Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L33/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
  • C08L33/04—Homopolymers or copolymers of esters
  • C08L33/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, which oxygen atoms are present only as part of the carboxyl radical
  • C08L33/10—Homopolymers or copolymers of methacrylic acid esters
  • C08L33/12—Homopolymers or copolymers of methyl methacrylate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
  • B29C43/003—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
  • B29C45/0001—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
  • B29C48/022—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the choice of material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C49/00—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor
  • B29C49/0005—Blow-moulding, i.e. blowing a preform or parison to a desired shape within a mould; Apparatus therefor characterised by the material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/02—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising combinations of reinforcements, e.g. non-specified reinforcements, fibrous reinforcing inserts and fillers, e.g. particulate fillers, incorporated in matrix material, forming one or more layers and with or without non-reinforced or non-filled layers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F2/00—Processes of polymerisation
  • C08F2/12—Polymerisation in non-solvents
  • C08F2/16—Aqueous medium
  • C08F2/22—Emulsion polymerisation
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/10—Esters
  • C08F220/12—Esters of monohydric alcohols or phenols
  • C08F220/14—Methyl esters, e.g. methyl (meth)acrylate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
  • C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
  • C08F220/10—Esters
  • C08F220/12—Esters of monohydric alcohols or phenols
  • C08F220/16—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms
  • C08F220/18—Esters of monohydric alcohols or phenols of phenols or of alcohols containing two or more carbon atoms with acrylic or methacrylic acids
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
  • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
  • C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
  • C08J9/14—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
  • C08J9/142—Compounds containing oxygen but no halogen atom
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L27/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Compositions of derivatives of such polymers
  • C08L27/02—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L27/12—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Compositions of derivatives of such polymers not modified by chemical after-treatment containing fluorine atoms
  • C08L27/16—Homopolymers or copolymers or vinylidene fluoride
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
  • C08L51/04—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to rubbers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
  • C08L67/04—Polyesters derived from hydroxycarboxylic acids, e.g. lactones
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2033/00—Use of polymers of unsaturated acids or derivatives thereof as moulding material
  • B29K2033/04—Polymers of esters
  • B29K2033/08—Polymers of acrylic acid esters, e.g. PMA, i.e. polymethylacrylate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2201/00—Foams characterised by the foaming process
  • C08J2201/02—Foams characterised by the foaming process characterised by mechanical pre- or post-treatments
  • C08J2201/024—Preparation or use of a blowing agent concentrate, i.e. masterbatch in a foamable composition
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2333/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
  • C08J2333/04—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters
  • C08J2333/06—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters of esters containing only carbon, hydrogen, and oxygen, the oxygen atom being present only as part of the carboxyl radical
  • C08J2333/10—Homopolymers or copolymers of methacrylic acid esters
  • C08J2333/12—Homopolymers or copolymers of methyl methacrylate
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2433/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers
  • C08J2433/04—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters
  • C08J2433/06—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Derivatives of such polymers esters of esters containing only carbon, hydrogen, and oxygen, the oxygen atom being present only as part of the carboxyl radical
  • C08J2433/08—Homopolymers or copolymers of acrylic acid esters
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2207/00—Properties characterising the ingredient of the composition
  • C08L2207/53—Core-shell polymer

Definitions

• the invention relates to an acrylic formulation having a thermoplastic matrix and 1-40 percent by weight of a very high molecular weight acrylic processing aid, with a weight average molecular weight of greater than 5,000,000 Daltons.
• the formulation has a high melt strength, yet is processable under typical melt processing conditions.
• the formulation is useful for forming melt-processed products, including extruded products such as extruded sheet, foamed products, co-extruded profiles, blown films, and other objects typically formed by a heat processing operation.
• the invention is especially useful with an acrylic matrix, such as
• Thermoplastics are highly versatile polymers which are easily melt-processed into many different shapes, such as profiles, sheets, rods; molded and blow molded into films and objects; and extruded or co-extruded over many other thermoplastic substrates.
• Acrylic polymers are a specific class of thermoplastics that are well known for their clarity, surface gloss and weather resistance.
• the melt strength of a thermoplastic polymer formulation is a key factor in the success of many melt-process operations.
• higher melt strength prevents uncontrolled expansion of the foam cells, to provide a small, uniform cell size.
• Higher melt strength also prevents a foam from collapsing prior to cooling, and locks in the foam structure.
• the high melt strength allows the pulling of a hot, extruded solid or foamed material through sizing or calibrating equipment.
• high melt strength provides the polymer melt with integrity, so a continuous material is formed without gaps.
• One way to increase the melt strength of a polymer formulation is to incre; molecular weight of the polymer.
• melt viscosity can quickly increase to the point that the melt is too thick to process in typical melt processing equipment.
• Higher melt strength is also known to result from the presence of the higher degree of long chain branching and network/cross -linked structures that can be found in the very high molecular weight process aids.
• Long chain branching can be introduced in polymers via irradiation or by modification of the polymerization process.
• the invention relates to a high melt strength acrylic formulation comprising: a) an acrylic matrix comprising an acrylic polymer;
• the invention further relates to a high strength acrylic formulation in which the matrix is may optionally be impact-modified.
• the invention further relates to articles that are made from the high impact strength acrylic formulation, and also to melt processes for forming those articles.
• Figure 1 shows the increase of the melt strength of a PMMA matrix formulation having a lower molecular weight process aid (1.5 million g/mol) compared to a PMMA matrix formulation having a very high (10 million g/mol) process aid.
• Figure 2 shows the effect of enhanced melt strength on the strain hardening behavior and transient extensional viscosity increase for a formulation of the invention.
• Figure 3 shows the effects on the shear rates of formulations of the invention.
• the invention relates to an acrylic formulation having a high melt strength, yet where the formulation is processable under typical melt-processing conditions.
• the formulation contains 1-40 weight percent, preferably from 3 to 25 weight percent, and most preferably from 5 to 15 weight percent of a very high molecular weight acrylic polymer process aid, and a matrix acrylic polymer, that is optionally impact modified.
• Copolymer is used to mean a polymer having two or more different monomer units.
• Polymer is used to mean both homopolymer and copolymers. Polymers may be straight chain, branched, star, comb, block, or any other structure. The polymers may be homogeneous, heterogeneous, and may have a gradient distribution of co-monomer units. All references cited are incorporated herein by reference. As used herein, unless otherwise described, mean weight percent. Molecular weight is a weight average molecular weight as measured by GPC. In cases where the polymer contains some cross -linking, and GPC cannot be applied due to an insoluble polymer fraction, soluble fraction / gel fraction or soluble faction molecular weight after extraction from gel is used.
• the acrylic polymer process aids of the invention are very high molecular weight acrylic polymers.
• Other polymers miscible with polymethyl methacrylate may also be used in conjunction with the high molecular weight acrylic polymer, including but not limited to polylactic acid and polyvinylidne fluoride.
• very high molecular weight is meant that the polymers have a weight average molecular weight of greater than 5 million Dalton, preferably greater than 6 million Dalton, and more preferably greater than 8 million Dalton.
• Acrylic polymers having a weight average molecular weight of about 10 million Dalton or greater are also contemplated by the invention.
• the acrylic process aid preferably contains at least 50 weight percent of methyl methacrylate monomer units, and optionally comonomers, up to 50 weight percent.
• the methyl methacrylate monomer units make up from greater than 50 to 100 percent of the monomer mixture, preferably from 70 to 100 weight percent, and more preferably from 80 to 100 weight percent. 0 to less than 50 weight percent of other acrylate and methacrylate monomers or other ethylenically unsaturated monomers, included but not limited to, styrene, alpha methyl styrene, acrylonitrile, and crosslinkers at low levels may also be present in the monomer mixture.
• Suitable acrylate and methacrylate comonomers include, but are not limited to, methyl acrylate, ethyl acrylate and ethyl methacrylate, butyl acrylate and butyl methacrylate, iso-octyl methacrylate and iso-octyl acrylate, lauryl acrylate and lauryl methacrylate, stearyl acrylate and stearyl methacrylate, isobornyl acrylate and isobornyl methacrylate, methoxy ethyl acrylate and methoxy methacrylate, 2-ethoxy ethyl acrylate and 2-ethoxy ethyl methacrylate, and
• dimethylamino ethyl acrylate and dimethylamino ethyl methacrylate monomers can be useful for the monomer mixture.
• acrylic acids such as methacrylic acid and acrylic acid can be useful for the monomer mixture.
• other functionality can be added to the high molecular weight acrylic process aid through functional comonomers, including epoxy (such as glycidyl methacrylate), hydroxyl, and anhydride functional groups.
• Functional monomer i (monomer units having a functional group) can be present at up to 70 weight percent of the acrylic polymer, preferably up to 50 weight percent.
• the acrylic polymer is a copolymer having 70 - 99.5 weight percent and more preferably 80 to 99 percent of methyl methacrylate units and from 0.5 to 30 weight percent of one or more C 1-8 straight or branched alkyl acrylate units.
• the polydispersity index of the high molecular weight acrylic process aid is in the range of 1.5 to 50, preferably from 2 to 40, and most preferably from 3 to 30.
• the high molecular weight acrylic process aid has a Tg of from -60 to 140°C, preferably from 0 to 120°C.
• the acrylic polymer can be an alloy with one or more compatible polymers, including ASA, PVDF and PLA.
• Preferred alloys are PMMA/polyvinylidene fluoride (PVDF) alloys, and PMMA/polylactic acid (PLA) alloys.
• the alloy contains 20 to 99 weight percent, preferably 50 to 95 weight percent, and more preferably 60-90 weight percent of the thermoplastic matrix, and 5 to 40 weight percent, preferably 10 to 30 weight percent of the compatible polymer.
• the high molecular weight acrylic process aid can be formed by any known polymerization process, such as emulsion, suspension, solution and reverse emulsion
• the polymer matrix of the invention is composed of one or more acrylic polymers.
• the acrylic polymer matrix is meant to include polymers, and copolymers having two or more different monomer units that are formed from alkyl methacrylate and alkyl acrylate monomers, and mixtures thereof.
• the alkyl methacrylate monomer is preferably methyl methacrylate, which may make up from greater than 50 to 100 percent of the monomer mixture, preferably from 70 to 100 weight percent, and more preferably from 80 to 100 weight percent. 0 to less than 50 weight percent of other acrylate and methacrylate monomers or other
• ethylenically unsaturated monomers included but not limited to, styrene, alpha methyl styrene, acrylonitrile, and crosslinkers at low levels may also be present in the monomer m
• Suitable acrylate and methacrylate comonomers include, but are not limited to, methyl acrylate, ethyl acrylate and ethyl methacrylate, butyl acrylate and butyl methacrylate, iso-octyl methacrylate and iso-octyl acrylate, lauryl acrylate and lauryl methacrylate, stearyl acrylate and stearyl methacrylate, isobornyl acrylate and isobornyl methacrylate, methoxy ethyl acrylate and methoxy methacrylate, 2-ethoxy ethyl acrylate and 2-ethoxy ethyl methacrylate, and
• polystyrene resin (monomer units having a functional group) can be present at up to 70 weight percent of the acrylic polymer, preferably up to 50 weight percent.
• the acrylic polymer is a copolymer having 70 - 99.5 weight percent and more preferably 80 to 99 percent of methyl methacrylate units and from 0.5 to 30 weight percent of one or more C 1-8 straight or branched alkyl acrylate units.
• the acrylic polymer can be an alloy with one or more compatible polymers, including ASA, PVDF and PLA.
• Preferred alloys are PMMA/polyvinylidene fluoride (PVDF) alloys, and PMMA/polylactic acid (PLA) alloys
• PVDF PMMA/polyvinylidene fluoride
• PLA PMMA/polylactic acid
• the alloy contains 2 to 95 weight percent, preferably 5 to 90 weight percent, and more preferably 20-80 weight percent of the PMMA homopolymer or copolymer, and 5 to 98 weight percent, preferably 10 to 95 weight percent and more preferably 20 to 80 weight percent of the compatible polymer.
• the acrylic polymer matrix may contain additives, including impact modifiers, and other additives typically present in polymer formulations, including but not limited to, stabilizers, plasticizers, fillers, coloring agents, pigments, dyes, antioxidants, antistatic agents, surfactants, toner, refractive index matching additives, matting agents, cross-linked polymer beads, additives with specific light diffraction, light absorbing, or light reflection characteristics, and dispersing aids.
• an additive is provided to help prevent degradation of the composition upon exposure to radiation, such as high levels of UV radiation or gamma radiation.
• Useful radiation stabilizers include, but are not limited to poly(ethylene glycol), poly(propylene glycol), butyl lactate, and carboxylic acids such as lactic acid, oxalic acid, acetic acid, or a thereof.
• a chemical blowing agent such as monosodium citrate may be
• thermoplastic formulation especially in a compounding step below the activation temperature of the blowing agent, or dry blended into the formulation immediately before foam extrusion.
• Useful impact modifiers include block copolymers, graft copolymers, and core/shell impact modifiers that are refractive-index matched to the matrix polymer.
• the impact modifier comprises at least 50 weight percent of acrylic monomer units.
• the impact modifier may be present at a level of from 0 to 80 weight percent, preferably 5 to 45, and more preferably from 10 to 30 weight percent, based on the total layer of matrix polymer and all additives. The level of impact modifier can be adjusted to meet the toughness needs for the end use of the composition.
• Core-shell impact modifiers are multi-stage, sequentially-produced polymer having a core/shell particle structure of at least two layers.
• the core- shell impact modifier has a soft (elastomeric) core, and a hard shell (greater than a Tg of 20°C).
• the core-shell modifier comprises three layers made of a hard core layer, one or more intermediate elastomeric layers, and a hard shell layer.
• the impact modifier is a core- shell structure, in which the shell contains at least 50 weight percent of methyl methacrylate monomer units.
• the core-shell impact modifier has a hard core (with a Tg greater than 30°C, and more preferably greater than 50°C).
• the core-shell impact modifier is made entirely of acrylic monomer units.
• the acrylic matrix polymer, high molecular weight acrylic processing aid, and optional impact modifiers and other additives are blended in the melt.
• Two or more of the components of the thermoplastic formulation may first be dry blended, then melt blended.
• the high molecular weight acrylic polymer, acrylic matrix polymer and optionally impact modifier are melt blended together and formed into pellets. The pellets are then added with other components, such as dyes, fillers, and blowing agents at the melt processer operation.
• heat compounding can be accomplished by typical twin screw extrusion into an acrylic formulation.
• Single screw extruders, and extruders of other designs are also contemplated by the invention
• emulsions of one or more of the process aids, acrv polymer and/or impact modifier can be blended as liquid dispersions, and the blend can be dried, such as by spray drying, coagulation, or freeze drying, to form a powder blend.
• the powder blend can then be further compounded with other components of the acrylic formulation either by dry blending or melt blending. Powder-powder blending is contemplated.
• An intermediate step, in which the spray-dried powder(s) are extrusion melt compounded into pellets for further melt compounding is also contemplated.
• Typical melt processing operations in which the high melt strength acrylic formulation of the invention, having a manageable melt viscosity may be useful include, but are not limited to, extrusion, co-extrusion, injection molding, compression molding, film extrusion, and blow molding operations.
• the very high molecular weight, very high polydispersity formulation of the invention undergoes significant shear thinning, so its effect on high shear viscosity will be minimal.
• Process aids of the invention having higher levels of long chain branching can more effectively increase the melt strength.
• the acrylic formulations of the invention are useful in melt-processing applications that can benefit from a high melt strength with little increase in melt viscosity. These include, but are not limited to foams, profile coextrusion, thermoforming, and melt blown films.
• foams profile coextrusion, thermoforming, and melt blown films.
• melt blown films melt blown films.
• a high melt strength formulation provides several advantages in a foaming operation.
• the high melt strength provides control over the expansion of the individual cells, allowing for a more uniform cell size, and smaller cell size. Die swell of the foam is also better controlled.
• the high melt strength also helps to prevent the collapse of the cells, once formed. Further, the extruded foam can be more easily sized and/or calendared without deforming the foamed article, due to the higher melt strength of the polymer
• the higher melt strength acrylic process aid provide continuity to the thermoplastic formulation, leading to little or no gaps or pit marks in the acrylic layer, and further there is an increase in die swell to better match the coextruded substrate.
• PD-1136 5 to 10 weight percent is melt compounded in a twin screw extruder into SOLARKOTE H300-103 (Arkema Inc.), which is an impact modified acrylic polymer, and extruded over a thermoplastic olefin substrate as a capstock profile extrusion.
• strain hardening helps with stabilization of the cellular structure during foam process which is attributed to the presence of entanglements; consequently macromolecules lose the ability to disentangle quickly enough to follow exponential deformation.
• the molecular weight of the acrylic processing aid described in this example will be about 6 million g/mol., measured as the mass average molecular weight (Mw) of the polymers by size exclusion chromatography (SEC).
• Another processing aid with specific anti-sticking composition such, as the one described in the patent EP 0367 198 B l could also be used in the process.
• the two processing aids would be co-spray dried using 10 wt. % of the anti-sticking processing aid and 90 wt. % of the processing aid described by the preparation earlier in this example.
• Co-spray drying as used in this example consists of blending the two acrylic processing aid latexes and then isolating the blend by spray drying. This results in a final powder particle or grain comprised of both processing aids.
• acrylic resin Plexiglas® VS lOO, Arkema Inc., King of Prussia, PA
• 105 grams 5 wt. % of the processing aid combination described above with 90 wt. % of the high molecular weight component and 10 wt. % of the anti-sticking processing aid.
• the acrylic formulation would be melt compounded in a twin screw extruder in order to homogenize the thermoplastic matrix and processing aids.
• the acrylic formulation would have both high melt strength and improved anti-sticking (better metal release). Aspects of the invention include:
• a high melt strength thermoplastic formulation comprising: a) an acrylic matrix comprising at least one acrylic polymer; b) 1 to 40 weight percent of a very high molecular weight acrylic process aid, wherein said very high molecular weight acrylic process aid has a molecular weight or greater than 5 million Daltons.
• said acrylic process aid comprises 50 to 100 weight percent of methyl methacrylate monomer units, and from 0 to 50 weight percent of one or more monomer units selected from the group consisting of (meth)acrylates, styrene, alpha methyl styrene, acrylonitrile, glycidyl methacrylate, and
• (meth) acrylic acid 4.
• acrylic polymer matrix further comprises at least one additive selected from the group consisting of stabilizers, plasticizers, fillers, coloring agents, pigments, dyes, antioxidants, antistatic agents, surfactants, toner, refractive index matching additives, matting agents, cross-linked polymer beads, additives with specific light diffraction, light absorbing, or light reflection characteristics, and dispersing aids.
• additives selected from the group consisting of stabilizers, plasticizers, fillers, coloring agents, pigments, dyes, antioxidants, antistatic agents, surfactants, toner, refractive index matching additives, matting agents, cross-linked polymer beads, additives with specific light diffraction, light absorbing, or light reflection characteristics, and dispersing aids.
• said article is a sheet, film, rod, profile, or co-extruded sheet, film, profile, or co-extruded capstock over a substrate, and may be solid or a foam.

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• 2017
  • 2017-03-24 KR KR1020187031005A patent/KR20180128033A/ko not_active Ceased
  • 2017-03-24 EP EP17771220.5A patent/EP3432893B1/en active Active
  • 2017-03-24 WO PCT/US2017/023982 patent/WO2017165743A1/en not_active Ceased
  • 2017-03-24 MX MX2018011567A patent/MX2018011567A/es unknown
  • 2017-03-24 JP JP2018550355A patent/JP2019509389A/ja active Pending
  • 2017-03-24 US US16/086,020 patent/US20200291154A1/en active Pending

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