CN1289797A - Chlorinated ethylene resin/cellulose mixer: compositions, method, compounded materials and products thereof - Google Patents

Abstract

A composition and method for manufacturing powder-extruded mixture including at least one chloroethylene resin and cellulosic material is provided. More especially, the invention provides a composition and method for manufacturing free flowing powder-extruded mixture including PVC and wood flour (WF) for producing foaming or non-foaming extrudate. The composition containing not more than 25 Wt.% water is doped in the method. A method for producing foaming extrudate is also provided, wherein the cooling liquid is used for improving expansion ratio of the foamed plastic. The invention provides eventually a composition containing extruded thermo-plastic substrate and tread glue line layers including PVC/WF composition with at least one layer placed thereon.

Description

Ethylene chloride base resin/cellulose blending thing: composition, method, mixture and goods thereof

The present invention relates to contain the composition of the blend of ethylene chloride base resin (as polyvinyl chloride) and cellulosic materials (as wood powder), it has excellent melt flow and melt strength, to form the foaming and the extrudate that do not foam of high-quality apperance.In particular, the present invention relates to the particular composition of cellulosic materials of the formation free flowing powder of ethylene chloride base resin, thermo-stabilizer, lubricant, polymer processing aid and high level (greater than about 24 weight % of total amount).These compositions are easy to extrude, and the composite product that can be shaped to various foaming and not foam, and it serves many purposes, and comprise building and structural member, as grille, baffle plate, cover plate, window frame, threshold and door.The present invention also relates to the preparation method of the powdered mixture of these blend compositions, these powdered mixture are easy to extrude, thereby have solved the predrying or granulation problem in the present practice.The present invention relates to prepare the method for free flowing powder, originally the nearly 25 weight % that wherein add the component total amount can be water.The present invention also relates to the preparation method of the foaming extrudate of expansion ratio raising.In addition, the present invention relates to contain the mixture of the present composition.

Typically, when the wood powder of high weight percentage and PVC blend, the gained compound shows that to contain temperature amount height, powder treatment poor performance (flow of powder moment and tap density are low), melt flow and melt strength poor, and the surface irregularity of finished product, marginal laceration.Up to now, the past is a wood powder at about 20 weight % that the trial aspect wood powder and PVC is confined to final composition.Wood powder content surpasses at 20% o'clock, and these problems have enlarged, and can not easily extrude.

Someone by in the preparation powder blend in wood powder with predrying wood powder (" WF ") before PVC combines, extruding before predrying powder blend or by at first the granulation of PVC/WF powder blend being solved these problems.But these methods are costliness but also consuming time not only.

At United States Patent (USP) 5,847, in 016, Cope has described the two-step approach of preparation PVC and wood powder mixture, and wherein the wood powder particle is by PVC institute's packing and granulation.Subsequently these pellets are mixed with extra polyvinyl chloride resin and whipping agent, and extrude and be finished product.Think that packing has prevented the suction in the particle, suction can influence the ability that the PVC/WF mixture is extruded into porous plastics.In disclosed PVC/WF composition, the overall weight percent of wood powder only is limited to about 17%.

In Japanese publication JP95-315193, people such as Murakami have described foamable vinyl chloride resin/wood powder composition, and it forms component becomes pellet through foaming, and extrudes or be molded as product subsequently.In the composition of Murakami, total amount and the PVC total amount of setting lubricant and processing aid are proportional.So the overall weight percent of lubricant and processing aid reduces with the rising of wood powder amount.Prove that as this paper these compositions can not easily directly be extruded into slick powdery extrudate.

Similarly, known in typical PVC prescription and adding WF simply.This causes the overall weight percent of several key ingredients (lubricant, polymer processing aid and whipping agent) significantly to reduce with the rising of WF amount.When this thing happens, we observed processing characteristics and reduce greatly.

We find so far, for the powder blend of the ethylene chloride base resin (for example PVC) Yu the cellulosic materials (for example WF) that are easy to be processed into the good foaming extrudate of outward appearance is provided, importantly will remain on the level suitable in the lubricant of blend composition total amount and the overall weight percent of polymer processing aid with its weight percentage in not containing the standard PVC foaming formulation of WF.So,, need improve the total amount of lubricant and processing aid simultaneously with the rising of cellulosic materials consumption.Be used to prepare the composition of powder composition described herein and cellulosic materials (hereinafter being expressed as " CM ") that method comprises high weight percentage, it is more than or equal to 24 weight % and at least a ethylene chloride base resin (hereinafter being expressed as " CVR ").These compositions not only can directly be extruded (so not needing composition at first granulation or predrying cellulosic materials component), and provide outward appearance good extrudate.Up to now, never know these compositions and method.

First target of the present invention provides the powder composition of extrudable ethylene chloride base resin/cellulose blending thing, and it can be easy to be extruded into foaming and foaming product not.Second target of the present invention provides the powder composition of extrudable polyvinyl chloride/wood powder blend, and it also is to be easy to be extruded into the foaming and the free flowing powder of foaming product not.The 3rd target of the present invention provides the preparation method of the powder composition of first target according to the present invention.The 4th target of the present invention provides the admixture of powder preparation of compositions method of second target according to the present invention, and wherein the nearly 25 weight % of the component total amount that adds in the method can be water, and these water can be removed subsequently.The 5th target of the present invention provides the preparation method of the foaming extrudate of expansion ratio raising.The 6th target of the present invention provides a kind of mixture, its contain base layer and at least one deck by the tread band that extrudable polyvinyl chloride/wood powder blend powders composition makes of second target according to the present invention.Can reach these targets and other target that will from following disclosing, show by the present invention.

Summary of the invention

In the present invention, generally do not reduce, the problem that contains more than or equal to extrudable ethylene chloride base resin/cellulosic materials (hereinafter being expressed as " CVR/CM ") powder composition of the cellulosic materials of 24 weight % that provides is provided with the amount of the cellulosic materials that adds composition by the gross weight mark that guarantees lubricant and polymer processing aid.Specifically, the invention provides when the overall weight percent of cellulosic materials changes between 24%-65%, the overall weight percent of whole lubricants is maintained at about between the 1.5%-5% in the powder composition, and the overall weight percent of polymer processing aid is maintained at about between the 3.5%-15%.In addition, the invention provides the preparation method of the powder composition of extrudable ethylene chloride base resin/cellulose blending thing, this powder composition is to be easy to be extruded into the foaming and the free flowing powder of foaming product not.The present invention also provides the preparation method of the powder blend of the whipping agent that contains one or more extrudates that are used to foam, and wherein can provide to be in excess in the nearly water of 25 weight % when adding blend component, otherwise be unfavorable for the whipping agent function of bringing into normal play.The present invention also provides the method for preparing the extrudate that foams, wherein with the surface of cooling fluid sclerosis foaming extrudate to improve the expansion ratio of foaming extrudate.The present invention also provides a kind of mixture, but its contain the base layer of extruding thermoplastic resins and at least one stratification thereon contain the tread band of extruding the free flowing powder blend composition of the present invention.

Therefore, a first aspect of the present invention provides extrudable ethylene chloride base resin/cellulose powder blend composition, and it comprises:

(a) at least a ethylene chloride base resin of 30-65 weight %;

(b) at least a thermo-stabilizer of 0.25-5 weight %;

(c) at least a lubricant of 1.5-5 weight %;

(d) at least a polymer processing aid of 3.5-15 weight %; With

(e) at least a cellulosic materials of 24-65 weight %.

Extrudable free flowing powder blend composition is provided in a second aspect of the present invention, and it comprises:

(a) at least a polyvinyl chloride resin of 40-55 weight %;

(b) at least a thermo-stabilizer of 0.5-1.5 weight %;

(c) at least a lubricant of 1.5-3 weight %;

(d) at least a polymer processing aid of 5-10 weight %;

(e) at least a wood powder of 34-52 weight %;

(f) at least a mineral filler of 3-15 weight %; With

(g) at least a whipping agent of 3 weight % at the most.

The preparation method of extrudable powder blend is provided in a third aspect of the present invention, may further comprise the steps:

(I) will comprise the mixture blend of following component:

(a) at least a ethylene chloride base resin of 30-65 weight %;

(b) at least a thermo-stabilizer of 0.25-5 weight %;

(c) at least a lubricant of 1.5-5 weight %;

(d) at least a polymer processing aid of 3.5-15 weight %; With

(e) at least a cellulosic materials that contains wet branch of 24-65 weight %.

(II) is in (I) blend step more than the elevated temperature to 50 ℃; With

(III) removes water vapour.

The preparation method of extrudable free flowing powder blend is provided in a fourth aspect of the present invention, may further comprise the steps:

(I) will comprise the mixture blend of following component:

(a) at least a polyvinyl chloride resin of 40-55 weight %;

(b) at least a thermo-stabilizer of 0.5-1.5 weight %;

(c) at least a lubricant of 1.5-3 weight %;

(d) at least a polymer processing aid of 5-10 weight %;

(e) at least a wood powder that contains wet branch of 34-52 weight %;

(f) at least a mineral filler of 3-15 weight %; With

(g) at least a whipping agent of 3 weight % at the most;

(II) is in (I) blend step more than the elevated temperature to 80 ℃; With

(III) removes water vapour so that the final water capacity in the powder blend is lower than 2.0 weight %.

The method for preparing the extrudate that foams is provided in a fifth aspect of the present invention, may further comprise the steps:

The extrudable free flowing powder blend that (I) will contain at least a whipping agent adds in the forcing machine;

(II) melted powder blend is to form melt;

(III) has the foaming extrudate at least one surface with formation from mouth mould melt extrusion;

(IV) is with the surface of cooling fluid sclerosis foaming extrudate, to improve the expansion ratio of foaming extrudate.

Provide a kind of mixture in a sixth aspect of the present invention, but it contains base layer and at least one stratification tread band that contains extrudable free flowing powder blend composition thereon of extruding thermoplastic resins, said composition comprises:

(a) at least a polyvinyl chloride resin of 40-55 weight %;

(b) at least a thermo-stabilizer of 0.5-1.5 weight %;

(c) at least a lubricant of 1.5-3 weight %;

(d) at least a polymer processing aid of 5-10 weight %;

(e) at least a wood powder of 34-52 weight %;

(f) at least a mineral filler of 3-15 weight %; With

(g) at least a whipping agent of 3 weight % at the most.

Extrudate, mouldings, sheet material, film, tubing are provided in another aspect of this invention, porous plastics, container, profiled material or other goods with above-mentioned admixture of powder composition of the present invention and method preparation.

Term " weight % " means weight fraction in the component of composition total weight at this.

Term " CVR " means " ethylene chloride base resin " as herein described at this.

Term " CM " means " cellulosic materials " as herein described at this.

Term " CVR/CM " means the material that comprises CVR and CM at this.

Term " phr " means umber in per 100 parts of weight CVR at this.

Term " the interpolation total amount of water " means water content in the CVR/CM component at this.

It is the material of gas or liquid physics attitude that term " fluid " means at this.

Detailed Description Of The Invention

The particular combinations that has now found that ethylene chloride base resin, thermo-stabilizer, lubricant, polymer processing aid and cellulosic materials can provide the admixture of powder composition of the cellulosic materials that contains high weight percentage, and it can be extruded into the good foaming of appearance and the extrudate that do not foam.Admixture of powder composition of the present invention contains 30-65 weight %, preferred 35-60 weight %, at least a ethylene chloride base resin of 40-55 weight % most preferably; 0.25-5 weight %, preferred 0.5-3 weight %, at least a thermo-stabilizer of 0.5-1.5 weight % most preferably; 1.5-5, preferred 1.5-4 weight %, at least a lubricant of 1.5-3 weight % most preferably; 3.5-15 weight %, preferred 4-12 weight %, at least a polymer processing aid of 5-10 weight % most preferably; With 24-65 weight %, preferred 30-60 weight %, at least a cellulosic materials of 34-52 weight % most preferably.

Be applicable to that ethylene chloride base resin of the present invention comprises polyvinyl chloride (" PVC "), chlorinated polyvinyl chloride (" CPVC ") and contains the multipolymer and the blend of vinyl chloride monomer.PVC is preferred ethylene chloride base resin, and it is common interchangeable heat thermoplastic polymer.In the preparation of polyvinyl chloride copolymer, also PVC can be combined with other vinyl monomer.These multipolymers can be linear copolymers, branched copolymers, graft copolymer, random copolymers, stereoregular multipolymer, segmented copolymer etc.

Can combine the monomer that forms vinyl chloride copolymer with vinylchlorid and comprise vinyl cyanide; Alpha-olefin is as ethene, propylene etc.; Chlorinated monomer is as vinylidene chloride; Acrylic ester monomer is as vinylformic acid, methyl acrylate, butyl acrylate, methyl methacrylate, acrylamide, Hydroxyethyl acrylate etc.; Styrene monomer is as vinylbenzene, alpha-methyl styrene, Vinyl toluene etc.; Vinyl-acetic ester; With other unsaturated vinyl monomer composition commonly used.

These monomeric consumptions can be up to about 50 moles of %, and itself and vinylchlorid balance are to provide the suitable ethylene chloride base resin that generates powder blend.Polyvinyl chloride forms many known polymer alloies, comprises for example polyvinyl chloride/nitrile-butadiene rubber; Polyvinyl chloride and the relevant fluorinated copolymers and the terpolymer of polyvinyl chloride or vinylidene chloride; The blend of polyvinyl chloride/alpha-methyl styrene-acrylonitrile copolymer; Polyvinyl chloride/polyethylene; Polyvinyl chloride/chlorinatedpolyethylene etc.Vinyl chloride resin component of the present invention comprises this PVC polymer alloy or PVC copolymer alloy.

To the major requirement of thermoplastic, polymeric materials basically is that it has enough thermoplasticity, mix, allow to be processed into the thermoplasticity extrudate to allow itself and cellulosic materials to melt, to form the rigid structure member that can further foam or not foam with the known conventional process tools of field of plastics processing.

Polyvinyl chloride homopolymer, multipolymer and polymer alloy can be available from Geon chemical companies, Avon lake, Ohio and Georgian Bay, Plaquemine, Louisiana.Preferred pvc material is that the K value is the polyvinyl chloride homopolymer between 50 to 67; Preferably use the processing foamed composition of K50,, can obtain the lower porous plastics of density as expected because of its molecular weight and viscosity are lower.

In the method that is used for preparing powder blend, ethylene chloride base resin also can contain the water of the 50 weight % nearly form of slurry, high-concentration suspension liquid or moist block (for example with).According to the invention provides the method for removing these excessive waters.

There is thermo-stabilizer in the composition of the present invention, to allow with minimum degraded in high temperature process fused ethylene chloride base resin, particularly PVC.The suitable thermo-stabilizer of composition is comprised all thermo-stabilizers of knowing in the PVC field, comprise metallic soap, epoxidized oil, phosphorous acid alkyl and aryl ester, hindered phenol (containing metal soap), organo-tin mercaptide and organotin mercaptide ester, polyvalent alcohol, mixed metal stabilizer (for example Zn/Cd) and alkali formula lead stabilizer.Can obtain organotin stabilizer from commerce, comprising methyl-tin, butyl tin, tin octylate and ester group class tin.Various organic tin derivates comprise that sulfide, oxide compound, carboxylate salt (salt of lipid acid and toxilic acid), unsubstituted thiolate, sulfydryl acid esters, sulfydryl alcohol ester and mercaptan carboxylic acid's salt are known.Many tinbase thermo-stabilizers can trade(brand)name ADVASTAB available from Rohm ﹠ Haas Corp, Philadelphia, Pennsyivania." plastics additive and the properties-correcting agent handbook " can edit at J.Edenbaum, Van Nostrand Rein shown, 1992, the 17-20 chapter finds the more detail file of relevant thermo-stabilizer.

The proper lubrication agent that is used for processing PVC/WF blend among the present invention comprises those lubricants that are applicable to PVC, comprises " interior " and " outward " lubricant, also comprises classifying as having interior lubricated and outer those lubricants of lubricity equilibrated.Suitable internal lubricant comprises direactive glyceride, Stearyl alcohol, stearic acid, the fatty acid amide as ethylenebisstearamide (promptly two C16-C18 alkyl covalent linkage are connected on the polarity amide group of center), soap class and as the stearate of calcium stearate.Suitable external lubricant comprises long-chain montanic acid (being that long-chain C28-C32 alkyl covalent linkage is connected on the polar group, as carboxylic acid), contain the paraffin and the hydro carbons of short-chain branch alkyl, contain the long linear hydrocarbon n-paraffin, contain polyethylene wax with the very long straight chain hydrocarbon of some side chains.In can providing lubricated and outer lubricated between the agent of equilibrated proper lubrication comprise with the partly-hydrolysed synthetic fatty acid of calcium and long-chain brown coal ester type (as Wax OP and Wax E, can be, Mountainside, the New Jersey obtains) from U.S. Hoechst company.Can be at McMurrer, the summary that M.C. edits " is used for the PVC lubricant " now, " plastics are compound ", 7/8 month nineteen eighty-two, the 74-99 page or leaf finds the further information of the lubricant of relevant PVC.

Being applicable to that polymer processing aid of the present invention comprises contains aromatic vinyl, (methyl) vinyl cyanide and/or (methyl) alkyl-acrylates polymer of monomers and multipolymer, its molecular weight is greater than 50,000 gram/mole, be preferably greater than 500,000 gram/mole, most preferably greater than 5,000,000 gram/mole.The multipolymer that preferably contains a large amount of methyl methacrylates (" MMA ") and a small amount of alkyl acrylate such as ethyl propenoate, butyl acrylate or 2-ethylhexyl acrylate.Among the present invention, nuclear-shell-type processing aid that the function of external lubricant function and processing aid is combined also can be used as polymer processing aid.These " lubricated-processing aid " provide the typical process performance of processing aids acrylic resin, and having the additional advantage of external lubricant function, it flows and operation hours to bonding improvement of the hot metal surface of processing units by remarkable reduction fusion ethylene chloride base resin.The commodity polymer processing aid can trade(brand)name PARALOID available from Rohm ﹠ Haas Corp, Philadelphia, PA.

Be applicable to that cellulosic materials of the present invention generally comes from the timber source, as xylon, wood sawdust, wood powder, paper, reuse paper, cloth board, paper packing material, exsiccant plant, paddy skin, fruit stone shell etc.Other suitable cellulosic materials also comprises natural fiber, as hemp, sisal hemp, jute, cotton etc.Because the source of xylon is abundant and suitability, xylon can come from cork or hardwood.Compare with cork, hardwood generally provides short fiber, and flowing property powder blend preferably generally is provided.Ideally, the cellulosic materials particle should generally have little aspect ratio, to provide the flow of powder performance good admixture of powder composition.Generally, cellulosic materials provides these pellets, as cutting, mill, threshing, pyrolysis, chopping off, smash to pieces, peel off, frosted, sawed-off, engraving, etching, scrap etc. by being implemented mechanical workout.The aspect ratio of cellulosic materials can be 1-100, preferred 2-10.If aspect ratio is too high, cellulose particulates tends to reduce the flowable and the extrudability of powder blend so.If aspect ratio is less than about 2, the tensile strength and the rigidity of the matrix material that makes with admixture of powder composition of the present invention have some losses so.The cellulosic materials that generally has little aspect ratio is a wood powder, optimizes the wood powder from hardwood especially.Suitable wood powder particle diameter in 10-200 purpose scope, preferred 20-80 order.Though wood powder is the main source of fiber among the present invention, other fibrous a large amount of second sources or reclaimed fibre source come from comprises bamboo, rice, sugarcane bar and the fiber that reclaims from newspaper, carton, computer printed matter etc.

The cellulosic materials that is under the envrionment conditions typically absorbs water (the wet branch).For example wood powder generally contains the wet branch of about 7 weight %.Because the wet branch of CVR/CM material is generally to its physicals harmful (for example tensile strength reduction), so generally wish the water content of CVR/CM material is minimized.Although optimum fiber quality component contains the moisture that is less than 7 weight %, the method for preparing powder blend of the present invention is not subjected to the restriction of cellulosic materials water capacity.

For example also can use in the present invention and contain the nearly wood powder of 15 weight % moisture.Extrudable free flowing powder blend composition in the second aspect present invention contains at least a polyvinyl chloride resin of 40-55 weight %; 0.5-1.5 at least a thermo-stabilizer of weight %; 1.5-3 at least a lubricant of weight %; At least a polymer processing aid of 5-10 weight %; At least a wood powder of 34-52 weight %; At least a mineral filler of 3-15 weight %; At least a whipping agent of 3 weight % at the most.

The polyvinyl chloride resin, thermo-stabilizer, lubricant, polymer processing aid and the wood powder that are applicable to second aspect present invention have more than been described.

Be applicable to that mineral filler of the present invention comprises Calucium Silicate powder, zinc oxide, barium sulfate, calcium sulfate, Magnesium Silicate q-agent, diatomite, talcum, pure aluminium silicate, various clay and metal oxide.Preferred lime carbonate.Envisioning other mineral filler known in the art also provides the free flowing powder performance of powder blend of the present invention.Often use mineral filler reducing cost among the PVC, and be different from the cellulosic materials that is regarded as non-mineral filler.

Mix filler and not only can reduce the cost of CVR/CM powder blend, and be used to make the goods that make by powder blend opaque.Mineral filler has also reduced expansion and the shrinkage coefficient by the goods of CVR/CM powder blend preparation of the present invention.But the mineral filler of using excessive concentrations has reduced CVR/CM foaming or many physicalies of foaming product not.Find to add modulus in flexure or the rigidity that mineral filler not only can improve goods prepared in accordance with the present invention, and mineral filler has improved the flow of powder performance.The modulus in flexure that improves is expected to be used for the purposes that do not foam, the macropore pipe of anti-sag in for example using in the open air.The same with most of mineral filler, for lime carbonate, the particle diameter normal root of fighting to the finish is important according to the carrier performance in the goods of second aspect present invention preparation.If the median size of mineral filler (" PS ") is greater than about 100 microns, the extruded product surface will be tended to coarse so.The PS value also can reduce the shock strength with the goods of CVR/CM admixture of powder preparation of compositions of the present invention, particularly when higher consumption unfriendly greater than about 5 microns.If the median size of mineral filler is less than about 0.1 micron, powder is very many dirt so, thereby is difficult to processing.The mean P S of preferred mineral filler is about 0.5-2.0 micron.Amount of filler in 3-15 weight % scope, preferred 5-10 weight %.Mineral filler is influential slightly to the processing of CVR/CM composition.Be generally the spheric filler grain and tend to the composition that provides such, the composition that good fluidity makes in the filler grain by the shape irregularity during its fusion.Filler grinds through slight, produces rubbing effect, and this helps to remove the lip-deep settling of processing units (i.e. " anti-incrustation ").The consumption of mineral filler is too high also harmful, because they will cause the wearing and tearing that caused processing units by grinding.For this effect is minimized, should avoid using coarse stuff.

Being used for various CaCO3 filler of the present invention can be available from Omya company, Proctor, and the vermont, its particle diameter is as follows:

Rank median size (micron)

Ultra-Pflex　　　　?0．07

Omyacarb?UFT　　　 0．7

Omyacarb?1T 　　　?1．0

Omyacarb?2T 2．0

Omyacarb?3T 3．0

Omyacarb UFT filler is particularly useful in comprising as the PVC of vinyl chloride resin and the composition as the WF of cellulosic materials.

Although most of mineral fillers are white or linen, it should not obscured with the real pigment that can choose adding CVR/CM powder blend wantonly.The optional filler that is used for painted PVC plastics is well known in the art, comprises as the mineral base pigment of titanium dioxide (white) with as the organic radical pigment of phthalocyanine (blueness).Those skilled in the art can select other tinting material, as are used to control the dyestuff and the light agent of CVR/CM goods color.The total amount of used optional colorants can be the 3 weight % at the most of CVR/CM admixture of powder total composition.In this case, the total amount of tinting material and mineral filler will remain between the 3-15 weight %.

Powder blend of the present invention can further be chosen wantonly and comprise at least a whipping agent with preparation CVR/CM foaming product.The consumption of whipping agent or ratio will change according to the type and the matrix material desired properties of whipping agent.Powder blend of the present invention can further be chosen wantonly and comprise at the most 5 weight %, preferred 0.2-5 weight %, at least a whipping agent of 0.2-3 weight % most preferably, with preparation CVR/CM foaming product.

Can use and be used to prepare any suitable whipping agent of other component compatibility of CVR/CM porous plastics.Whipping agent mainly contains two types: physics with chemistry.It is volatile liquid or the pressurized gas that undergoes phase transition when being processed to form foam structure that pneumatogen tends to.It is the solid that the energy thermolysis produces gaseous decomposition product that chemical foaming agent tends to.The gas that produces disperses well so that foam structure to be provided in thermoplastic melt.Preferred one or more whipping agents comprise chemical foaming agent.

Chemical foaming agent can be further divided into organic and inorganic.Organic blowing agent can be used for different chemical, physical form and the modification of wide region, as azodicarbonamide.Inorganic foaming agent is then more restricted.Typical inorganic foaming agent is made up of sodium bicarbonate and citric acid, and it produces carbonic acid gas when decomposing.Chemical foaming agent provides with powdery or pellet form usually.The concrete selection of whipping agent will be referred to cost, desired abscess development and gas yield and desired performance of composites.

Preferred chemical foaming agent provides with powder among the present invention, and is mixed in the CVR/CM powder blend, to be provided for reducing the CVR/CM porous plastics and the heat insulation or sound-proofing properties of raising of density or hardness.Form the cavity by acting in the matrix of chemical foaming agent in the processing or abscess improves the CVR/CM foaming composition.Whipping agent discharges gas formation abscess by the suitable moment of work in-process.

In addition, perviousness and the volume of per unit weight whipping agent discharge gas of foaming agent gas in polymkeric substance is the important factor of selecting whipping agent.These factors are called foaming or whipping agent efficient.Effectively whipping agent should produce 100-200 milliliter gas/gram whipping agent at least under standard temperature and pressure (STP).According to foaming degree, i.e. the volume fraction of the foaming matrix that constitutes by the cavity, these the finished product performance of composites may significantly be different from solid or matrix CVR/CM material.

The wide range of commercial chemistry whipping agent.But the preferred particle diameter little powder compatible with lubricant.This area has been known can be by being present in the activation that stearic acid in one or more lubricants improves and improve whipping agent.Also can assist its dispersion in the dry powder blend to the wetting action and the preceding coating of processing of polymkeric substance by lubricant by whipping agent improvement polymer particle.

Suitable inorganic chemistry whipping agent comprises sodium bicarbonate and citric acid.Suitable organic chemistry whipping agent has non-activated decomposition temperature in the work range of CVR/CM mixture.Suitable organic chemistry whipping agent and non-activated decomposition temperature thereof comprise p-toluene sulfonyl hydrazide (" TSH ": 120 ℃), right, right-oxo two (benzol sulfohydrazide) (" OBSH ": 165 ℃), azodicarbonamide (" AZO ": 195-210 ℃), dinitrosopentamethylene tetramine (" DNPT ": 200 ℃), p-toluene sulfonyl hydrazide Urea,amino-(" TSSC ": 235 ℃) and 5-phenyltetrazole (245 ℃).Many organic chemistry whipping agents can be available from Hughes industry (Kennesaw, Georgia) and Uniroyal chemical company.AZO and sodium bicarbonate are the preferred whipping agents that uses.Also wish to be used in combination one or more whipping agents, comprise one or more organic chemistry whipping agents (being AZO) and inorganic chemistry whipping agent (being sodium bicarbonate).

Whipping agent also can be used in combination with abscess control agent (foaming stabilizer), the abscess control agent generally be comprise in the admixture of powder composition have surface-active reagent (tensio-active agent).These tensio-active agents help the mixing in stable foam, control abscess-size, the assist gas (air) and eliminate over-blowing.These tensio-active agents can be available from aviation goods company, Allentown, Pennsyivania and Dow Chemical, Midland, Michigan State.

Also can choose wantonly in the powder composition of the present invention and comprise the impact modifier that is used for the modification plastic resin known in the art, the CVR/CM mixture that improves with preparation toughness.The 15 weight % at the most of total composition may optionally be one or more impact modifiers, preferably 10 weight % at the most.Can buy suitable impact modifier known in the art, comprise " multistage " or " nuclear/shell " polymer particle of knowing, its substantially by methyl acrylate, vinylbenzene and divinyl (for example " MBS ") resin, further contain acrylonitrile monemer MBS (for example " MABS "), prepare based on acrylic ester impact-resisting modifier (as AIM) and acrylic polymer (as polymethylmethacrylate), the chlorinatedpolyethylene (" CPE ") of esters of acrylic acid rubber (as polyalkyl acrylate) and the polymkeric substance that contains silicone rubber.Can obtain various MBS and AIM impact modifier from Rohm ﹠ Haas Corp, Philadelphia, Pennsyivania.

At last, admixture of powder composition of the present invention can be chosen wantonly and comprise other component commonly used in the matrix resin blend.These comprise softening agent (as dioctyl phthalate (DOP) etc.), ultra-violet stabilizer, toner, rheology modifier, fire retardant, press down fumicants, static inhibitor, flatting agent, anti-hard caking agent, antioxidant, releasing agent and hollow ball.It can be added with emulsion, liquid or powder type, its consumption is well known in the art, searches in " plastics additive and the properties-correcting agent handbook " for example can edit at J.Edenbaum in 1992, Van Nostrand Rein shown.

The method of CVR/CM powder produced according to the present invention further allows to introduce the aqueous-based dispersions of various components, can be water so that add the nearly 25 weight % of component total amount in this process.The component that provides with aqueous-based dispersions comprises polymer processing aid, optional impact modifier, thermo-stabilizer, CVR, CM, filler, lubricant, pigment etc.Preferably the component that provides with aqueous-based dispersions comprises polymer processing aid and optional impact modifier, because they are typically to prepare with aqueous-based dispersions by emulsion polymerization technology.

Polymer processing aid and impact modifier generally make with emulsion form, are separated into powder then, as passing through cohesion or spraying drying.Extra time that these separating steps need be used to process and fund, and often cause the loss of product output.The component of emulsion form rather than powder type is carried out blend and processing has superiority most, because some emulsion is difficult to be separated into powder or separation costs is too high.Typically, these components contain the water of 30-80 weight % when making emulsion, but these water the method according to this invention are removed fully.The equipment that is used for admixture of powder processing comprises blending machine, forcing machine or the kneader that can remove the branch that dries from powder blend.

The aqueous-based dispersions of adding polymer processing aid and/or impact modifier provides and these components has been added fashionable equal result with powder type, and wherein the consumption of other component and preparation method are as mentioned above.The preferred thermodynamics blending machine that uses is to remove the branch that dries from these blends.Typically can remove the wet branch of 80-90%, and powder property (as leakage current and fluff packing density) is had no adverse effect.Suitable device can obtain from U.S. Henschel mixer company (Huston, Tennessee State).Introduce specific components with aqueous-based dispersions the mixture blend powders can be provided, it is similar to the mixture blend powders that the same composition that adds in order to powder type obtains.Similarly, these aqueous-based dispersions that add according to the inventive method provide desired low foam density and good extrusion performance (be that tractive force and output speed are satisfactory, and can the observations when adding component with powder type compare).

The blend method of various components (for example CVR, CM, thermo-stabilizer, lubricant, polymer processing aid, mineral filler, whipping agent and optional impact modifier etc.) generally comprises the various components of blend in suitable device, blend mixed and be heated at least 50 ℃, preferably be higher than 80 ℃ and most preferably be higher than 100 ℃, and the water capacity of final powdery blend is reduced to is lower than 3 weight %, preferably is lower than 2 weight % and most preferably be lower than 1 weight %.Although this method generally is designed to reduce wet the branch, as fruit component be exsiccant or before blend through predrying, just need be in blend except that the step of the branch that dries.The various orders of adding, heat and mixing various components are enough to prepare the admixture of powder composition that can extrude and can provide the slick foaming and the extrudate that do not foam.

Preferred ingredients blend order (i.e. " blend circulation ") is, be warming up to more than 70 ℃, preferred more than 85 ℃ after and in CVR and optional foaming agent the adding thermo-stabilizer add CM afterwards, form first blend.Preferably thermo-stabilizer is mixed in first blend with CVR, preferentially absorbed with the assurance thermo-stabilizer, and less absorbed by CM by CVR, can its validity of reduction because absorbed by CM.Then can be under the envrionment temperature of blending machine the CVR of preconditioning be added with CM.Subsequently lubricant, polymer processing aid and mineral filler are added, mix and heating.Discharge wet the branch to reduce water capacity.Compare with the similar approach that adds CM in blend loop start or terminal point, this method provides minimum residual powder water capacity and minimum foam densities (when using optional foaming agent).

Adding the CM that contains CVR and optionally foam agent at the blend loop start also is acceptable component blend order.This method typically provides fluff packing density the high and fast powder blend of leakage current flow rate.The gained powder is easy to extrude, and provides and almost equal extrusion pressure, output speed and the extrudate quality of above-mentioned preferred ingredient blend order gained powder.Not too wish to add CM at blend circulation terminal point, because of it causes the long blend time, this is because reduced the blend temperature when adding CM and must heat once more to discharge wet the branch.Generally like this provide wet minute higher level, reduced the quality of powder property.This causes higher extrusion pressure, higher power input and the higher foaming extrudate density extruded.

When adding various component in this process, the interpolation total amount of preferably water is less than or equal to 25 weight %, preferably less than 15 weight %, most preferably less than 10 weight %.When adding various component with aqueous-based dispersions, also the interpolation total amount of preferably water is less than or equal to 25 weight %, preferably less than 15 weight %, most preferably less than 10 weight %.When adding the aqueous-based dispersions of one or more components, preferred one or more components (as whipping agent) that influenced by water that add subsequently are lower than 3 weight % so that the water capacity of mixture is reduced to, and preferably are lower than 2 weight %, most preferably are lower than 1 weight %.

Preferably rise to more than 60 ℃, preferably add lubricant after more than 80 ℃ adding CM and temperature.Preferably after lubricant, add polymer processing aid.For the powder of good flowing properties is provided, the preferably optional mineral filler of blend after lubricant and polymer processing aid.

Also may be before adding other component, at first the aqueous dispersions with water base component such as polymer processing aid mixes with CM, removes subsequently or simultaneously and anhydrates.

Those skilled in the art have known to use to be designed for removed the nearly equipment of 25 weight % water from the compositions that contains polymkeric substance.For example with standard equipment with component with powdery or the blend of aqueous solution form, as high-speed mixer, blending machine, kneader, forcing machine and/or fluidizing drying bed.The various components (for example lubricant, thermo-stabilizer, wax, pigment and filler) that the typical case adds in vinyl chloride resin prescription also can add in the same mixing equipment-with aqueous solution form, liquid form or powder type.In this blend, the water that adds with component will be evaporated, and become a part that blend is heated to the target temperature process.Preferred mixing equipment possesses the means (as vacuum or exhaust) that the water vapour that may generate in the blend operation is removed.

Preparing the step that the method for the extrudate that foams generally comprises is, the extrudable free flowing powder blend that will contain at least a whipping agent adds in the forcing machine, the melted powder blend to be to form melt in forcing machine, with melt from the mouth mould, extrude with formation have the foaming extrudate at least one surface and with the surface of cooling fluid sclerosis foaming extrudate to improve the expansion ratio of foaming extrudate.This extrudate can have any extrudable shape, comprises bar-shaped, sheet material, tubing, hollow or solid special material, film etc., but is not limited to this.

That the those of skill in the art of polymer processing field know is reinforced, the step of fusion, formation and melt extrusion.Typically use forcing machine with feeding section and metering zone.Can in " polymer processing principle " that Z.Tadmor in 1979 and C.G.Gogos, John Wiley are shown, find more detailed data.

Be easy to finish with cooling fluid sclerosis foaming extrudate surface by the suitable conveying equipment for fluid substances that cooling fluid is pointed to foaming extrudate surface.When cooling fluid was gas, the preferably fluid handling equipment was one or more " air knives ", but the anticipation miscellaneous equipment also is easy to the gas sensing is needed refrigerative surface, for example air curtain, scraper, fan, diffuser, vortex water cooler etc.

When extrudate is sheet, the top and the bottom of the sheet extrudate that leaves mouthful mould surface are all cooled off.Carry out this cooling by one or more air knives being orientated towards extruding direction.Valving by the controlled chilling air velocity is supplied pressurized air to air knife.Preferred air knife points to the extrudate that the direction of leaving mouthful mould is come out from the mouth mould with cooling, and the direction that carries over the extrudate section is to avoid cooling vent mould surface.Air knife is placed in the top and lower surface 0.5-20 cm range apart from the extrudate surface preferred 2-8 centimetre.

Preferred cooling fluid contact is near the foaming extrudate of extrudate from the position that the mouth mould comes out.If the cooling fluid contact is away from the foaming extrudate of mouth mould outlet, expansible gas (coming from whipping agent) will have an opportunity to escape before surface hardening so; In this case, the expansion ratio of the porous plastics fluid that is not cooled amplifies.Foaming extrudate in the preferred cooling fluid contact distance mouthful mould outlet 1-20 cm range.Also preferred cooling fluid points to the extrudate surface, so that cooling fluid contact opening mould not, thereby avoid the cooling vent mould.The temperature on maintenance mouthful mould surface helps to keep the good slick outward appearance on extrudate surface and marginal laceration is minimized.

Preferred used cooling fluid is an air, but also can use other gas, as rare gas element (as nitrogen, argon gas, helium), fluorochlorohydrocarbon and carbonic acid gas.Also can with the liquid cooled fluid for example water point to foaming extrudate surface, but this does not more expect, because will be more loaded down with trivial details than handling gas to the collection and treatment subsequently of liquid.Can wish to use deacration cooling fluid in addition, wherein cooling fluid also can be brought into play its function, as cleaning or processing extrudate surface.

In this section the cause of using cooling fluid can increase this phenomenon of expansion of foaming extrudate has been proposed possible explanation, but this will can not limit the scope of the invention.Be limited to theory although forbid to enjoy, the present inventor thinks that the effect of cooling air is to allow extrudate " epidermis " more promptly to solidify and prevent to form the escape of gas of abscess.In the nuclear of the cooling surface of extrudate (as sheet material), the abscess prolonged expansion is until reach balance between abscess air pressure and extrudate viscosity.Expansion ratio is the ratio of thickness of the thickness counterpart mould exit sheet material of final chilled foam sheet.In this, can obtain maximum ga(u)ge, and not be subjected to the influence of the traction that pulling-on piece speed causes.The cooling that does not have cooling fluid to provide, maximum sheet thickness are limited by the tensile of downstream discharge rate can.Cooling comprises product size (bigger expansion ratio) and the lower overall consistency that significantly thickens to the benefit of physicals.Can be subsequently chilled foaming extrudate processing (as embossing, compacting, molding, car, brill, thermoforming, cutting etc.) be become goods (for example material of construction, as window profiled material and plate washer).

After air knife, also can use one group through the contact surface of heating and cooling to repeat fusion and cooling sheet material " epidermis ", provide very hard, smooth and have the outward appearance of aesthetic.For example, the chromium roller of available differing temps changes foaming extrudate surface after surface hardening.In addition, hot pressing and colding pressing can be used for changing outward appearance, surface hardness and the density of the cutting product of foaming extrudate sheet material.

Mixture of the present invention contains the base layer made by extrudable thermoplastic resin and at least one stratification tread band of being made by extrudable free flowing powder blend composition of the present invention thereon.

Can extrude compound and use these layers to prepare mixture of the present invention together by extruding multi-layer thermoplastic with ad hoc fashion.It will be according to of the present invention first or the tread rubber composition of second aspect that at least a thermoplasticity is extruded compound, and place as another thermoplasticity at least of one deck base layer at least and extrude on the compound.Also anticipation can be extruded into the tread rubber composition multilayer to allow one or more surfaces Additional Protection of mixture.

Typical tread rubber can be the 0.1-1.0 mm thick, and the structural plastic matrix can be about 0.8-1.8 mm thick when being used for the PVC plate washer, can be the 1.2-3.0 mm thick when being used for PVC profiled material (for example PVC window frame, grille, cover plate and awning).If tread rubber and matrix are blocked up, goods cost so prepared therefrom is too high, if but thin excessively, it will lack intensity so.

Also can form base layer by extruding thermoplastic resins.But thermoplastic resin can be any extruding thermoplastic resins known in the art, and its example is described in U.S. Patent No. 5,318,737, but disclosed extrusion resin and extrusion method are incorporated herein by reference.Matrix can be foamed, but preferably not foam, to give mixture with rigidity.

But be particularly suitable for making material of construction but comprise PVC, chlorinated polyvinyl chloride (" CPVC "), high-impact polystyrene (" HIPS "), polypropylene (" PP ") and acrylonitrile-butadiene-styrene (ABS) (" ABS ") by the preferred extruding thermoplastic resins that the tread band that CVR/CM composition of the present invention makes is improved outward appearance.But the extruding thermoplastic resins of also preferred tread band and base layer is bonding to prevent the delamination of mixture mutually.Can by select can be compatible and/or miscible mutually resin and composition (as PVC/WF composition of the present invention and PVC coextrusion) improve bonding.Expection can adopt the whole bag of tricks known in the art to improve bonding between the matrix of mixture and the tread band, as carry out surface treatment (being corona discharge) and/or use tackiness agent with bonding improving agent.

But mixture of the present invention contains the base layer of extruding thermoplastic resins and the tread band of middle tread rubber composition according to a first aspect of the invention placed on it.Preferably prepare mixture by coextrusion, but also can be by heat fusing or gluing preformed sheet or frlml laminating formation mixture with matrix and tread rubber.

But the preferred extruding thermoplastic resins as base layer in the mixture of the present invention comprises PVC, CPVC, high-impact polystyrene (HIPS), polypropylene (PP) and acrylonitrile-butadiene-styrene resin (ABS) and styrene-acrylonitrile resin (SAN).Preferred tread band is according to PVC/WF blend of the present invention, it contains at least a polyvinyl chloride resin of 40-55 weight %, 0.5-1.5 at least a thermo-stabilizer of weight %, 1.5-3 at least a lubricant of weight %, at least a polymer processing aid of 5-10 weight %, at least a wood powder of 34-52 weight %, at least a mineral filler of 3-15 weight % and at least a whipping agent of 3 weight % at the most.

Also can use standard thermoforming process known in the art subsequently goods of the present invention, sheet extrudate and mixture to be thermoformed into difform goods.

Also can adopt standard staining technique known in the art subsequently with goods of the present invention, sheet extrudate and mixture and thermoformed articles dyes or coating.

Embodiment

The universal method of preparation CVR/CM powder blend-whole components are essentially dry powder

Having developed provides thorough mixing and does not need any additional processing step just can remove the blend flow process (as described below) of the branch that dries.This method permission adding water capacity is about at the most 7% cellulosic materials (as wood powder), and this water capacity that causes the admixture of powder composition is less than about 0.5%.According to this blend order, wherein after adding CVR and CM but before adding the polymer processing aid powder, add lubricant, can reduce the floating dust amount, and compare when adding lubricant after the polymer processing aid powder, this blend mixes more evenly.

The CVR resin is placed Henschel high speed blending machine.With spatula with the optional foaming agent manual mixing in the CVR resin.Blending machine stirs with low speed and begins also (choosing wantonly) heating.When reaching about 50 ℃, temperature adds thermo-stabilizer.Improve the stirring velocity of blending machine subsequently.When temperature reaches about 90 ℃, stop blending machine and stir, add CM this moment.After adding CM, temperature will be reduced to about 50 ℃, begin blending machine once more with low speed this moment and stir.Open the window that blending machine covers.Make the blending machine exhaust with exhaust ventilation pipe, to drain the water vapour of any escape near the window of opening.Progressively add lubricant, and make powder blend reach about 100 ℃.When removing water vapour, keep this temperature.When the wet branch of major part had been removed, temperature began to rise.At this moment, progressively add polymer processing aid and optional impact modifier, progressively add optional pigment and filler then.With powder blend be heated to about 110 ℃ to guarantee that water capacity is less than about 0.5 weight %.This powder blend is cooled to the temperature (being lower than about 65 ℃) that is enough to safety processing, and carries to suitable extrusion equipment.

In the blend process, wish to detect powder blend to obtain good mixing vortex by speed and/or the deflection blade (if feasible) of regulating blending machine.It should be noted that the general rapid cooling of the higher blend of CM content, and may need outer heating.At last, optional foaming agent is mainly used in preparation abscess (foaming) composition.When the admixture of powder composition that preparation is not foamed, do not use whipping agent.

Component source and general description that table 1 uses in an embodiment

Be used to prepare the general description of extruding of the powder composition of extrudate

Because cellulosic materials (as wood powder) is good insulation agent, so adopt typical extrusion temperature pattern (the metering zone temperature that promptly raises is to being higher than the feeding section temperature) to be difficult to discharge vacuum and in the powder of not expecting to remove, remove remaining wet branch.When adopting opposite temperature model (promptly at feeding section top temperature is arranged, and lower the temperature gradually to metering zone), vacuum available is removed the branch that dries, and does not produce powder at exhaust gas region.So with plastic working KMDL forcing machine is sheet material with the powder extrusion moulding under the following conditions: machine barrel district 1 (" BZ1 ")/machine barrel district 2 (" BZ2 ")/mouth mould (" D ")/screw rod cooling coil=185/180/185/170 ℃.

Reference example 1 and embodiment 2

Following embodiment has shown that the lubricant system of the PVC/WF powder of the mixture that is used for foaming must be adjusted to by weight percentage and its being on close level in the PVC prescription, with the processing characteristics that proves that it is good.With comparing that prior art is instructed, this makes the quality of processing and product obtain remarkable improvement aspect surface quality and the edge quality.Provided the outward appearance of extrudate in the following table 2.

Table 2

Comparative example 1-5 and embodiment 6-8

Change the influence of lubricant and polymer processing aid total amount

When following comparative example 1-5 and embodiment 6-8 show that overall weight percent when lubricant and polymer processing aid is respectively greater than about 1.5 weight % and 3.5 weight %, surperficial and entire high quality extrudate have been obtained.With plastic working KMDL forcing machine is sheet material with the powder extrusion moulding under the following conditions: (BZ1/BZ2/D/ screw rod cooling coil=185/180/185/170 ℃).Provided the outward appearance of contrast extrudate in the following table 3.

The result of these paired observations is shown that comparative example 1 surface and edge quality are very coarse, and the consumption that further increases CaSt does not have influence (comparative example 2) to surface or edge quality.In addition, although increase paraffin and PE wax have improved surface quality, edge quality becomes poorer (comparative example 3).Comparative example 4 shows the total amount that increases paraffin, compare with comparative example 3 not have obviously and improve, but it obtains minimum extrudate density and the highest output speed.

Polymer processing aid is being useful aspect the good melt strength that keeps the CVR/CM composition.Shown in these embodiment, when improving the wood powder consumption and be used for processing PVC/wood powder mixture (shown in these embodiment) to have enough melt strengths, it is consumption in by weight percentage the standard PVC prescription at least that the overall weight percent of polymer processing aid should remain on.

These embodiment have shown and only improve the lubricant total amount or only improve the polymer processing aid insufficient total amount so that good melt flow and surface quality to be provided.Need increase both simultaneously so that the excellent balance of processing characteristics to be provided.

Table 3 changes the influence of lubricant and polymer processing aid total amount

Embodiment 9-12

In the relative total amount that keeps lubricant and polymer processing aid, improve the influence of cellulosic materials consumption

Overall weight percent by keeping lubricant and polymer processing aid is respectively greater than 1.8% and 5.6%, can obtain to contain the nearly CVR/CM admixture of powder composition of 42.90% (100phr) cellulosic materials (being wood powder herein), it can provide surface and entire high quality extrudate.With plastic working KMDL forcing machine is sheet material with the powder extrusion moulding under the following conditions: (BZ1/BZ2/D/ screw rod cooling coil=185/180/185/170 ℃).Provided the outward appearance of gained extrudate in the following table 4.All these composition processing are good, and with the raising by embodiment 9 to embodiment 12 wood powder percentage ratios, surface flatness has improved.From embodiment 9 to embodiment 12, output speed reduces, and this is owing to the higher tap density of powder blend that causes of percentage composition of the lower wood powder of density is lower.

Table 4: the influence that improves the cellulosic materials consumption

Embodiment 13-16

Change the influence of vinyl chloride resin molecular weight

Overall weight percent by keeping lubricant and polymer processing aid is respectively greater than 1.8% and 5.6%, can obtain to contain the ethylene chloride base resin of various molecular weight (being the PVC of K50, K57, K62 and K67 herein) and the CVR/CM admixture of powder composition of about 38% (80phr) cellulosic materials (being wood powder herein), it can provide surface and entire high quality extrudate.With plastic working KMDL forcing machine is sheet material with the powder extrusion moulding under the following conditions: (BZ1/BZ2/D/ screw rod cooling coil=185/180/185/170 ℃).Provided the outward appearance of gained extrudate in the following table 5.The processing of all these compositions is good, and is increased to the K67 of embodiment 13 with the molecular weight of PVC from the K50 of embodiment 16, and surface flatness is improved.Be reduced to the K50 of embodiment 16 with extrudate density from the K67 of embodiment 13, output speed raises.On the basis of these embodiment, it seems that K50 PVC (lowest molecular weight in the experiment) is suitable for preparation foaming extrudate most: its processing is good, and provides density minimum extrudate porous plastics.

Table 5: change the influence of vinyl chloride resin molecular weight

Embodiment 17 and 18

Change the influence of whipping agent and porous plastics type

Overall weight percent by keeping lubricant and polymer processing aid can make the CRV/CM admixture of powder composition that contains the different whipping agents that are useful on dissimilar porous plastics respectively greater than 1.8% and 5.6%.Nearly the cellulosic materials of 38% (80phr) (being wood powder herein) can be used for preparation surface and entire high quality extrudate.With 25 millimeters Krauss-Maffei of conical double-screw (Austria) plastic working KMDL forcing machine is sheet material with the powder extrusion moulding under the following conditions: (BZ1/BZ2/D/ screw rod cooling coil=185/180/185/170 ℃).Provide the outward appearance of gained foaming extrudate in the following table 6.

Table 6: change the CVR/CM foaming formulation

In (abscess) PVC/ of these foaming wood powder mixture,, can obtain lower density when the foaming agent consumption that raises by weight percentage produces total amount when constant to keep gas with gross weight.Compare with AZO (azodicarbonamide), the sodium bicarbonate whipping agent shows the density that can provide lower.It is good that two kinds of compositions are all processed, and its surface and edge quality are good.Embodiment 18 also comprises white pigment (TiO2).

Embodiment 19

Use filler so that free flowing powder to be provided

Adding wood powder generally can reduce tap density and reduce flow of powder.Adding CaCO3 can improve tap density and improve flow of powder to the degree that can directly extrude the PVC/WF blend from powder blend.For example, the mixture of being made up of the foaming powder composition of the PVC of the wood powder of 50 weight % and 50 weight % (as PVC, thermo-stabilizer, whipping agent, lubricant, polymer processing aid and be less than about 1.5% filler) can prepare according to above-mentioned universal method.The powder accumulation density of this PVC/WF admixture of powder composition is 0.342 grams per milliliter, but tests according to the leakage current of ASTM D 1895-96, and it does not flow.With making the weight ratio of PVC foaming compound/wood powder/CaCO3 blend in the described just now admixture of powder composition of mineral filler (lime carbonate) adding is 48/48/4.The powder blend of gained is a free flowing powder, and it has 30 seconds the good leakage current flow rate and the tap density of 0.363 grams per milliliter.

Embodiment 20-22

The method for preparing the CVR/CM powder blend of at least a component is provided with aqueous-based dispersions

At least a component of following examples proof admixture of powder composition can provide by aqueous-based dispersions.Except that add after removing most of extra water through heating and exhaust any component (as optional foaming agent) to water sensitive with wet minute of the residue that is less than about 3 weight %, it is substantially the same with aforesaid method to prepare CVR/CM admixture of powder method for compositions.Can use thermodynamics blending machine (for example Henschel or Papenmeier blending machine) the described operation of employing table 7 of band cooling jacket to prepare the powder blend among the following embodiment 20-22.For adding optional foaming agent each step before, the blending machine exhaust is evaporated to allow most of moisture, so that the wet minute total amount that keeps is lower than about 3 weight %.Required total time of whole process is about 30 minutes.

The universal method of CVR/CM composition among the table 7 preparation embodiment 20 to 22

The preparation of the aqueous-based dispersions of polymer processing aid (HPPA-W)

Mw is the letex polymerization of 6,000,000 (using gel permeation chromatography) and the processing aids acrylic resin be made up of 84% methyl methacrylate, 12% n-butyl acrylate and 4% n-BMA monomer.The 100 part monomers (total amount of butyl acrylate, methyl methacrylate and butyl methacrylate) of umber to be used to prepare.

In the suitable reactors that is equipped with condenser and temperature sensing means, add 79.679 parts of deionized waters.With nitrogen jet deionized water 30 minutes, be heated to 47 ℃, add 0.021 part of Glacial acetic acid, add 3.057 parts of solid contents then and be 45% aqueous emulsion polymers by 49% butyl acrylate, 49% methyl methacrylate and the preparation of 2% methacrylic acid.Then with 1.646 parts of commodity list surface-active agent Dowfax 2A1 available from Dow Chemical ^TMAdd in the same reactor.These add component with 2.7 parts of deionized water rinsings.The mixture for preparing 0.0061 part disodium EDTA dihydrate, 0.00052 part of ferric sulfate (II) salt heptahydrate and 0.245 part of deionized water respectively.This mixture is added in the reactor.With 2.7 parts of above-mentioned chargings of deionized water rinsing, nitrogen jet is become nitrogen purging.

Preparation is by 12 parts of butyl acrylates, 83.9 parts of methyl methacrylates and 4.0 parts of monomer mixtures that butyl methacrylate is formed in separation vessel.17.70 parts of these mixtures are added in the reactor.70% aqueous solution and 1 part of deionized water of in reaction mixture, adding 0.0038 part of sodium formaldehyde sulphoxylate, 0.0031 part of tertbutyl peroxide then.

After the heat release, mixture is cooled to 41 ℃, adds 22.75 parts of monomer mixtures then, add 70% aqueous solution and 1 part of deionized water of 0.0048 part of sodium formaldehyde sulphoxylate, 0.0040 part of tertbutyl peroxide subsequently.

After the heat release, mixture is cooled to 32 ℃, during cooling adds 2.301 parts of Dowfax2A1 and 1.2 parts of deionized waters.Add remaining 60.68 parts of monomer mixtures, add 70% aqueous solution and 3.4 parts of deionized waters of 0.023 part of sodium formaldehyde sulphoxylate, 0.027 part of tertbutyl peroxide subsequently.

After the heat release, add 0.1 part of butyl acrylate, add 70% aqueous solution and 4.6 parts of deionized waters of 0.0040 part of sodium formaldehyde sulphoxylate, 0.0024 part of tertbutyl peroxide subsequently.This mixture is cooled to 35 ℃, and final weight percent solids is 51.6%.

The preparation of powdery polymer processing aid (HPPA-P)

To form the powdery polymer processing aid, it is expressed as HPPA-P with a HPPA-W dispersion liquid spraying drying.

The preparation of the aqueous-based dispersions of impact modifier (IM-W)

By the aqueous-based dispersions of following universal method with emulsion preparation acrylate nucleoid/shell impact modifier (being expressed as IM-W), it consists of 80 n-butyl acrylates/20 methyl methacrylates.

In the suitable stirred reactor of the means that are equipped with the equipment, reflux exchanger and interpolation monomer and other component that feed nitrogen, add 49.3 parts of deionized waters and 0.021 part of Glacial acetic acid, in nitrogen jet, be heated to 45 ℃.Regulating nitrogen then makes it purge atmosphere on reaction mixture.The 0.100 part sodium formaldehyde sulphoxylate (SFS) of preparation in 2.33 parts of deionized waters, and with in its adding reactor.12.6 parts of esters of acrylic acid seed emulsion are added in the reactor.Emulsified monomer mixture (EMM) (containing 28% aqueous mixture of 1.43 parts of SLS, 21.8 parts of deionized waters, 78.2 parts of n-butyl acrylates and 0.867 part of Viscoat 295) with 0.699 part of deionized water rinsing 10%.Prepare 0.110 part of cumyl hydroperoxide (CHP) then.Add 11% of this CHP material then.The mixture heat release that induces reaction of added initiator.Add twice other EMM and CHP charging according to similar mode: forms by the EMM of above-mentioned add-on 20% and 18% CHP material for the second time, expect to form by 40% EMM and 39% CHP for the third time.For the 4th time and last interpolation of EMM, come the remaining 30%EMM of modification by adding 0.023 part of allyl methacrylate(AMA) before adding reactor at EMM.With 2.69 parts of deionized water rinsings.Add remaining 32%CHP then.

After the heat release, emulsion being cooled to 55 ℃, is to prepare in second step.After the cooling, add the 0.023 part of SFS, 20.9 parts of methyl methacrylates (MMA) and the 0.001 part of n-dodecyl mercaptan (n-DDM) that are dissolved in 1.13 parts of deionized waters.With 2.31 parts of deionized water rinsings.Add the 0.023 part of Sodium Persulfate (NaPS) that is dissolved in 1.13 parts of deionized waters then.With reactor cooling to 35 ℃.Filter polymer emulsion then.

Embodiment 20 to 22

The admixture of powder composition of the method preparation that provides with aqueous-based dispersions according to polymer processing aid in the table 7 and/or impact modifier has been described in table 8.

These embodiment are shown as preparation CVR/CM powder blend, can emulsion or powder type adding impact modifier and/or polymer processing aid.Embodiment 20 is reference examples, is used for more under equal conditions adding the result of polymer processing aid powder gained.Embodiment 21 proof polymer processing aids can emulsion add.

Surprisingly, add impact modifier and/or polymer processing aid some additional advantage of not expecting in wood powder-PVC blend are provided.In embodiment 22, add two kinds of components and can in blend, obtain providing in the higher water capacity (3.09%) of high fluff packing density (0.487 grams per milliliter) to(for) powder, powder blend leakage current value (12.1 seconds), high output speed (6.1 kilograms/hour are inferred because improved powder property) and the very low foaming product (0.59 grams per milliliter) of density fast.At last, although initial wet divides level higher, and must be in blend and extrusion step remove the branch (about 13.40%) that dries from adding emulsion mixture, edge and surface quality and extrusion performance are good.

The initial wet score value is with the wet score value (7.11%) of wood powder, the wet score value (for aqueous-based dispersions is 47%, is 0% for powder) of impact modifier and wet score value (for aqueous-based dispersions is 47%, is 0% for the powder) meter of polymer processing aid.Determine fluff packing density with the powder gram number that is full of 100 milliliters of graduated cylinders.According to ASTM D 1895-96, the flow velocity that leakage current flow rate detection powder flows through from standard funnel.By being dried to final wet branch that constant weight detects powder blend.

To become the foaming extrudate according to the powder processing that embodiment 20 to 22 prepares, reverse twin screw extruders, and use three-roller calendar in 35 rev/mins of operations with 35 millimeters KMDL that are furnished with 3 inches wide improvement Celuka sheet die.Charging is set and is equaled 6.0, only sets the gap with ejector pin, sets the quota vacuum in exhaust ports, and opens visor in a side.The temperature of screw/barrel #1/ machine barrel #2/ mouth mould is respectively 175 ℃/195 ℃/185 ℃/185 ℃).The performance of forcing machine and foaming quality of extrudate and density the results are shown in table 8.

In the variation of embodiment 22, wood powder adds as step 3 after adding thermo-stabilizer and before adding polymer processing aid.This causes the free flowing powder composition of low water capacity 1.35%.

Embodiment 23 to 27

The influence of component interpolation order in the admixture of powder

Be used for detected components interpolation order to gained powder and foaming extrudate Effect on Performance, compositions for use is listed in table 9 among the embodiment 23 to 27, and its component source is as shown in table 8.These powder blend are to prepare under the listed condition of table 10 and table 11 in 75 liters of Henschel mixers.

40 rev/mins of operations down,, every kind of powder processing is become the foaming extrudate with 35 millimeters KMDL (Krauss-Maffei) forcing machine with 3 inches wide improvement Celuka sheet die and three-roller calendar.Charging is set and is equaled 8.5.

The temperature of screw/barrel #1/ machine barrel #2/ mouth mould is respectively 175 ℃/195 ℃/185 ℃/198 ℃.The air knife of mouthful mould of blowing off in mouth mould exit is used for cooling extruded thing epidermis, keeps expanded thickness to allow extrudate.Top roller on the roller rolling press (chromium) passes through on sheet material top, so that smooth surface.On the chromium roller, do not use blast, to avoid the foam structure of crushing.Cooling extruded thing before extrudate is pulled out by rubber roll.The quality of powder property, forcing machine performance and foaming extrudate and density the results are shown in table 12.

Table 9

Table 10

Table 11

Table 12

Compare with 25 with embodiment 23, after blend was finished, embodiment 24 had the wet branch of minimum residual powder, minimum extrudate density and the minimum residence time of wood powder in blending machine.Embodiment 24 is also shown in the blend loop start and wood powder is added with PVC and whipping agent causes the fluff packing powder density high and leakage current is fast, extrusion pressure is low, output speed is high and extrudate is superior in quality.

Embodiment 25 also shows owing to following reason does not more wish to add wood powder at last at the blend round-robin, and it needs the longest blend time, cause the residual powder of powder wet divide the highest, the powder leakage current is slower, extrusion pressure is higher and foaming extrudate density is higher.Embodiment 26 and 27 shows with the blend order identical with embodiment 24 and adds impact modifier with powder or emulsion form, causes that excellent leakage current, low residual powder wetly divide, good extrusion pressure and extrudate density, good extrudate surface quality and higher output speed.

Embodiment 28

The coextrusion of mixture, dyeing and thermoforming

The composition that is used to prepare the PVC/WF foaming powder blend tread rubber of mixture and PVC plate washer matrix is as shown in table 13.Method according to embodiment 26 prepares the PVC/WF powder blend.With 10 " wide bifid pipe sheet die foams the blend tread rubber with the coextrusion of typical plate washer matrix formulation with PVC/WF.Composite sheet by PVC matrix coextrusion 1.04 mm thick of the PVC/WF tread rubber of 0.30 mm thick and 0.74 mm thick.Coverage on the tread band even surpass this width and quite attractive (like wood appearance).

This composite sheet can be used as the vinyl plate washer goods that have like wood appearance.This mixture can be well with saw or shears cutting.

This mixture also can dye.Cut many samples down from this mixture.Various tinting materials are applied to PVC/WF tread rubber surface, comprise that ((At, the Holy Land adds the inferior state of livre Buddhist nun to Behr NaturalSeal Plus#80 to two kinds of oil base accretion toners; The displacement of reservoir oil penetrates former oil-type Redwood, Hudson, Ohio), the agent of two kinds of oil base intrinsic colors (ZAR#138 and ZAR#116, associating Gilsonite laboratory, Scranton, the Pennsyivania) and polyurethane gle intrinsic color agent (elaboration #MC16) and water base intrinsic color agent (Behr#686).Use tinting material with foam brush, and use dry air.Range estimation shows that all tinting materials can both use well.Water based coloring agent provides the most uniform color, and is absorbed the soonest.Oil base and polyurethane-base tinting material show the specific position migration in mixture, and texture type outward appearance is provided.

Composite sheet also can carry out thermoforming.Composite sheet from 1 millimeter of following several 25 cm x, 20 cm x of extrudate cutting easily is thermoformed into 3 centimetres of dark rectangles with Model Number 300X Formech (KingsPark, New York) vacuum forming machine with it.The deep drawn product that has prepared the excellence of no thinning in the tread rubber or stress defective.The wood composite board of thermoforming can be used for many decorative uses, comprises for example interior finish of automobile of the vehicles.

Table 13: the composition of compound tread rubber and matrix

Embodiment 29

Use cooling fluid to increase the method for foaming extrudate swelling

According to embodiment 24 preparation PVC/WF powder blend.When PVC/WF sheet extrudate leaves mouthful mould surface, cooling fluid is pointed to the top and the bottom of PVC/WF sheet extrudate.With two 15 centimetres of aluminium air knives (Part Number 2006, Exair company, Cincinnati, OH) cooling foaming extrudate.The common pressurized air of 65psi is connected on the valving of stepless controlled chilling air flow rate.Air knife is orientated air is pointed to the direction leave mouthful mould and to carry over the extrudate section.Air knife is placed about 5 centimeters in top and bottom apart from the extrudate surface.

Performance with the prepared foaming extrudate in (cooling fluid is to no cooling fluid) sclerosis extrudate surface is as follows: extrudate thickness (6.22 millimeters to 3.81 millimeters); Sheet material density (0.552 grams per milliliter is to 0.655 grams per milliliter).

In the nib of extrudate with the cooling fluid preparation through cutting and place the thin slightly size between following two the chromium dishes of hydromeehanics pressure (industrial city adds livre Buddhist nun Asia for 100 tons of hydrodynamicpressures of PHI, Pasadena Hydraulics company).The extrudate that in compacting for the first time, adds thermal cutting, and (temperature/pressure/time) cooling under the following conditions in compacting for the second time: 190 ℃/80 tons/30 seconds for the first time, 25 ℃/80 tons/90 seconds for the second time.The extrudate of gained is harder, and has the outward appearance of aesthetic.

Claims (23)

1. extrudable admixture of powder composition, it comprises: (a) at least a ethylene chloride base resin of 30-65 weight %; (b) at least a thermo-stabilizer of 0.25-5 weight %; (c) at least a lubricant of 1.5-5 weight %; (d) at least a polymer processing aid of 3.5-15 weight %; (e) at least a cellulosic materials of 24-65 weight %.

2. according to the composition of claim 1, it further contains at least a whipping agent of 5 weight % at the most.

3. according to the composition of claim 1, it further contains at least a mineral filler of 20 weight % at the most.

4. according to the composition of claim 1, it further contains at least a impact modifier of 15 weight % at the most.

5. according to the composition of claim 1, wherein (a) at least a ethylene chloride base resin is PVC.

6. the composition of claim 1, wherein (d) at least a cellulosic materials is a wood powder.

7. extrudable free flowing powder blend composition, it comprises: (a) at least a polyvinyl chloride resin of 40-55 weight %; (b) at least a thermo-stabilizer of 0.5-1.5 weight %; (c) at least a lubricant of 1.5-3 weight %; (d) at least a polymer processing aid of 5-10 weight %; (e) at least a wood powder of 34-52 weight %; (f) at least a mineral filler of 3-15 weight %; (g) at least a whipping agent of 3 weight % at the most.

8. the composition of claim 7, it further contains at least a impact modifier of 10 weight % at the most.

9. by the extrudate of the preparation of compositions of claim 1 or 7.

10. method for preparing extrudable powder blend, may further comprise the steps: (I) will comprise the mixture blend of following component: (a) at least a ethylene chloride base resin of 30-65 weight %; (b) at least a thermo-stabilizer of 0.25-5 weight %; (c) at least a lubricant of 1.5-5 weight %; (d) at least a polymer processing aid of 3.5-15 weight %; (e) at least a cellulosic materials that contains wet branch of 24-65 weight %.(II) is in (I) blend step more than the elevated temperature to 50 ℃; (III) removes water vapour.

11. according to the method for claim 10, wherein wet minute total amount in the extrudable powder blend in step (III) back is lower than 3 weight %.

12. according to the method for claim 11, wherein before adding (c) at least a lubricant at least a ethylene chloride base of at first blend of the temperature more than 80 ℃ (a) resin and (e) at least a cellulosic materials.

13. a method for preparing extrudable free flowing powder blend may further comprise the steps: (I) will comprise the mixture blend of following component: (a) at least a polyvinyl chloride resin of 40-55 weight %; (b) at least a thermo-stabilizer of 0.5-1.5 weight %; (c) at least a lubricant of 1.5-3 weight %; (d) at least a polymer processing aid of 5-10 weight %; (e) at least a wood powder that contains wet branch of 34-52 weight %; (f) at least a mineral filler of 3-15 weight %; (g) at least a whipping agent of 3 weight % at the most.(II) is in (I) blend step more than the elevated temperature to 80 ℃; (III) removes water vapour, so that the final water capacity in the powder blend is lower than 2.0 weight %.

14. according to the method for claim 13, wherein before adding (c) at least a lubricant, at least a polyvinyl chloride resin of at first blend (a) and (e) at least a wood powder under the temperature more than 80 ℃.

15. according to the method for claim 13, wherein final water capacity is lower than 1 weight %.

16. according to the method for claim 13, wherein this mixture further contains at least a impact modifier of 15 weight % at the most.

17. according to the method for claim 13, the total amount of wherein adding water during adding component (a)-(f) is less than or equal to 25 weight %.

18. according to the method for claim 17, wherein at least a in the component (a) to (f) provides with aqueous-based dispersions.

19. a method for preparing the extrudate that foams may further comprise the steps: the extrudable free flowing powder blend that (I) will contain at least a whipping agent adds in the forcing machine; (II) melted powder blend is to form melt; (III) has the foaming extrudate at least one surface with formation from mouth mould melt extrusion; (IV) is with the surface of cooling fluid sclerosis foaming extrudate, to improve the expansion ratio of foaming extrudate.

20. according to the method for claim 19, wherein cooling fluid is to point to the gas that leaves mouthful mould surface and point to the direction on extrudate surface.

21. mixture, it contains the base layer of extrudable thermoplastic resin, with at least one stratification tread band thereon, one deck tread band contains extrudable free flowing powder blend composition at least, and said composition comprises: at least a polyvinyl chloride resin of 40-55 weight %; 0.5-1.5 at least a thermo-stabilizer of weight %; 1.5-3 at least a lubricant of weight %; At least a polymer processing aid of 5-10 weight %; At least a wood powder of 34-52 weight %; At least a mineral filler of 3-15 weight %; At least a whipping agent of 3 weight % at the most.

22. according to the mixture of claim 21, wherein tread band is through hyperchromatic.

23. according to the mixture of claim 21, wherein this mixture is thermoforming.