CN101659772B

CN101659772B - Expandable particles of reclaimed styrene resin, expanded beads, and molded foam

Info

Publication number: CN101659772B
Application number: CN2009100097631A
Authority: CN
Inventors: 中岫弘; 齐藤诚; 田中龙介; 国见诚; 加藤哲也
Original assignee: JSP Corp
Current assignee: JSP Corp
Priority date: 2001-09-12
Filing date: 2002-09-09
Publication date: 2011-11-09
Anticipated expiration: 2022-09-09
Also published as: CN1931914A; CN101659772A; CN100460462C

Abstract

The invention provides expandable reclaimed-styrene resin particles, expandable reclaimed-styrene beads expanded by the expandable reclaimed-styrene resin particles, and expandable reclaimed-styrene molding products obtained by molding expandable reclaimed-styrene beads. The expandable reclaimed-styrene resin particles contains nuclei formed by expandable reclaimed-styrene resin, and novel styrene resin packaging the nuclei inside, it is divided into five equal parts from the surface toward the center of the particle, and the weight average molecular weight of the surface part formed from the surface to the 1/5 position is 50 thousand or more than that of the center part at the 1/5 position from the center to the surface. The invention solves the problem of the prior expandable reclaimed-styrene resin particles, provides expandable reclaimed-styrene resin particles and expandable reclaimed-styrene molding products with excellent appearance, fusing and/or mechanical intensity.

Description

Reclaimed expandable styrene resin particles, foamed beads and molded foam

The present patent application is patent application: 200610137535.9 divide an application, this patent application is patent application: the dividing an application of 02817795.9 (international application no is PCT/JP02/09147), more than Shen Qing the applying date is on September 9th, 2002, and invention and created name is: reclaimed expandable styrene resin particles, foamed beads and molded foam.

Technical field

The invention relates to the reclaimed expandable styrene resin particles, be molded foam by polystyrene frothing mold product regenerated reclaimed expandable styrene resin particles and manufacture method thereof and regenerated phenylethene that this particle frothing mold is obtained.

Background technology

In the past, the polystyrene molded foam was after using once, perhaps by burning disposal, perhaps being heated contraction formation polystyrene is reclaimed and is reused, but reusable ratio is not high, thereby improving utilization ratio again and being will need the social problem that solves from now on.

The polystyrene molded foam is made technology that contraction block reclaimed have been developed and has finished, 1999, have about 33% to be that form with thermal contraction piece etc. is reclaimed in the polystyrene molded foam circulation in Japan, be mainly used in the daily necessities that adopt injection molding, and the purposes such as material of construction that adopt extrusion molding.At present, the polystyrene molded foam utilize method limited again, press for and enlarge its purposes.

On the other hand, define according to regenerated, with the based resin foamed molding of expandable styrene, the final phenylethylene resin series after making the polystyrene molded foam and using, preferably being used as expandable styrene again is resin, rather than is used for other purposes as polystyrene.But to make expandable styrene through industry regeneration be that the example of resin is still rare to the phenylethylene resin series that will be reclaimed by the polystyrene molded foam at present.

Become the method that expandable styrene is a resin as regeneration such as constrictor by the polystyrene molded foam, with forcing machine above-mentioned constrictor is made pellet, make the method for its dipping whipping agent be considered to realize than being easier to technically, but in this method, productivity depends on the size of particles of pellet.Be the particle of the bigger particle diameter 0.3～1.5mm of resin demand particularly, cause the spray volume in extruding operation low, and significantly reduce that economy is also bad owing to the dust of sneaking into causes productivity as expandable styrene.

As the method that addresses these problems, open in the flat 6-87973 communique the spy and to have proposed a kind of method, the constrictor of polystyrene molded foam there are not stretching fusion and pulverizing, resulting styrene resin particles is scattered in the aqueous medium that contains the organic system dispersion agent, make it to soak into the easy volatile whipping agent, make the reclaimed expandable styrene resin particles.Adopt this method, can allow to sneak into dust to a certain degree, in the steeping process of whipping agent, also have higher productivity.But, the reclaimed expandable styrene resin particles that obtains in this way, compare with new expandable styrene resin beads, outward appearance when making moulded parts and intensity are all poor, therefore its moulded parts that is suitable for is only limited to the goods not too high to requirement of strength, perhaps must adopt, but this method must be used for and the new mixing machinery of freshly prepd expandable styrene resin beads blended with arbitrary proportion and freshly prepd expandable styrene resin beads blended method.

The objective of the invention is, solve the problem of reclaimed expandable styrene resin particles in the past, it is molded foam that the reclaimed expandable styrene resin particles and the regenerated phenylethene of outward appearance, fusion and/or the physical strength excellence of moulded parts are provided.

Summary of the invention

According to a kind of mode of the present invention, the manufacture method of reclaimed expandable styrene resin particles is provided, promptly, with the regenerated phenylethene resin beads as nuclear, it is suspended in the aqueous medium, in this suspension, adds polymerization starter, make it to soak into the regenerated phenylethene resin beads, then add styrenic monomers and carry out polymerization, flood whipping agent then.

According to another way of the present invention, provide the reclaimed expandable that obtains with above-mentioned manufacture method styrene resin particles.

According to another mode of the present invention, the reclaimed expandable styrene resin particles is provided, it contains by regenerated phenylethene is the nuclear of resin formation and the fresh phenylethylene resin series of interior this nuclear of bag, regenerated phenylethene is that the weight-average molecular weight of resin is 100,000～250,000, and the weight-average molecular weight of skin section is that resin is high more than 50,000 than regenerated phenylethene.

Mode according to another preferred, the reclaimed expandable styrene resin particles is provided, it contains by regenerated phenylethene is the nuclear of resin formation and the fresh phenylethylene resin series of interior this nuclear of bag, be divided into 5 timesharing such as grade from the surface of particle to the center of particle, the weight-average molecular weight of the surface portion that is formed to 1/5 place by the surface is than more than the weight-average molecular weight high 50,000 or 50,000 that is reached the centre portions that 1/5 place forms by mind-set surface in above-mentioned.

According to another mode of the present invention, it is foamed beads that the regenerated phenylethene that above-mentioned reclaimed expandable styrene resin particles foaming is obtained is provided.

Mode according to another preferred, providing above-mentioned regenerated phenylethene is that the regenerated phenylethene that the foamed beads molding obtains is a molded foam.

According to another mode of the present invention, provide the nuclear that uses in the above-mentioned reclaimed expandable styrene resin particles manufacture method.

Description of drawings

Fig. 1 is the diagram that is used to illustrate skin section of the present invention and molecular weight determination thereof.

Fig. 2 is the diagram that is used to illustrate surface portion of the present invention and centre portions and their molecular weight determination.

Fig. 3 is the GPC spectrogram of embodiment 15 and embodiment 16.

Embodiment

Describe reclaimed expandable styrene resin particles of the present invention below in detail and be molded foam the regenerated phenylethene that its frothing mold obtains.

The manufacture method of reclaimed expandable phenylethylene resin series of the present invention at first is described.

In manufacture method of the present invention, use small-particle by exhausted foamed styrene regenerated phenylethylene resin series as nuclear.

Be used as the regenerated phenylethene resin beads of nuclear, can use the exhausted foamed styrene is resin heating and/or the crushed material that subtracts the regenerating resin of appearance.The constrictor of phenylethylene resin series or melts can prepare by the following stated, promptly, to as required used phenylethylene resin series meal be broken into suitable size, contraction or fusion that the bubble destruction that utilize heat shrink then, is caused by compression is shunk, caused by frictional heat prepare.Used foamed styrene is a resin, not only comprises with expandable styrene being the moulded parts of resin die molding, also comprises the goods of foamable.

In addition, can also use pellet that this crushed material extrusion molding is made or crushed material that this pellet is further pulverized as nuclear.Can adjust proportion by extrusion molding, can also utilize the screen cloth that in forcing machine, is provided with to remove foreign matter.

In addition, can contain little powdered inorganics and/or organic system lubricant in the regenerated phenylethene resin beads, they can play the effect of bladder regulator.

As little powdered inorganics, preferably select talcum or lime carbonate for use.Here said talcum is meant that with silicon oxide and magnesium oxide be main component and the mixture that contains micro-aluminum oxide, ferric oxide etc.In addition, the median size of little powdered inorganics is advisable at 100 μ m or below the 100 μ m, preferably 30 μ m or below the 30 μ m.When the median size of little powdered inorganics surpassed 100 μ m, the effect that reduces the bubble size of resin particle tended to reduce.

With respect to the regenerated phenylethene resin beads, the use level of little powdered inorganics is advisable in the scope of 0.1～5% (weight), preferably the scope of 0.5～2% (weight).When the use level of micro mist shape inorganics is lower than 0.1% (weight), often can not fully obtain to reduce the effect of bubble size; Otherwise when surpassing 5% (weight), bubble size is very little, resin fusing during molding, and the outward appearance of moulded parts usually can worsen.

As the organic system lubricant, preferably use the metal-salt of senior lipid acid such as senior lipid acid bisamide such as methylene-bis stearylamide, ethylenebisstearamide, ethylenebisoleoamide, Zinic stearas, Magnesium Stearate, zinc oleate.

With respect to the regenerated phenylethene resin beads, the use level of organic system lubricant is advisable in the scope of 0.01～0.2% (weight), preferably the scope of 0.02～0.1% (weight).When the use level of organic system lubricant was lower than 0.01% (weight), the effect that reduces bubble size tended to reduce; Otherwise when surpassing 0.2% (weight), bubble size is very little, resin fusing during molding, and the outward appearance of moulded parts usually worsens.

Specifically, can little powdered inorganics and/or organic system lubricant is mixing when extrusion molding, in this occasion, in advance crushed material and bladder regulator are mixed, then extrusion molding.Crushed material can adopt known in the past method to carry out with mixing of bladder regulator, for example can use ribbon blender, V-type mixing machine, enjoyed the She Er mixing machine, mixing machine such as レデイゲ-mixing machine.

Preferably will carry out painted used polystyrene molded foam with dyestuff etc. in advance and remove, and then make constrictor or the melts that used foamed styrene is a resin.If sneak into painted moulded parts, reclaimed expandable styrene resin particles then therefrom and molded foam will be colored, and the use value of product suffers damage, thereby inadvisable.

Be purpose and the constrictor or the melts of phenylethylene resin series carried out heat fusing preferably to adjust proportion.In this operation, be that the proportion of resin is adjusted into more than 0.6 or 0.6 and is advisable with regenerated phenylethene, preferably be adjusted into more than 0.9 or 0.9.Proportion is lower than at 0.6 o'clock, because the dispersion instability of resin particle, thereby in polymerization process, producing excessive particle, yield rate is often lower.The heat fusing of styrene resin can use forcing machine, heating drum etc. in the past known method carry out.

This heat fusing should not have cooling curing under the less state of residual strain or strain in resulting resin, this point is very important.If residual in the resin particle have a strain, strain reduces in the operation of polymerization process and dipping whipping agent, shrinks on draw direction, and resulting reclaimed expandable styrene resin particles might not be spherical and become flats.Therefore, preferably there is not the stretching fusion with forcing machine.If under stretched state, carry out heat fusing, in the stretching resin that obtains behind the cooling curing strain will residually be arranged.

But, even in the heat fusing operation residual strain in the resin, as long as under the temperature more than the softening temperature of resin the health certain hour, strain is reduced.

Be used to pulverize the pulverizer of regenerating resin, the pulverizer that can use plastics to use as long as this pulverizer can be ground into polystyrene the scope of target value 0.3～3mm, has no particular limits.

The regenerated phenylethene of size is a resin beyond the target value that obtains through pulverizing, through supplying with the fusion operation of using forcing machine etc. after the screening once more.

By the nuclear that the regenerated phenylethene resin beads constitutes, its mean diameter is advisable at 0.2mm or more than the 0.2mm, 0.4mm or more than the 0.4mm preferably, preferably 0.5mm or more than the 0.5mm.In addition, this median size is advisable at 3mm or below the 3mm, 2mm or below the 2mm preferably, preferably 1.7mm or below the 1.7mm.

When the size of regenerated phenylethene resin beads surpassed 3mm, shape of products often was difficult to form spherical, when being lower than 0.2mm, carry out polymerization after particle diameter still too small, the demand when making the reclaimed expandable styrene resin particles is less.

In addition, in the regenerated phenylethene resin beads that forms nuclear, the following particle content of 300 μ m or 300 μ m should be lower than 1% (weight).The content of 300 μ m or the following particle of 300 μ m is when 1% (weight) is above, and the outward appearance when forming moulded parts might worsen.

The weight-average molecular weight of regenerated phenylethene resin beads that forms nuclear is more than 100,000 or 100,000, be advisable below 250,000 or 250,000.The weight-average molecular weight of regenerated phenylethene resin beads is lower than at 100,000 o'clock, often can not obtain enough intensity, surpasses at 250,000 o'clock, and particle often is difficult to form spherical, preferably more than 150,000, below 230,000.

The ratio that forms the regenerated phenylethene resin beads of nuclear is that 30% (weight) or 30% (weight) are above, 70% (weight) or below 70% (weight), preferably above, 50% (weight) of 30% (weight) or 30% (weight) or below 50% (weight).When the ratio of regenerated phenylethene resin beads was lower than 30% (weight), particle united two into one easily each other in polymerization process, when surpassing 70% (weight), can not obtain enough intensity sometimes.

In the manufacture method of reclaimed expandable phenylethylene resin series of the present invention, at first, as nuclear, it is suspended in the aqueous medium with the regenerated phenylethene resin beads.Dispersion in aqueous medium typically uses the device that has agitating vane to be carried out, for the dispersive condition without limits.In addition, preferably disperse with dispersion agent.

The dispersion agent that uses among the present invention, so long as the dispersion agent that uses during suspension polymerization gets final product, have no particular limits, for example can enumerate organic system dispersion agents such as polyvinyl alcohol, polyvinylpyrrolidone, methylcellulose gum, insoluble inorganic salt such as trimagnesium phosphate, tricalcium phosphate.Can use tensio-active agent in addition, described tensio-active agent can use sodium oleate, Sodium dodecylbenzene sulfonate, in suspension polymerization in normally used other anion surfactant, the nonionogenic tenside any.In these dispersion agents, consider from the stability of the oil droplet of styrenic monomers, preferentially select the organic system dispersion agent for use.

Subsequently, in above-mentioned suspension, add the styrenic monomers of having dissolved polymerization starter in advance, make it to soak into the regenerated phenylethene resin beads that forms nuclear, then add styrenic monomers and carry out polymerization.

The styrenic monomers of using among the present invention be in the styrene derivativess such as vinylbenzene and alpha-methyl styrene, Vinyl toluene more than a kind or a kind, perhaps more than 2 kinds or 2 kinds, perhaps other the combination etc. of polymerisable monomer of ethene nitrile, vinylchlorid etc. such as methacrylic ester, corresponding acrylate, vinyl cyanide, methacrylonitrile such as they and methyl methacrylate, Jia Jibingxisuanyizhi.In addition, can also use linking agents such as Vinylstyrene, diallyl phthalate.

Also polymerization starter can be dissolved in back interpolation in the solvent, make it to soak into the regenerated phenylethene resin beads that forms nuclear.Described solvent can use aliphatic hydrocarbons such as aromatic hydrocarbonss such as ethylbenzene, toluene, heptane, octane etc., is using the occasion of solvent, with respect to its consumption of styrenic monomers usually in 3% (weight) or below 3% (weight).

The polymerization starter that uses in the polyreaction is so long as getting final product of using in the suspension polymerization, have no particular limits, for example can use in the azo-compounds such as organo-peroxide, Diisopropyl azodicarboxylate such as benzoyl peroxide, tert-butyl hydroperoxide-2-ethylhexyl carbonic ether, t-butyl per(oxy)benzoate more than a kind or a kind, perhaps more than 2 kinds or 2 kinds.

The consumption of polymerization starter is advisable in the scope of 0.1～0.5% (weight) with respect to monomer in general according to the kind of polymerization starter and different.In addition, polymerization starter can be dissolved in styrenic monomers or the solvent and add.Described solvent can use aliphatic hydrocarbons such as aromatic hydrocarbonss such as ethylbenzene, toluene, heptane, octane etc., is using the occasion of these solvents, with respect to its consumption of styrenic monomers usually in 3% (weight) or below 3% (weight).

Have as the method that makes the nuclear that constitutes by the regenerated phenylethene resin beads that is scattered in the aqueous medium soak into styrenic monomers, add the method for styrenic monomers separately, and in aqueous medium, add the method for adding behind the fine dispersive dispersion liquids of formation such as styrene monomer and dispersion agent.In addition, also these methods can be used in combination.

Styrenic monomers and dispersion agent etc. added to making its fine dispersive method in the aqueous medium, use the device that has agitating vane to carry out usually.Its condition but is preferably used homomixer as dispersive method more imperceptibly without limits.At this moment, the droplet diameter of styrenic monomers dispersive dispersion liquid is advisable with the degree that is distributed to the particle diameter that is less than or equal to nuclear.If under the big state of the particle diameter of droplet diameter ratio nuclear, add in the aqueous medium, then in the oil droplet of styrenic monomers dispersive dispersion liquid, will enter a plurality of resin particles, resin particle adheres to, plasticising or combine together, and generates excessive particle easily.

The interpolation of styrenic monomers can be carried out also can carrying out continuously in batches.The speed of adding is different according to capacity, shape and the polymerization temperature etc. of poly-unit, can suitably select.Polymerization temperature is advisable at 60～105 ℃.

In addition, in the present invention, also can be dissolved in styrenic monomers or the above-mentioned solvent and use with lipid acid bisamides such as lipid acid monoamide such as oleylamide, stearylamide, methylene-bis stearylamide, ethylenebisstearamides as bladder regulator.

Whipping agent is in polymerization process or polymerization is pressed in the container afterwards, is warming up to the above temperature of softening temperature of common regenerated phenylethene resin beads, and whipping agent is infiltrated up in the resin particle.Described whipping agent does not preferably dissolve resin particle or only makes the whipping agent of its slight swelling, specifically can use aliphatic hydrocarbons such as propane, normal butane, Trimethylmethane, Skellysolve A, iso-pentane, normal hexane, ester ring type hydrocarbon such as hexanaphthene, pentamethylene.With respect to the regenerated phenylethene resin beads, the consumption of these whipping agents is 3～15% (weight) normally.

When the dipping whipping agent, can also flood fire retardant in order to improve flame retardant resistance.

The bromide that described fire retardant preferably mixes with polystyrene.Preferentially select tetrabromoethane, hexabromocyclododecane, 2 for use as bromide, two (4-allyloxy-3, the 5-dibromo) propane of 2-, hexabromobenzene etc.In addition, can also and use with superoxide such as dicumyl peroxide.With respect to the regenerated phenylethene resin beads, their consumption is advisable in 0.5～5% (weight), preferably 1.5～3.5% (weight).When being lower than 0.5% (weight), flame retardant resistance is low, and when surpassing 5% (weight), mouldability is deterioration often.

Preferably being scattered in it in aqueous solution that contains tensio-active agent equably with whipping appts after, adds again fire retardant.Directly add if fire retardant is not made the aqueous solution, the dispersion of fire retardant is insufficient, and the absorption in the regenerated phenylethene resin beads can reduce.Particularly for the fire retardant of powder, this tendency is more remarkable.

The reclaimed expandable styrene resin particles after finishing at dipping whipping agent (and fire retardant), discharging and dehydrate in by paradigmatic system, can be covered surface-coated dose as required.Such coating agent can use employed coating agent in the known in the past expandable styrene resin beads, for example Zinic stearas, glycerol stearate, stearic acid monoglyceryl ester, castor-oil plant winterized stearin, tallow winterized stearin, type siloxane, antistatic agent etc.

Total molecular weight can be by adjusting polymerization starter concentration or and with chain-transfer agent or use these two kinds of methods to adjust simultaneously.Described chain-transfer agent can use known in the past chain-transfer agents such as n-octyl mercaptan, lauryl mercaptan, α-Jia Jibenyixierjuwu.Usually, when the concentration of polymerization starter reduced, total molecular weight increased.

Therefore, by adjusting the concentration of polymerization starter, the weight-average molecular weight that can obtain the reclaimed expandable styrene resin particles is a reclaimed expandable styrene resin particles more than 150% or 150%, below 300% or 300% with respect to the weight-average molecular weight of the regenerated phenylethene resin beads that becomes nuclear.

In addition, by reducing oxygen concn, can improve the weight-average molecular weight of the near surface part of reclaimed expandable styrene resin particles.

Specifically,, remain on 7% (volume) or below 7% (volume), can adjust the polymerization molecular-weight average 20% or 20% when following at the containing ratio of styrenic monomers by making the oxygen concn in the reactive tank.Preferably, one side remains on 5% (volume) with oxygen concn or below 5% (volume), preferably remains on 1% (volume) or below 1% (volume), simultaneously add styrenic monomers.Described " containing ratio of styrenic monomers is below 20% or 20% " be meant, the containing ratio when being located at the whole polymerization of the styrenic monomers of adding in the reactive system is 0% o'clock, when polymerization containing ratio latter half reaches below 20% or 20%.

The containing ratio of styrenic monomers is 20% or 20% when following, by the oxygen concn in the reactive tank being remained on 7% (volume) or below 7% (volume), the lower molecular weightization that can suppress the resin particle surface portion is adjusted into the weight-average molecular weight of surface portion than more than centre portions high 50,000 or 50,000.When oxygen concn surpassed 7% (volume), the polymer of surface portion quantized insufficient, and the outward appearance of the moulded parts of resulting reclaimed expandable phenylethylene resin series and intensity might reduce.

Preferably, begin to reach at 3% o'clock, by the oxygen concn in the reactive tank being remained on 1% (volume) or below 1% (volume), can further improving the weight-average molecular weight of surface portion to the containing ratio of styrenic monomers from polymerization.

Oxygen concn in the reactive tank can be by adjusting with the air in the inert gas replacement(metathesis)reaction grooves such as nitrogen.

Adopt this manufacture method, can obtain from the surface of particle to the center of particle be divided into 5 timesharing such as grade by the weight-average molecular weight of the surface portion on surface to 1/5 than the high reclaimed expandable styrene resin particles of weight-average molecular weight that reaches the centre portions that 1/5 place forms by mind-set surface in above-mentioned.From the molecular weight gradient of center to face, not to raise lentamente, but sharply raise near surface with certain ratio.

With reference to the accompanying drawings surface portion and centre portions are illustrated.As shown in Figure 1, the surface from resin particle 10 is divided into 5 five equilibriums to the center.From the part 1 that is positioned at the formation of outermost surface to 1/5 is surface portion.The weight-average molecular weight of surface portion is the weight-average molecular weight of this part 1.From the part 5 that is positioned at the most inboard center to 1/5 formation are centre portionss.The weight-average molecular weight of centre portions is the weight-average molecular weight that this part 5 is divided into the center of 5 timesharing such as grade.

In addition, begin to polymerization latter stage (for example the containing ratio of styrenic monomers reaches at 3% o'clock), if the oxygen concn in the reactive tank is remained on 1% (volume) or below 1% (volume), can further improve the molecular weight of surface portion from polymerization.Last in polyreaction is extremely near the part on surface, though the molecular weight of rising has the trend of reduction, if the oxygen concn in the reactive tank is remained on 1% (volume) or below 1% (volume), can suppress this reduction.

In general, when molecular weight belonged to lower molecular weight, foaminess and fusion character were often better, and when belonging to high molecular, often the strength ratio of outward appearance and moulded parts is better.That is, foaminess and fusion character and outward appearance and moulded parts intensity are reciprocal characteristics.In the reclaimed expandable styrene resin particles that obtains reducing oxygen concn, can make the molecular weight of centre portions keep lower molecular weight, make the molecular weight of surface portion keep high molecular simultaneously.Such particle can satisfy requirements such as foaminess, outward appearance and moulded parts intensity all sidedly.For example, in the foaminess that keeps to a certain degree, can obtain good surface appearance and higher moulded parts intensity.

In addition, the spectrogram that obtains of the employing gel permeation chromatography of the surface portion of this particle preferably has bimodal or acromion.Have bimodal or acromion means that molecular weight changes sharp.Acromion is formed by flex point.Have bimodal or acromion means that the distribution of molecular weight is not normal distribution, but lower molecular weight and high molecular omnipresence (uneven distribution).In the present invention, the spectrogram that obtains by gel permeation chromatography is to use two Hitachis to change into that post GL-R400M that industry (strain) society makes measures.Usually produce flex point at the two ends, bottom of spectrogram, but the acromion described in the present invention does not comprise these flex points (with reference to Fig. 3) yet.

As previously mentioned, in general, when molecular weight was lower molecular weight, foaminess and fusion character were often better, and when molecular weight was high molecular, outward appearance and moulded work intensity were often better.Molecular weight at surface portion is the high-molecular weight occasion, and outward appearance and moulded work intensity are good, but fusion character is tending towards reducing.By in surface portion, making lower molecular weight and high molecular omnipresence, can when keeping good appearance and high moulded work intensity, improve fusion character.

Particularly preferably be, the weight-average molecular weight of the surface portion of reclaimed expandable styrene resin particles is than more than centre portions high 50,000 or 50,000, below 100,000 or 100,000.The difference of above-mentioned weight-average molecular weight was less than 50,000 o'clock, and outward appearance and intensity can not fully improve sometimes.

Generative foaming moulded parts of the present invention is by making reclaimed expandable styrene resin particles frothing mold.

In general, utilize steam-heated cal(l)andria the pre-frothing of reclaimed expandable styrene resin particles to be reached the bulk density of regulation, to be filled into through the foamed beads of curing step in the molding die, with foamable moldings such as steams, make molded foam once more.

Moulded parts of the present invention has good surface appearance, fusion and/or intensity, can be used for food product containers, wrapping material and buffering material etc.

The following describes embodiments of the invention.

[manufacturing of reclaimed expandable styrene resin particles]

Embodiment 1

The preparation of＜the nuclear that constitutes by the regenerated phenylethene resin beads 〉

Making foamed styrene with 220 ℃ hot blasts is that resin molding (changing into the moulded work that Ha イ PVC-ズ SSB-HX makes that industry (strain) is made by Hitachi) shrinks, and obtains the constrictor of apparent specific gravity 0.75, size 500mm * 400mm * 100mm and heavy 15kg.Use is equipped with pulverizer (ZA-560 type pulverizer, the ホ of Co., Ltd.-ライ trade(brand)name) this constrictor of coarse reduction of the sieve of 10mm.The maximum length that the meal that obtain this moment minces is about 10mm, and volume weight is 0.5.

Then, use the 30mm forcing machine (T pattern head, sheet width 300mm, sheet thickness 1mm) that has venting hole, one side is with the speed drawing sheet material roughly the same with extruded velocity, and one side melt extrudes this meal and minces.

Then, before the cooling curing, with respect to extrude direction flatly with cylinder be provided with 1mm at interval, the slit of dark 0.5mm, cut off into about 10～15cm with stapling machine behind the cooling curing.Then, with the pulverizer (VM-16 type pulverizer, the オリエ of Co., Ltd. Application ト trade(brand)name) of the sieve that 2mm is installed that the cut off machine fine powder of resulting sheet phenylethylene resin series is broken.Use sieve that the classification of mincing of this fine powder is become the scope of 0.6～0.85mm, make the regenerated phenylethene resin beads.The weight-average molecular weight of this regenerated phenylethene resin beads is 17.2 ten thousand.

The preparation of＜reclaimed expandable styrene resin particles (reclaimed expandable particle) 〉

Pack in 5 liters withstand voltage stirred vessel deionized water 600g, above-mentioned regenerated phenylethene resin beads 700g, tricalcium phosphate 6.0g and Sodium dodecylbenzene sulfonate 0.06g, one side stirs one side and is warming up to 85 ℃.

Then, deionized water 1400g and polyvinyl alcohol 1.4g packed into mix in the monomer dispersion cup, again to wherein adding the styrene monomer 1300g that has dissolved benzoyl peroxide 3.7g and Benzoyl Peroxide tert-butyl ester 1.12g, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid was added in the container with the speed (adding speed 15g/ branch) that equates with 3 hours, be incubated 2 hours again.Be warming up to 100 ℃ then, divide 2 times, each 90g be pressed into butane (i/n than=4/6, weight ratio, below identical) as whipping agent.Be pressed into and be warming up to 115 ℃ after butane finishes, kept 10 hours, carry out the dipping of whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.The molecular-weight average of this polymer particle is 22.3 ten thousand.

Then, the sieve that uses mesh size 1.7mm is this polymer particle classification, with remaining in resin particle on the sieve as excessive particle, measures its weight.

Then,, add Zinic stearas 0.1% (weight), hardened castor oil 0.1% (weight) and carry out surface-coatedly, obtain the reclaimed expandable styrene resin particles remaining in resin particle on the sieve with the screen sizing of width of mesh 0.6mm.

To 50ml/g, slaking is after about 18 hours with the pre-frothing of resulting reclaimed expandable styrene resin particles, and to be resin mold molding machine VS-300 carry out molding with the molding pressure of 0.08Mpa to the foamed styrene that uses the industry of ダイセ Application to make, and obtains moulded parts.

Embodiment 2

The preparation of＜reclaimed expandable particle 〉

Pack in 5 liters withstand voltage stirred vessel regenerated phenylethene resin beads (weight-average molecular weight 17.2 ten thousand) 1000g, tricalcium phosphate 9.0g and the Sodium dodecylbenzene sulfonate 0.1g of deionized water 1800g, embodiment 1 preparation, one side stirs one side and is warming up to 60 ℃.

Then, deionized water 350g and polyvinyl alcohol 0.3g packed into mix in the monomer dispersion cup, again to wherein adding the styrene monomer 250g that has dissolved tert-butyl hydroperoxide-2-ethylhexyl carbonic ether 0.3g, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.After adding to this styrene monomer dispersion liquid in the container, be incubated and be warming up to 80 ℃ after 1 hour.

Then, deionized water 350g and polyvinyl alcohol 0.2g packed into mix in the monomer dispersion cup, again to wherein adding the styrene monomer 170g that has dissolved benzoyl peroxide 4.0g, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 90 minutes.

Then, added styrene monomer 1050g with 4 hours continuously with uniform velocity (adding speed 4.4g/ branch).

Then, add tricalcium phosphate 2.4g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃ of insulations 2 hours.Be cooled to 100 ℃ then, divide 2 times, each 110g to be pressed into butane (i/n is than=4/6), keep carrying out in 10 hours the dipping of whipping agent as whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.The weight-average molecular weight of this polymer particle is 22.5 ten thousand.Carry out classification, surface-coated, pre-frothing and molding according to method similarly to Example 1 then.

Embodiment 3

Pack in 5 liters withstand voltage stirred vessel deionized water 200g, regenerated phenylethene resin beads 200g, tricalcium phosphate 1.8g and Sodium dodecylbenzene sulfonate 0.02g, one side stirs one side and is warming up to 85 ℃.

Then, deionized water 1800g and polyvinyl alcohol 1.9g packed into mix in the monomer dispersion cup, again to wherein adding the styrene monomer 1800g that has dissolved benzoyl peroxide 5.1g and Benzoyl Peroxide tert-butyl ester 1.55g, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid was added in the container with uniform velocity (adding speed 15g/ branch) with 3 hours, be incubated 2 hours.Be warming up to 100 ℃ then, divide 2 times, each 90g to be pressed into butane (i/n is than=4/6) as whipping agent.Be pressed into and be warming up to 115 ℃ after butane finishes, kept 10 hours, carry out the dipping of whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.The molecular-weight average of this polymer particle is 20.1 ten thousand.Then, according to method similarly to Example 1 carry out that classification, additive are surface-coated, pre-frothing and molding.

Comparative example 1

The preparation of＜nuclear 〉

Use sieve that the classification of mincing of the fine powder of embodiment 1 preparation is become the scope of 0.6～1.4mm, obtain regenerated phenylethene resin beads (weight-average molecular weight 17.2 ten thousand, proportion 1.02).

The preparation of＜reclaimed expandable particle 〉

With above-mentioned regenerated phenylethene resin beads 1000g, deionized water 1500g, polyvinyl alcohol 0.5g, tricalcium phosphate 5g and the Sodium dodecylbenzene sulfonate 0.08g internal volume of packing into is to stir in 4 liters the withstand voltage reactor, then, add with homomixer (special processing industry manufacturing) deionized water 500g, Sodium dodecylbenzene sulfonate 0.06g and toluene 5g are stirred the dispersion liquid that formed in 5 minutes, after being warming up to 90 ℃, divide 2 times, each 45g to be pressed into butane (i/n is than=4/6) as whipping agent.Keep being warming up to 115 ℃ after 1 hour, kept 10 hours, carry out the dipping of whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.Then, according to method similarly to Example 1 carry out that classification, additive are surface-coated, pre-frothing and molding.

Embodiment 4

The preparation of＜reclaimed expandable particle 〉

Pack in 5 liters withstand voltage stirred vessel regenerated phenylethene resin beads 700g, tricalcium phosphate 6.0g and the Sodium dodecylbenzene sulfonate 0.06g of deionized water 500g, embodiment 1 preparation, one side stirs one side and is warming up to 85 ℃.

Then, deionized water 1300g and polyvinyl alcohol 1.4g packed into mix in the monomer dispersion cup, add the styrene monomer 1300g that has dissolved benzoyl peroxide 3.7g and Benzoyl Peroxide tert-butyl ester 1.12g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid was added in the container with uniform velocity (adding speed 15g/ branch) with 3 hours, be incubated 2 hours.Add then with homomixer deionized water 400g, Sodium dodecylbenzene sulfonate 0.12g and hexabromocyclododecane 60g are stirred the fire retardant dispersion liquid that formed in 30 minutes.Be warming up to 100 ℃ after adding this fire retardant dispersion liquid, (i/n is than=4/6 to divide 2 times, each 90g to be pressed into butane.Down together) as whipping agent.Be warming up to 115 ℃ after being pressed into butane, kept 10 hours, carry out the dipping of whipping agent.

After being cooled to room temperature, take out the regeneration flame-retardancy styrene resin particle that has flooded fire retardant and whipping agent, dehydrate.The molecular-weight average of this polymer particle is 22.5 ten thousand.Then, carry out classification, surface-coated, pre-frothing and molding according to method similarly to Example 1.

Embodiment 5

The preparation of＜reclaimed expandable particle 〉

Pack in 5 liters withstand voltage stirred vessel styrene resin particles (weight-average molecular weight 17.2 ten thousand) 1000g, tricalcium phosphate 9.0g and the Sodium dodecylbenzene sulfonate 0.1g of deionized water 1300g, embodiment 1 preparation, one side stirs one side and is warming up to 60 ℃.

Then, deionized water 350g and polyvinyl alcohol 0.3g packed into mix in the monomer dispersion cup, add the styrene monomer 250g that has dissolved tert-butyl hydroperoxide-2-ethylhexyl carbonic ether 0.3g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 80 ℃ after 1 hour.

Then, deionized water 350g and polyvinyl alcohol 0.2g packed into disperseed in the monomeric container, add the styrene monomer 170g that has dissolved benzoyl peroxide 4.0g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 90 minutes.

Then, add tricalcium phosphate 2.4g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃ of insulations 2 hours then., be cooled to 100 ℃, add with homomixer deionized water 500g, Sodium dodecylbenzene sulfonate 0.15g and hexabromocyclododecane 75g are stirred the fire retardant dispersion liquid that formed in 30 minutes thereafter.After adding the fire retardant dispersion liquid, divides 2 times, each 110g to be pressed into butane (i/n is than=4/6) as whipping agent, the dipping of fire retardant and whipping agent was carried out in maintenance in 10 hours.

After being cooled to room temperature, take out the regeneration flame-retardancy styrene resin particle that has flooded fire retardant and whipping agent, dehydrate.The weight-average molecular weight of this polymer particle is 22.8 ten thousand.Then according to method similarly to Example 1 carry out that classification, additive are surface-coated, pre-frothing and frothing mold.

Comparative example 2

The preparation of＜nuclear 〉

With sieve the classification of mincing of the fine powder of embodiment 1 preparation is become the scope of 0.6～1.4mm, obtain regenerated phenylethene resin beads (weight-average molecular weight 17.2 ten thousand, proportion 1.02).

The preparation of＜reclaimed expandable particle 〉

With above-mentioned regenerated phenylethene resin beads (weight-average molecular weight 17.2 ten thousand, proportion 1.02) 1000g, deionized water 1500g, polyvinyl alcohol 0.5g, tricalcium phosphate 5g and the Sodium dodecylbenzene sulfonate 0.08g internal volume of packing into is 4 liters withstand voltage reactor, stir, add then with the dispersion liquid of homomixer (special processing industry manufacturing) deionized water 500g, Sodium dodecylbenzene sulfonate 0.06g and toluene 5g and hexabromocyclododecane 30g stirring formation in 30 minutes, after being warming up to 90 ℃, divide 2 times, each 45g to be pressed into butane (i/n is than=4/6) as whipping agent.Keep being warming up to 115 ℃ after 1 hour, kept 10 hours, carry out the dipping of whipping agent.

After being cooled to room temperature, take out the regeneration flame-retardancy styrene resin particle that has flooded whipping agent, dehydrate.Then, according to method similarly to Example 1 carry out that classification, additive are surface-coated, pre-frothing and frothing mold.

Evaluation Example 1

Adopt HPLC to measure weight-average molecular weight in an embodiment.

In addition, measure surface smoothing rate and flexural strength by the following stated.

(1) surface smoothing rate

The surface smoothing rate of molded foam is be coated with very thin printing ink with roller on the surface of moulded parts, and this surface portion is placed in the image-processing system, obtains the black area partly with respect to the total area, with this as the surface smoothing rate.

(2) flexural strength

Bending strength test is to use the frothing mold body of density 0.02g/l, and (300 * 25 * 20mm) carry out according to the JIS-K7221 standard.

The evaluation result of embodiment shown in the table 1 1～5 and comparative example 1,2.

Table 1

	Reworked material/virgin material (wt%)	The weight-average molecular weight Mw1 of nuclear	The weight-average molecular weight Mw2 that particle is all	Mw1/ Mw2	Cross macroparticle (Wt%)	Surface smoothing rate (%)	Flexural strength (MPa)
								Embodiment 1	35/65	172000	223000	0.77	0.8	93	0.23
Embodiment 2	40/60	172000	225000	0.70	1.8	96	0.26
								Embodiment 3	10/90	172000	201000	0.86	12.8	91	0.25
Comparative example 1	100/0	172000	-	-	1.4	78	0.18
								Embodiment 4	35/65	172000	225000	0.76		92	0.23
Embodiment 5	40/60	172000	22800	0.75		94	0.26
								Comparative example 2	100/0	172000	-	-		73	0.26

[polymerization starter is to the influence of the manufacturing processed of reclaimed expandable styrene resin particles]

Embodiment 6

The preparation of＜nuclear 〉

Making foamed styrene with 220 ℃ hot blasts is that resin molding (changing into the moulded work that Ha イ PVC-ズ SSB-HX obtains that industry (strain) is made by Hitachi) shrinks, and obtains the constrictor of apparent specific gravity 0.8, size 500mm * 400mm * 100mm and the about 16kg of weight.Use has been installed the pulverizer (ZA-560 type pulverizer, the ホ of Co., Ltd.-ライ trade(brand)name) of the sieve of 10mm with this constrictor coarse reduction.The maximum length that the meal that obtain this moment minces is about 10mm, and volume weight is 0.65.Then, pack in enjoying She Er mixing machine (Mitsui three pond chemical industry are made, FM10B) this meal mince talcum (woods changes into manufacturings, ミ Network ロホワイト #5000) 20g and the ethylenebisstearamide 0.6g of 2000g and median size 10 μ m were with the rotating speed mixing of 2000rpm 2 minutes.Use has the 30mm forcing machine (T pattern head, sheet width 300mm, sheet thickness 1mm) of venting hole, and one side is with the speed drawing sheet material roughly the same with extruded velocity, and one side will be minced by the meal of talcum and ethylenebisstearamide lining and melt extrude.Before the cooling curing, with respect to extrude direction flatly with cylinder be provided with 1mm at interval, the slit of dark 0.5mm, cut off into about 10～15cm with stapling machine behind the cooling curing.Then, with the pulverizer (VM-16 type pulverizer, the オリエ of Co., Ltd. Application ト trade(brand)name) of the sieve that 2mm is installed that the cut off machine fine powder of resulting sheet phenylethylene resin series is broken.Use sieve that the classification of mincing of this fine powder is become the scope of 0.6～1.2mm, make the regenerated phenylethene resin beads.

The weight-average molecular weight of this regenerated phenylethene resin beads is 16.9 ten thousand, and proportion is 0.91.

The preparation of＜reclaimed expandable particle 〉

Pack in 5 liters withstand voltage stirred vessel deionized water 1900g, above-mentioned regenerated phenylethene resin beads 1100g, tricalcium phosphate 12.0g and Sodium dodecylbenzene sulfonate 0.09g, one side stirs one side and is warming up to 75 ℃.

Then, deionized water 400g and polyvinyl alcohol 1.3g packed into mix in the monomer dispersion cup, add the styrene monomer 200g that has dissolved Benzoyl Peroxide tert-butyl ester 0.2g and benzoyl peroxide 2.9g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 60 minutes.Use 5 hours then and add styrene monomer 900g continuously with uniform velocity (3.0g/ branch).

Subsequently, add tricalcium phosphate 2.2g, Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 2 hours.Be cooled to 100 ℃ then, divide 2 times, each 180g be pressed into butane (i/n is than=4/6, weight ratio, down with) as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.The molecular-weight average of this polymer particle is 27.0 ten thousand.

Then, with the sieve of mesh size 0.6～1.7mm with this polymer particle classification, add Zinic stearas 0.1% (weight), hardened castor oil 0.1% (weight) with respect to resulting resin particle and carry out surface-coatedly, obtain the reclaimed expandable styrene resin particles.

Embodiment 7

Change the benzoyl peroxide amount among the embodiment 6 into 2.3g, in addition operate similarly to Example 6, obtain the reclaimed expandable styrene resin particles.At this moment, the weight-average molecular weight of resulting reclaimed expandable styrene resin particles is 32.2 ten thousand.

Embodiment 8

Change the benzoyl peroxide amount among the embodiment 6 into 1.65g, in addition operate similarly to Example 6, obtain the reclaimed expandable styrene resin particles.At this moment, the weight-average molecular weight of resulting reclaimed expandable styrene resin particles is 43.3 ten thousand.

Evaluation Example 2

In embodiment 6～8, measure the weight-average molecular weight of skin section by the following stated.

The molecular weight of expandable styrene resin beads is measured particle foaming back.Use is foamed to the part of the resin particle of 50ml/g, and one side is examined under a microscope, and one side is divided into 9 equal portions with razor with particle 10 by shown in Figure 1.Mensuration is positioned at the weight-average molecular weight of the skin section S of the most surperficial side.

Molecular weight is to carry out HPLC by following condition to measure.

Post: GL-R400M (10.7 * 300mm) 2 of Φ

Column temperature: room temperature

Eluant: THF

Flow: 2.0ml/ branch

Detector: UV 220nm

Injection rate: 100 μ l

The evaluation result of embodiment shown in the table 2 6～8.

Table 2

	Polymerization starter amount (g)	Reworked material/virgin material (wt%)	The weight-average molecular weight Mw1 of nuclear	The weight-average molecular weight Mw2 that particle is all	Mw1/Mw2 ×100	Mw1/ Mw2	Surface smoothing rate (%)	Flexural strength (MPa)
									Embodiment 6	2.9	50/50	169000	270000	160	0.63	94	0.32
Embodiment 7	2.3	50/50	169000	322000	191	0.52	92	0.34
									Embodiment 8	1.65	50/50	169000	433000	256	0.39	90	0.32

[influence of oxygen concn in the manufacturing processed of reclaimed expandable styrene resin particles]

Embodiment 9

The preparation of＜nuclear 〉

Operation similarly to Example 1, the regenerated phenylethene that obtains weight-average molecular weight 20.0 ten thousand is a resin.

The preparation of＜reclaimed expandable particle 〉

Add deionized water 1700g, above-mentioned regenerated phenylethene resin beads (nuclear) 1000g, tricalcium phosphate 10.0g and Sodium dodecylbenzene sulfonate 0.08g in 5 liters withstand voltage stirred vessel, one side stirs one side and is warming up to 70 ℃.

Subsequently, deionized water 300g and polyvinyl alcohol 0.36g packed into mix in the monomer dispersion cup, add the styrene monomer 300g that has dissolved benzoyl peroxide 2.70g and tert-butyl hydroperoxide sec.-propyl one carbonic ether 0.20g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.With 30 minutes this styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 30 minutes.

Then, added styrene monomer 700g with 3 hours continuously with uniform velocity.At this moment, will oxygen concn be remained on 2～5% (volumes) with in the withstand voltage stirred vessel of nitrogen purging.Percent polymerization after 3 hours is 85%.

Then, add tricalcium phosphate 2.4g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 2 hours.Also remain on above-mentioned oxygen concn during this.Percent polymerization after 2 hours is more than 98% or 98%.Subsequently, be cooled to 100 ℃, divide 2 times, each 100g to be pressed into butane (i/n is than=4/6) as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

After being cooled to room temperature, take out the styrene resin particles of having flooded whipping agent, dehydrate.

Then, with the sieve of mesh size 1.7mm with this polymer particle classification, the sieve of using mesh size 0.6mm again is with the above-mentioned further classification of polymer particle by sieve, add Zinic stearas 0.1% (weight), hardened castor oil 0.1% (weight) and carry out surface-coatedly for remaining in resin particle on the sieve, obtain the reclaimed expandable styrene resin particles.

In an embodiment, percent polymerization is to gather resin particle in synthetic to use that array apparatus and condition are measured down.

Determinator: (strain) Hitachi makes

Eluant: acetonitrile/distilled water=70/30, flow: 1ml/ branch

Detector: UV 230nm

Post: Inertsil ODS-2

Embodiment 10

The preparation of＜reclaimed expandable particle 〉

In 5 liters withstand voltage stirred vessel, pack into deionized water 1700g, according to regenerated phenylethene resin beads (nuclear) 1000g, tricalcium phosphate 10.0g and the Sodium dodecylbenzene sulfonate 0.08g of the method preparation identical with embodiment 9, one side stirs simultaneously and is warming up to 70 ℃.

Then, deionized water 300g and polyvinyl alcohol 0.36g packed into mix in the monomer dispersion cup, add the styrene monomer 300g that has dissolved benzoyl peroxide 2.70g and tert-butyl hydroperoxide sec.-propyl one carbonic ether 0.20g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.With 30 minutes this styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 30 minutes.

Then, added styrene monomer 700g with 3 hours continuously with uniform velocity.At this moment, will be with in the withstand voltage stirred vessel of nitrogen purging, oxygen concn remained on 0.5% (volume) or below 0.5% (volume).Percent polymerization after 3 hours is 93%.

Then, add tricalcium phosphate 2.4g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃ then, be incubated 2 hours.Also remain on above-mentioned oxygen concn during this.Percent polymerization after 2 hours is more than 98% or 98%.Subsequently, be cooled to 100 ℃, divide 2 times, each 100g to be pressed into butane (i/n is than=4/6) as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

After being cooled to room temperature, take out the styrene resin particles of having flooded whipping agent, dehydrate.Then according to method similarly to Example 9 carry out classification, with surface-coated, foaming of additive and molding.

Embodiment 11

The preparation of＜reclaimed expandable particle 〉

In embodiment 10, use nitrogen purging from the beginning, the oxygen concn in the reactive tank is remained on 1% (volume) or below 1% (volume), in addition operate manufacturing reclaimed expandable particle similarly to Example 10.

Embodiment 12

The preparation of＜reclaimed expandable particle 〉

As a comparative example, do not reduce oxygen concn, preparation reclaimed expandable styrene resin particles.

In 5 liters withstand voltage stirred vessel, pack into deionized water 1700g, according to reclaimed expandable styrene resin particles 1000g, tricalcium phosphate 10.0g and the Sodium dodecylbenzene sulfonate 0.08g of the method preparation identical with embodiment 1, one side stirs one side and is warming up to 70 ℃.

Then, added styrene monomer 700g with 3 hours continuously with uniform velocity.At this moment, in the withstand voltage stirred vessel of nitrogen purging, carry out polymerization, oxygen concn is 17～20% (volumes).The percent polymerization of this moment is 85%.

Subsequently, add tricalcium phosphate 2.4g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 2 hours.Be cooled to 100 ℃ then, divide 2 times, each 100g to be pressed into butane (i/n is than=4/6) as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

Embodiment 13

The preparation of＜nuclear 〉

Operate similarly to Example 6, obtain the regenerated phenylethene resin beads of weight-average molecular weight 16.9 ten thousand, proportion 0.91.

The preparation of＜reclaimed expandable particle 〉

Add deionized water 1900g, above-mentioned regenerated phenylethene resin beads (nuclear) 1100g, tricalcium phosphate 12.0g and Sodium dodecylbenzene sulfonate 0.09g in 5 liters withstand voltage stirred vessel, one side stirs one side and is warming up to 75 ℃.

Subsequently, deionized water 400g and polyvinyl alcohol 1.3g packed into mix in the monomer dispersion cup, add the styrene monomer 200g that has dissolved tert-butyl peroxide ester 0.2g and benzoyl peroxide 2.9g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.With 30 minutes this styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 60 minutes.

Then, added styrene monomer 900g with 5 hours continuously with uniform velocity (3.0g/ branch).At this moment, in the withstand voltage stirred vessel of nitrogen purging, oxygen concn is remained on 2～5% (volumes).The styrene monomer containing ratio of this moment is 15% (percent polymerization 85%).

Then, add tricalcium phosphate 2.2g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 2 hours.Then, be cooled to 100 ℃, divide to be pressed into butane (i/n is than=4/6) 180g for 2 times as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.Carry out classification, surface-coated, pre-frothing and molding according to method similarly to Example 9 then.

Embodiment 14

The preparation of＜reclaimed expandable particle 〉

Regenerated phenylethene resin beads (nuclear) 1100g, the tricalcium phosphate 12.0g and the Sodium dodecylbenzene sulfonate 0.09g that in 5 liters withstand voltage stirred vessel, add deionized water 1900g, embodiment 13 preparations.Then, in the withstand voltage stirred vessel of nitrogen purging, making oxygen concn is 2～5% (volumes).One side stirs one side and is warming up to 75 ℃ then.

Then, added styrene monomer 900g with 5 hours continuously with uniform velocity (3.0g/ branch).At this moment, in the withstand voltage stirred vessel of nitrogen purging, oxygen concn is remained on 2～5% (volumes).The styrene monomer containing ratio of this moment is 13% (percent polymerization 87%).

Then, add tricalcium phosphate 2.2g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 2 hours.Then, be cooled to 100 ℃, divide to be pressed into butane (i/n compares=4/6, and weight ratio is same down) 180g for 2 times as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

After being cooled to room temperature, take out the reclaimed expandable styrene resin particles of having flooded whipping agent, dehydrate.Then according to method similarly to Example 9 carry out classification, with surface-coated, foaming of additive and molding.

Embodiment 15

The preparation of＜reclaimed expandable particle 〉

Regenerated phenylethene resin beads (nuclear) 1100g, the tricalcium phosphate 12.0g and the Sodium dodecylbenzene sulfonate 0.09g that in 5 liters withstand voltage stirred vessel, add deionized water 1900g, embodiment 13 preparations.In the withstand voltage stirred vessel of nitrogen purging, making oxygen concn is 0.5～1% (volume).One side stirs one side and is warming up to 75 ℃ then.

Then, deionized water 400g and polyvinyl alcohol 1.3g packed into mix in the monomer dispersion cup, add the styrene monomer 200g that has dissolved tert-butyl peroxide ester 0.2g and benzoyl peroxide 2.9g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.With 30 minutes this styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 60 minutes.

Then, added styrene monomer 900g with 5 hours continuously with uniform velocity (3.0g/ branch).At this moment, in the withstand voltage stirred vessel of nitrogen purging, oxygen concn is remained on 0.5～1% (volume).The styrene monomer containing ratio of this moment is 10% (percent polymerization 90%).

Embodiment 16

As a comparative example, do not carry out the nitrogen purging in the withstand voltage stirred vessel in embodiment 13, in addition operation similarly to Example 13 obtains the reclaimed expandable styrene resin particles.The oxygen concn of this moment is 17～20% (volumes).

Evaluation Example 3

In embodiment 9～16, measure the weight-average molecular weight of surface portion and centre portions by the following stated.

With the reclaimed expandable styrene resin particles in saturated steam, foam to the volume multiple be 50ml/g.

Get 2～3 expanded particles arbitrarily, with razor half of particle 1 equally spaced is divided into 5 equal portions, form

part

1,2,3,4 and 5 from the outside by shown in Figure 2.For the part 1 (surface portion) of the most surperficial side, its former state is taken out, for the most inboard part 5 (centre portions), be divided into 5 equal portions, take out its center, determining molecular weight with entry needle.For part 3 (from center 3/5 part), take out the center same, determining molecular weight with part 5 with entry needle.

The fusion rate is that the disrumpent feelings bead on the broadwise out section of using when moulded work cut is represented with the ratio of not disrumpent feelings bead.

Fusion rate (%)=disrumpent feelings bead number/(disrumpent feelings bead number+not disrumpent feelings bead number)

The evaluation result of embodiment shown in the table 3 9～16.

In addition, the surface portion of the reclaimed expandable styrene resin particles that obtains for embodiment 15 and 16 adopts gel permeation chromatography (GPC) to record spectrogram (GPC spectrogram).At this moment, use is measured with lower device and condition.

Determinator: (strain) Hitachi makes

Eluant: THF, flow: 2ml/ branch

Detector: UV 220nm

Post: Hitachi changes into industry (strain) and makes 2 of GL-R400M

Fig. 3 (a) and the GPC spectrogram of embodiment 15 and 16 (b) is shown respectively.As shown in the figure, the particle to embodiment 15 such molecular weight sharply raise has bimodal in its GPC spectrogram.Bimodal is to form owing to the ratio of high molecular polymer is more.On the other hand, the particle to embodiment 16 such molecular weight raise bit by bit though can observe some swellings on the GPC spectrogram, does not have flex point, does not promptly form acromion, does not form bimodal yet.

[adding the influence of inorganics and/or organic system lubricant] for nuclear

Embodiment 17

The preparation of＜nuclear 〉

Making foamed styrene with 220 ℃ hot blasts is that resin molding (changing into the moulded work that Ha イ PVC-ズ SSB-HX obtains that industry (strain) is made by Hitachi) shrinks, and obtains the constrictor of apparent specific gravity 0.75, size 500mm * 400mm * 100mm and weight 15kg.Use has been installed the pulverizer (ZA-560 type pulverizer, the ホ of Co., Ltd.-ライ makes) of the sieve of 10mm with this constrictor coarse reduction.The maximum length that the meal that obtain this moment minces is about 10mm, and volume weight is 0.5.

Then, pack in enjoying She Er mixing machine (Mitsui three pond chemical industry are made, FM10B) this meal the mince talcum of 2000g and median size 10 μ m (woods change into Co., Ltd. makes, ミ Network ロホワイト #5000) 20g and ethylenebisstearamide 0.6g mixed 2 minutes with the rotating speed of 2000rpm.Use has the 30mm forcing machine (T pattern head, sheet width 300mm, sheet thickness 1mm) of venting hole, one side is with the speed drawing sheet material roughly the same with extruded velocity, and one side will be minced by talcum and the surface-coated meal of ethylenebisstearamide and melt extrude.

Before the cooling curing, with respect to extrude direction flatly with cylinder be provided with 1mm at interval, the slit of degree of depth 0.5mm, cut off into about 10～15cm with stapling machine behind the cooling curing.Then, with the pulverizer (VM-16 type pulverizer, the オリエ of Co., Ltd. Application ト trade(brand)name) of the sieve that 2mm is installed that the cut off machine fine powder of resulting sheet phenylethylene resin series is broken.With sieve the classification of mincing of this fine powder is become the scope of 0.6～1.0mm, make the regenerated phenylethene resin beads.

The preparation of＜reclaimed expandable particle 〉

Pack in 5 liters withstand voltage stirred vessel above-mentioned regenerated phenylethene resin beads 1100g, deionized water 1500g, tricalcium phosphate 12.0g and Sodium dodecylbenzene sulfonate 0.09g, one side stirs one side and is warming up to 70 ℃.

Then, deionized water 350g and polyvinyl alcohol 0.36g packed into mix in the monomer dispersion cup, add the styrene monomer 200g that has dissolved tert-butyl peroxide ester 3.2g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 90 minutes.Use 3 hour time to add styrene monomer 600g continuously then with uniform velocity (3.3g/ branch).

Subsequently, add tricalcium phosphate 2.4g, Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 2 hours.Be cooled to 100 ℃ then, divide 2 times, each 160g to be pressed into butane (weight ratio of Trimethylmethane/normal butane=4/6) as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

After being cooled to room temperature, take out the expandable styrene resin beads that has flooded whipping agent, dehydrate.The sieve of using mesh size 1.70mm and 0.60mm then is this resin particle classification, the 2240g resin particle that obtains.In resulting resin particle, add Zinic stearas 1.12g successively, hardened castor oil 2.24g mixes.

Then, with the sieve of mesh size 1.70mm and 0.60mm with this resin particle classification, the 2240g resin particle that obtains.In resulting resin particle, add Zinic stearas 1.12g successively, hardened castor oil 2.24g mixes, and obtains the reclaimed expandable styrene resin particles.

With the pre-frothing of resulting reclaimed expandable styrene resin particles to 50ml/g, after about 18 hours of the slaking, to use foamed styrene be resin carries out molding with mould machine (ダイセ Application industry manufacturing VS-300) with the molding pressure of 0.08MPa, obtains moulded parts.

Embodiment 18

Use the 40g talcum in embodiment 17, do not use ethylenebisstearamide, in addition operation similarly to Example 17 obtains reclaimed expandable styrene resin particles and moulded parts.

Embodiment 19

Use the 1.0g ethylenebisstearamide in embodiment 17, do not use talcum, in addition operation similarly to Example 17 obtains reclaimed expandable styrene resin particles and moulded parts.

Embodiment 20

In embodiment 17, change talcum the lime carbonate of median size 12 μ m into, in addition operation similarly to Example 17 obtains reclaimed expandable styrene resin particles and moulded parts.

Embodiment 21

As a comparative example, do not use talcum and ethylenebisstearamide in embodiment 17, in addition operation similarly to Example 17 obtains reclaimed expandable styrene resin particles and moulded parts.

Evaluation Example 4

In embodiment 17～21, cell diameter is, cuts expanded particle with sharp cutting knife, with microscope this section taken a picture, and measures the diameter of 10 abscesses by resulting photo, with their mean value as cell diameter.

The evaluation result of embodiment shown in the table 4 17～21.

Table 4

[influence of the particle diameter of nuclear (regenerated phenylethene resin beads)]

Embodiment 22

The preparation of＜nuclear 〉

Making fine powder according to similarly to Example 1 method minces.The sieve that uses mesh size 1.40mm and 0.85mm is made the regenerated phenylethene resin beads with the classification of mincing of this fine powder.The median size of resulting regenerated phenylethene resin beads is 1170 μ m, is 0.4% (weight) smaller or equal to the content of the particle of 300 μ m.

The preparation of＜reclaimed expandable particle 〉

Subsequently, deionized water 350g and polyvinyl alcohol 0.36g packed into mix in the monomer dispersion cup, add the styrene monomer 300g that has dissolved tert-butyl hydroperoxide-2-ethylhexyl carbonic ether 0.25g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated 30 minutes then.

Then, deionized water 300g and polyvinyl alcohol 0.24g packed into mix in the monomer dispersion cup, add the styrene monomer 200g that has dissolved benzoyl peroxide 3.0g again, use homomixer (special machine chemical industry is made) to stir 120 seconds, make that styrene monomer is fine to be disperseed (mean diameter 10～100 μ m of monomer oil droplet) with the rotating speed of 5800rpm.This styrene monomer dispersion liquid is added in the container, be incubated and be warming up to 90 ℃ after 90 minutes.

Then, added styrene monomer 600g with 3 hours continuously with uniform velocity (3.3g/ branch).

Then, add tricalcium phosphate 2.4g and Sodium dodecylbenzene sulfonate 0.05g, be warming up to 115 ℃, be incubated 5 hours.Subsequently, be cooled to 100 ℃, divide 2 times, each 80g be pressed into butane (i/n is than=4/6, weight ratio, down with) as whipping agent.Kept 10 hours, and carried out the dipping of whipping agent.

Then, the sieve of using mesh size 2.00mm and 0.85mm obtains the 2210g resin particle with this resin particle classification.For resulting resin particle add Zinic stearas 1.11g successively, hardened castor oil 1.11g mixes, and obtains the reclaimed expandable styrene resin particles.

Embodiment 23

The preparation of＜nuclear 〉

The fine powder for preparing phenylethylene resin series according to similarly to Example 22 method minces, and the sieve that uses mesh size 1.70mm and 0.60mm is made the regenerated phenylethene resin beads with its classification.The median size of resulting regenerated phenylethene resin beads is 1260 μ m, and the content of the particle that 300 μ m are following is 0.6% (weight).

The preparation of＜reclaimed expandable particle 〉

Use above-mentioned regenerated phenylethene resin beads to operate similarly to Example 22, the sieve that uses mesh size 2.20mm and 0.60mm obtains the 2160g resin particle with resulting resin particle classification.For resulting resin particle add Zinic stearas 1.80g successively, hardened castor oil 1.08g mixes, and obtains the reclaimed expandable styrene resin particles.

Use resulting reclaimed expandable styrene resin particles, carry out pre-frothing and molding similarly to Example 22, obtain moulded parts.

Embodiment 24

The preparation of＜nuclear 〉

The fine powder for preparing phenylethylene resin series according to similarly to Example 22 method minces, and the sieve that uses mesh size 1.40mm and 0.43mm is made the regenerated phenylethene resin beads with its classification.The median size of resulting regenerated phenylethene resin beads is 1060 μ m, and the content of the particle that 300 μ m are following is 2.4% (weight).

The preparation of＜reclaimed expandable particle 〉

Use above-mentioned regenerated phenylethene resin beads to operate similarly to Example 22, the sieve of using mesh size 1.70mm and 0.50mm obtains the 2110g resin particle with resulting resin particle classification.For resulting resin particle add Zinic stearas 1.60g successively, hardened castor oil 1.06g mixes, and obtains the reclaimed expandable styrene resin particles.

Evaluation Example 5

In embodiment 22～24, measure median size by the following stated.

(1) with JIS standard sieve (JIS Z 8801) by mesh size shown below (unit: the overlapping arrangement of order mm), put plate in the bottom.

Order is 2.00,1.70,1.40,1.18,1.00,0.85,0.71,0.60,0.50,0.425,0.355,0.30,0.25 from top to bottom

(2) weighing 100g test portion puts it on the sieve of the top one-level.

(3) begin to sieve from upper level, no longer fall from sieve up to test portion.To be added in the sieve of next stage by the test portion that falls on the sieve, so repeatable operation is until reaching next stage sieve.

(4) measure each sieve and go up residual test portion weight.

(5) obtain the size distribution that each sieves by following formula.

Size distribution (%) of each sieve=(test portion weight and total amount that residual test portion weight on the sieve/on the sieve of all grades is residual) * 100

(6) obtain the aggregate-value of size distribution in proper order by the big sieve of mesh.

(7) being transverse axis with size of particles (=sieve mesh size), is the longitudinal axis with the aggregate-value of size distribution, and the data of obtaining in above-mentioned (6) are marked and drawed out.Then the each point that marks is connected into level and smooth curve.

Size of particles when (8) being read aggregate-value and be 50 (%) by above-mentioned curve is with the numerical value that the reads median size as this test portion.

The evaluation result of embodiment shown in the table 5 22～24.

Table 5

Application on the industry

Adopt the present invention, it is molded foam that the outward appearance of moulded parts and/or the reclaimed expandable styrene resin particles and the regenerated phenylethene of excellent strength can be provided.

Claims

1. reclaimed expandable styrene resin particles, it is characterized in that, it contains by the weight-average molecular weight of measuring by the HPLC assay method is that 100,000～250,000 regenerated phenylethene is the nuclear of resin formation and the fresh phenylethylene resin series of interior this nuclear of bag, be divided into 5 timesharing such as grade from the surface of particle to the center, the weight-average molecular weight of the surface portion that is formed to 1/5 place by the surface is higher more than 50,000 than the weight-average molecular weight that is reached the centre portions that 1/5 place forms by mind-set surface in above-mentioned, has bimodal or acromion in the spectrogram that the employing gel permeation chromatography of described surface portion obtains.

2. the regenerated phenylethene that the described reclaimed expandable styrene resin particles foaming of claim 1 is obtained is a foamed beads.

3. be that the regenerated phenylethene that the foamed beads molding obtains is a molded foam with the described regenerated phenylethene of claim 2.