (bulk) is 27 grains 2oo cc (bulk).

The obtained coated particles were formed by softening and melting the foamable resin composition powder and adhering to the surface of the aggregate (foamed glass), and formed a uniform thin film. Note that this coating did not release #I even when handled roughly.

Also, this subject had an average thickness of 0.15 fins.

Next, the expandable coated particles were placed on the abrasive powder for 16 minutes.
It was foamed and cured for 30 minutes in a hot air circulation constant temperature bath at 0°C.

The obtained foam is yellowish, has a particle size of 8 to 10 particles, contains a skin, and is a novolak phenol μ resin composite foam ball covered with a foam layer with a dense cell structure in which foamed glass particles exist inside. Met.

Claims (1)

[Claims] 1. The aggregate particles are coated with a foamable resin composition containing a novolak type pheno-y resin initial condensate, a decomposed foaming agent, and a curing agent as essential components. expandable resin-coated particles. 2. The particles according to claim 1, wherein the aggregate particles are organic or inorganic particles or a mixture thereof. 3. The particles according to claim 2, wherein the organic particles are foamed beads of resol ivg phenol μ resin or foamed beads of styrene-maleic anhydride copolymer resin. 4. The particles according to claim 2, wherein the inorganic particles are perlite, shirasu balloons, glass balloons, glass foam particles, glass cotton granules, rockwoo μ particles, or crushed products thereof. 5. The particles according to claim 1, wherein the foamable resin composition is in the form of a powder, and its size is smaller than that of the aggregate particles. 6. Claim 1, wherein the amount of foamable resin composition used per 1 liter of aggregate particles A/II is at least 5 t.
Particles described in section.