Reduction of tack in laser-cut, impact-modified acrylic resin

Abstract

An acrylic resin composition is provided. The acrylic resin includes 32.5 to 94.95 weight percent of at least one acrylic polymer resin; 5 to 65 weight percent of one or more impact modifiers; and 0.05 to 5.0 weight percent of at least one tack-reducing material. The acrylic resin composition, when laser cut to produce a laser-cut surface, has a tack on the laser-cut surface, as measured by a 5N force meter, of less than 0.1N.

Description

[0001] REDUCTION OF TACK IN LASER-CUT, IMPACT-MODIFIED ACRYLIC RESIN

[0002] CROSS-REFERENCE TO RELATED APPLICATION

[0003] This application claims priority to United States Provisional Application No. 63 / 570,306, filed March 27, 2024, and the contents of which are incorporated herein by reference in their entireties for all purposes.

[0004] FIELD OF THE INVENTION

[0005] The invention relates to an impact-modified acrylic resin composition having a reduced tack on surfaces that have been cut using very high heat, such as with a CO2 laser.

[0006] BACKGROUND OF THE INVENTION

[0007] Lasers, especially CO2 lasers, are useful in cutting certain polymeric substances, and articles made of the same. The high point-heat of these lasers, in the range of 5000 to 6000°C, can decompose and / or volatilize the polymer. For example, laser cutting with a CO2 laser is effective on articles comprised of polyolefins, as described in US 2016 / 0185087A1.

[0008] It is also known that acrylic resins, such as polymethyl methacrylate (pMMA) resin may be laser cut and engraved by CO2 lasers. The depolymerization of acrylic resins is very efficient.

[0009] Unmodified pMMA polymers are known to be brittle. To reduce the brittleness, impact modifiers may be added to the composition, generally at levels of 5 to 70 weight percent, based on the polymer composition. Such impact modifiers may include linear block copolymers containing a rubber block, and core-shell graft copolymers having a rubber core and a hard shell.

[0010] When laser cutting an impact-modified acrylic resin, the rubber in the impact modifier generally does not degrade completely. This incomplete degradation leaves an undesirable accumulation of tacky residue on the laser treated surfaces. The resulting tacky residue buildup must then be cleaned from each cut surface. By "tack" and "tacky", as used herein is meant a slightly sticky feeling.

[0011] SUMMARY OF THE INVENTION

[0012] In one embodiment, an acrylic resin composition is provided. The acrylic composition includes: 32.5 to 94.95 weight percent of at least one acrylic polymer resin; 5 to 65 weight percent of one or more impact modifiers; 0.05 to 5.0 weight percent of at least one tack-reducing material, having a weight average particle size range of from 0.01 micrometers to 10 micrometers. The acrylic resin composition of the invention, when laser cut, has a tack on the laser-cut surface, as measured by a 5N force meter from Torbal, of less than 0.1N. In another embodiment, a method for laser cutting an acrylic film, sheet or profile using a CO2 laser includes the steps of providing an acrylic polymer; incorporating 5 to 65 weight percent of one or more impact modifiers into the acrylic polymer to form a modified acrylic polymer composition; incorporating 0.05 to 5.0 weight percent of at least one tack-reducing material, having a weight average particle size range of from 0.01 micrometers to 10 micrometers into said modified acrylic polymer composition; forming a film, sheet or profile of said modified acrylic polymer composition; and using a laser to cut or engrave said modified acrylic film, sheet or profile. The cut edge of the modified acrylic film, sheet or profile has a tack of less than 0.1N as measured by a 5N force meter from TorbaL

[0013] DETAILED DESCRIPTION OF THE INVENTION

[0014] Surprisingly it was found that fumed silica at a loading of only 0.5 to 2%, reduced the surface tack to near zero, with no noticeable reduction in impact properties of an impact-modified acrylic resin when laser cut. Other tack-reducing additives were found to produce a similar effect.

[0015] While not being bound to any particular theory, it is believed that local heating of the tack-reducing materials may cause better volatilization of the tacky residues, or may increase the modulus at the cut to hide tack. The high surface area of the tackreducing materials may also reduce the flow of the impact modifier residue, thus avoiding a tacky condition.

[0016] It was unexpected that the addition of such low levels of inorganic or organic materials would result in such a large reduction in tack on a laser-cut surface. In some embodiments, the resulting tack was near zero. The tack-reducing materials of the invention are generally avoided in impact-modified acrylic polymer compositions, as they tend to make an acrylic material more brittle - the opposite of the desired effect of impact-modification. The melt flow rate also tends to decrease with the addition of additives, such as the tack-reducing materials of the invention. It is an important parameter of the invention to retain the impact resistance of the impact-modified acrylic resin, along with retention of other properties, such as melt-flow rate, tensile strength, etc. The final product may be opaque or translucent or opaque, depending on the tack-reducing material used.

[0017] "Copolymer" as used herein means a polymer having two or more different monomer units, including copolymers, and polymers with three or more different monomers, such as terpolymers and tetrapolymers. Accordingly, the terms "co-, ter- and tetra-polymer" encompass any polymer having more than one type of comonomer. "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, percent shall mean weight percent. Molecular weight is a weight average molecular weight as measured by gel permeation chromatography (GPC) using polymethylmethacrylate standards. In cases where the polymer contains some crosslinking, 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 to determine weight average molecular weight. "(Meth)acrylic" or "(meth)acrylate" as used herein denotes both the acrylate and the methacrylate.

[0018] (Meth)acrylic polymer

[0019] (Meth)acrylic polymers, as used herein, include, but are not limited to, homopolymers, copolymers and terpolymers (meaning more than two different monomer units) comprising alkyl (meth)acrylates. Blends of two or more different (meth)acrylic polymers are also contemplated.

[0020] The alkyl methacrylate monomer is preferably methyl methacrylate, which makes up from 60 to 100 of the monomer mixture. 0 to 40 percent of other acrylate, methacrylate, and / or other vinyl monomers may also be present in the monomer mixture. The comonomers generally make up from 0.5 to 40 weight percent, preferably from 0.5 to 30 weight percent, and preferably from 2 to 20 weight percent of the (meth)acrylate copolymer. Other methacrylate, acrylate, and other vinyl monomers useful in the monomer mixture include, but are not limited to, methyl acrylate, ethyl acrylate and ethyl methacrylate, butyl acrylate and butyl methacrylate, iso-octyl methacrylate and acrylate, ethyl hexyl acrylate and methacrylate, lauryl acrylate and lauryl methacrylate, stearyl acrylate and stearyl methacrylate, isobornyl acrylate and methacrylate, methoxy ethyl acrylate and methacrylate, 2-ethoxy ethyl acrylate and methacrylate, dimethylamino ethyl acrylate and methacrylate monomers, styrene and its derivatives. Alkyl (meth) acrylic acids such as (meth)acrylic acid and acrylic acid can be useful for the monomer mixture. Small levels of multifunctional monomers as crosslinking agents may also be used. A preferred acrylic polymer is a copolymer of methyl methacrylate and 2-16 percent of one or more Cl-4 acrylates.

[0021] The Tg of the (meth)acrylic polymer of the invention is preferably greater than 90°C, preferably greater than 95°C, and more preferably greater than 102°C. Impact modifiers

[0022] The impact resistance of acrylic resins can be improved by the incorporation of high levels of impact modifiers. For many applications, a non-impact (meth)acrylic polymer could be too brittle for use, and an impact modified (meth)acrylic would be preferred. The composition of the invention contains from 5 to 70, preferably 10 to 60, preferably 20 to 50, more preferably 25 to 50 weight percent, of one or more impact modifiers, based on total weight of the composition.

[0023] Impact modifiers useful in the invention include, but are not limited to, block copolymers, and core-shell impact modifiers. The core-shell impact modifier may have a soft-hard morphology, a hard core-soft (elastomeric) layer-hard shell morphology, or similar other morphologies. Multiple shell layers are also contemplated. The elastomeric layer has a Tg of less than 10°C, preferably less than 0°C.

[0024] Preferred core-shell impact modifiers have a hard core with a Tg greater than 30°C and more preferably greater than 50°C. The core-shell impact modifiers have a volume average particle size of from 70 to 350 nm, preferably 100 to 350 nm, preferably 150-300, more preferably from 200-250 nm. Bimodal distribution, or other particle size distribution of the impact modifies is also contemplated.

[0025] In one preferred embodiment, the core-shell impact modifier has an acrylic shell.

[0026] The hard core layer can be chosen from any monomer combination meeting the Tgrequirements. Preferably, the hard core layer is composed primarily of methacrylate ester units, acrylate ester units, styrenic units, or a mixture thereof. Methacrylate esters units include, but are not limited to, methyl methacrylate, ethyl methacrylate, n- propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, pentadecyl methacrylate, dodecyl methacrylate, isobomyl methacrylate, phenyl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, 2-hydroxyethyl methacrylate and 2- methoxyethyl methacrylate. Acrylate ester units include, but are not limited to, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n- butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, cycloheyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, dodecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, phenoxyethyl acrylate, 2-hydroxyethyl acrylate and 2-methoxyethyl acrylate. Preferably the acrylate ester units are chosen from methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate and octyl acrylate. Styrenics units include styrene, and derivatives thereof such as, but not limited to, alpha-methyl styrene, and para methyl styrene. In one embodiment the hard core layer is all-acrylic. In another embodiment the hard core layer is acrylic with <30% styrenic monomer units.

[0027] At least one intermediate rubber layer or layers are elastomeric, having a Tg of less than 0 °C, and preferably less than -20 °C. Preferred elastomers include polymers and copolymers of alkyl acrylates, dienes, styrenics, and mixtures thereof. Preferably the soft intermediate layer is composed mainly of acrylate ester units. Acrylate ester units useful in forming the soft block include, but are not limited to, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, cycloheyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, dodecyl acrylate, isobornyl acrylate, phenyl acrylate, benzyl acrylate, phenoxyethyl acrylate, 2- hydroxyethyl acrylate and 2-methoxyethyl acrylate. Preferably the acrylate ester units are chosen from methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate and octyl acrylate. Useful dienes include, but are not limited to, isoprene and butadiene. Useful styrenics include, but are not limited to alpha-methyl styrene, and para-methyl styrene. In a preferred embodiment, acrylate ester units comprise >45 wt %, and even >75% of the elastomeric inner layer or layers. Preferably the total amount of elastomeric layer(s) in the impact modifier is from 30-90 weight percent, more preferably from 40-85 weight percent, and most preferably from 55-80 weight percent, based on the total weight of the impact modifier particle.

[0028] The outer hard shell layer can be made of one or more shell layers, having a Tg > 0 °C, more preferably Tg > 20 °C, preferably selected from the list above for the hard core. The outer shell layer may be the same or different composition from the hard-core layer. A level of functionalization may be included in the shell, to aid in compatibility with the polymer matrix. Hydrophilic monomers may also be included in the shell to improve shell coverage or improve anti-blocking properties. Example of useful hydrophilic monomers include but not limited to hydroxy alkyl (meth)acrylates, (meth)acrylic acid, (meth)acrylic amides, (meth)acrylic amines, polymerizable surfactants and macromonomers containing hydrophilic moieties.

[0029] In a preferred embodiment the core-shell impact modifiers of the invention are comprised of greater than 45 weight percent, preferably greater than 50 weight percent, of a rubber, having a Tg of less than 0°C, preferably less than -10°C, more preferably less than -20°C.

[0030] It was found that silicone-based impact modifiers may catch fire at significant loading when used in a laser-cutting process. Tack-reducinq materials

[0031] Low levels of tack-reducing materials are added to the impact-modified acrylic polymer composition at levels of from 0.05 to less than 5 weight percent, preferably from 0.1 to 4 weight percent, more preferably 0.5 to 2 weight percent, based on the weight of the impact-modified acrylic polymer composition. Higher levels of tackreducing materials tend to reduce the melt flow rate of the polymer composition, and also have a negative effect on the impact resistance. Lower levels of tack-reducing agents may result in a small amount of tack on laser-cut surfaces. Higher levels of tack-reducing materials may be desired for impact-modified acrylic polymer compositions having a high level of rubber.

[0032] The tack-reducing materials include both inorganic and organic materials, as well as mixtures of tack-reducing materials. The tack-reducing materials have a weight average particle size range of from 1 nm to 10 micrometers, preferably from 10 nm to 5 micrometers, more preferably from 30 nanometers to 1 micrometer.

[0033] Useful inorganic materials include, but are not limited to silicon dioxide, fumed silica, precipitated silica, aluminum oxide, calcium carbonate, nanodiamond, graphene, transition metal oxides, tin oxide, indium oxide, barium oxide, molybdenum disulfide, boron nitride, tungsten disulfide, nano clays, nano-graphite, and mixtures of two or more of these.

[0034] Preferred inorganic tack-reducing agents include aluminum oxide at 0.5 and 2 wt%, calcium carbonate at 0.5 and 2wt%; nanodiamond at 0.5%, graphene at 0.5% and tin oxide at 0.5% or less. A most preferred tack-reducing material is fumed silica where the primary particles are less than 1 micrometer in diameter.

[0035] Organic tack-reducing materials include, but are not limited to cross-linked acrylic beads, alkaline- earth stearates, zinc stearate, stearyl alcohol, stearic acid, stearamide and mixtures thereof, or mixtures with one or more inorganic tack-reducing materials.

[0036] Other Additives

[0037] The acrylic polymer composition of the present invention may optionally contain, one or more typical additives for polymer compositions used in usual effective amounts, including but not limited to processing aids, stabilizers, plasticizers, fillers, coloring agents, pigments, antioxidants, antistatic agents, surfactants, toner, refractive index matching additives, additives with specific light diffraction, light absorbing, or light reflection characteristics, dispersing aids, radiation stabilizers, carboxylic acids such as lactic acid, oxalic acid, and acetic acid, and light modification additives.

[0038] Process for formina the modified acrylic polymer composition.

[0039] The acrylic resin, impact modifier and tack-reducing material may be combined to form a modified acrylic polymer composition, by any means known and used in the art.

[0040] Some useful examples for incorporation of the tack-reducing material and impact modifier, and optional other additives include the following, which and may be used -1- individually for each added material, or two or more materials may be added to the acrylic polymer in the same step: incorporation of the tack-reducing material by blending a powder of the tackreducing material and impact modifiers with acrylic resin pellets; direct incorporation into a twin-screw extruder melt-stream; blending with another additive powder; incorporation into an additive latex in its colloidal form before spray drying; forming a masterbatch concentrate of one or more of the materials, and diluting into a molten polymer stream, as in a twin-screw extruder. In one embodiment a pre-dispersed silica is compounded into an impact modified acrylic resin stream; isolation of an impact modified powder with colloidal silica prior to compounding; and direct extrusion of a silica loaded impact modifier. This enables easy flow of the powder and easy incorporation of silica.

[0041] The tack-reducing, impact-modified acrylic composition of the invention also applies to acrylic sheet made by a cell-cast process, in which impact modifier and tack-reducing materials are added into the monomer / oligomer used to fill the cells.

[0042] Blending may occur, for example, in a Heschel-type mixer, linear mixer, masterbatching in continuous mixer, etc.

[0043] Once the impact-modified, reduced-tack acrylic composition is formed, it can be formed into a film, sheet, or profile by means typically used in the art, including (co)extrusion, lamination, injection molding, blow molding, calendaring, thermoforming, and other methods known in the art.

[0044] The film, sheet, or profile may be transparent or opaque.

[0045] Laser cuttinq process

[0046] Impact-modified pMMA may be cut and engraved by different methods as known in the art.

[0047] In one embodiment, a CO2 laser is used, having a wavelength of about 11 micrometers. In a laser cutting or engraving process, an impact-modified sheet, film, or profile is generally positioned under the laser. The sample may be single or multilayered. The depth and speed of cutting may be controlled by a computer, for precision cutting, as known in the art.

[0048] The composition of the invention may also provide reduced tack on cut surfaces from other high-temperature operations, such as electric arc welding. In one embodiment, laser-cutting is used to engrave patterns into one or more a multi-layer opaque acrylic composite, in which different layers may have different colors and / or textures. Nameplates, and other engraved films and sheets are possible. Computer-controlled lasers are capable of producing very intricate patterns on surface layer(s) of a multi-layer composite.

[0049] EXAMPLES

[0050] Melt flow rate measurement Instron Ceast MF30 equipment was used for polymers in melt flow rate measurements. The die temperature was controlled at

[0051] 230°C while the loading cell weight was at 3.8kg. The dried pellets were annealed at ~20°C below the Tgover 8 hours.

[0052] Notched Izod i : Notched Izod impact strength or resistance was measured using

[0053] ASTM D256 method with a 1.0J impact hammer at 23°C / 50% relative humidity. The notched Izod bars were injection-molded at the size of 10.2mm (width) x 100mm (long) x3.2mm (thick).

[0054] Tack Measurement The sample was injection molded on a 110 Ton Krauss-Maffei injection molding machine into 4-inch x 6-inch x 0.125-inch clear plastic plates. The plates were then laid on the bed of a 40W CO2 laser engraver / cutter from Monport

[0055] (model 3020) and cut at a speed of 200 mm / min at 20% laser power using Lightburn Software to program a straight line cut for testing.

[0056] The cut edge was tested for tackiness using the following method : A 2-inch cut edge is pressed into a strip of aluminum foil (0.75-inch by 2.25-inch) by applying moderate pressure 5 times before attaching to a micro-force meter from Torbal

[0057] (maximum force measurement of 5N, measured in 0.001N increments). The foil is then peeled from the cut pMMA edge, and the maximum force is recorded. The test is repeated three times to obtain an average maximum peel force.

[0058] Tensile ion The tensile strength, modulus and elongation of the tensile bars was evaluated using Instron Model 4202 at the crosshead speed of 5mm / minute using ASTM D638 method after being preconditioned at 23°C / 48 hours.

[0059] The tensile bar was at 152.4mm in length while the width was at 12.7mm. The sample thickness was at 3.175mm. Strain rate of 1 mm / min until reaches 0.5% strain then 50 mm / min speed.

[0060] Differential scanninq ca The glass transition temperatures (Tg) of acrylic polymers were measured at a heating rate of 10°C / minutes in N2 using TA instruments Q2000 DSC, during the second heating. The first heating was used to heat the sample to 170°C at a heating rate of 10°C / minute, then, the sample was cooled down to 0°C at a cooling rate of 10°C / minute. The sample weight was controlled at 5-

[0061] 10 mg. Haze: Optica haze and light transmission of clear film and / or plaque samples was measured using BYK HazeGard Plus under ASTM method D1003.

[0062] Materials:

[0063] Aerosil® 972 Fumed silica Aerosil® R202 A fumed silica after-treated with polydimethylsiloxane Aerosil® R805 A fumed silica after-treated with organosilane Aerosil® 300 A hydrophilic fumed silica with a high specific area of 300 m2 / g Acrylic Control 1 High impact-PMMA grade

[0064] Acrylic control 2 Mid impact-PMMA grade TS-9660 Fumed silica with hydrophobic surface treatment

[0065] Zinc Oxide np 20 nm Zinc Oxide

[0066] (zano20)

[0067] TiO2 400 nm titanium dioxide (R905)

[0068] Carbon Black 18 - 20 nm carbon black

[0069] Impact Modifier 300 nm diameter impact modifier (hard core / rubber / hard shell morphology)

[0070] Example 1 :

[0071] A concentrate of 5 parts Aerosil® 972 fumed silica in 95 parts impact modified acrylic resin. Acrylic Control 1 (with about 40 wt% impact modifier) manufactured by Trinseo was prepared in a 27 mm co-rotating twin screw extruder from Leistritz. 15 parts of this concentrate was blended with 85 parts of additional Acrylic Control 1 and melt-compounded together in the same extruder to yield pellets containing 0.75% of fumed silica.

[0072] A sample containing 0.75% fumed silica exhibited a tack level of 0.0N of maximum peel force, while the reference sample (Acrylic Control 1 without fumed silica) exhibits over 0.4N of maximum force.

[0073] A standard pMMA resin containing no impact modifier was also cut and tested and found to have 0.00N of peel force. In a pMMA sample having 25 wt% impact modifier and no tack-reducing material, the tack level was about 0.1N of peel force.

[0074] The invention includes impact-modified, tack-reducing acrylic polymer compositions having a maximum peel force tack of less than 0.1N, preferably less than 0.01N, and most preferably less than 0.001N.

[0075] Examples 2-11

[0076] The same procedure as in Example 1 was used, with the material listed in the chart below instead of Aerosil® 972. Compared to the control Acrylic Control 1 with high impact results and tensile strength, the inventive samples have similar impact resistance and tensile strength without the tack issue. Depending on the application, different additive could be selected for optically clear or opaque material.

[0077] TABLE 1A TABLE IB

[0078] TABLE 2A

[0079]

[0080] TABLE 2B

Claims

What is claimed is:

1. An acrylic resin composition comprising : a) 32.5 to 94.95 weight percent of at least one acrylic polymer resin; b) 5 to 70 weight percent of one or more impact modifiers; c) 0.05 to 5.0 weight percent of at least one tack-reducing material; wherein said acrylic resin composition, when laser cut to produce a laser-cut surface, has a tack on the laser-cut surface, as measured by a 5N micro-force meter from Torbal, of less than 0.1N.

2. The acrylic composition of claim 1, wherein said tack-reducing material is present at from 0.1 to 2 weight percent, based on the total composition.

3. The acrylic composition of claim 1, wherein said impact modifier is selected from the group consisting of core / shell impact modifiers, linear block copolymers, and mixtures thereof.

4. The acrylic composition of claim 1, wherein said tack-reducing material is an inorganic material selected from the group consisting of silicon dioxide, fumed silica, precipitated silica, aluminum oxide, calcium carbonate, nanodiamond, graphene, transition metal oxides, tin oxide, indium oxide, barium oxide, molybdenum disulfide, boron nitride, tungsten disulfide, nano clays , nano-graphite, and mixtures of two or more of these.

5. The acrylic composition of claim 1, wherein said tack-reducing material is an organic material, selected from the group consisting of cross-linked acrylic beads, alkaline- earth stearates, zinc stearate, stearyl alcohol, stearic acid, stearamide and mixtures thereof.

6. The acrylic composition of claim 1, wherein said tack-reducing material is a mixture of one or more inorganic tack-reducing materials, and one or more organic tackreducing materials.

7. The acrylic composition of claim 1, wherein said tack-reducing material(s) have a weight average particle size range of from 1 nm to 10 micrometers.

8. The acrylic composition of claim 1, wherein the composition exists in the form of a film, sheet, or profile.

9. The acrylic composition of claim 1, wherein said composition further comprises an effective amount of one or more additives selected from the group consisting of plasticizers, coloring agents, pigments, antioxidants, antistatic agents, surfactants, UV light absorbers, and dispersing aids.

10. The acrylic composition of claim 1, wherein said tack-reducing material has a particle size range of from 30 nanometers to 1 micrometer.

11. A method for laser cutting an acrylic film, sheet or profile using a CO2 laser, said method comprising the steps of: a) providing an acrylic polymer; b) incorporating 5 to 70 weight percent of one or more impact modifiers into said acrylic polymer to form an impact-modified acrylic polymer composition; c) incorporating 0.05 to 5.0 weight percent of at least one tack-reducing material, having a weight average particle size range of from 1 nm to 10 micrometers into said impact-modified acrylic polymer composition; d) forming a film, sheet, or profile of said impact-modified acrylic polymer composition with a tack-reducing material; and e) using a laser to cut or engrave said impact-modified, reduced-tack acrylic film, sheet, or profile, wherein the cut edge of said modified acrylic film, sheet, or profile, has a tack of less than 0.1N as measured by a 5N micro-force meter from Torbal.

12. The method of claim 11, wherein said laser is a CO2 laser.

13. The method of claim 11, wherein said laser provides a wavelength of about 11 microns.

14. The method of claim 11, wherein said tack-reducing material is combined with the impact modified-acrylic polymer in the molten state in a twin-screw extruder.

15. The method of claim 11, wherein said tack-reducing material is added as a powder to impact-modified acrylic resin pellets.

16. The method of claim 15, wherein said addition of tack-reducing material powder to acrylic resin pellets occurs in a Heschel-type mixer or a line mixer.

17. The method of claim 11, wherein said tack-reducing material is added into an additive latex prior to spray drying, followed by adding said spray-dried conglomerate to the molten acrylic resin.

18. The method of claim 11, wherein said tack-reducing material is added by direct extrusion of a silica loaded impact modifier.

19. The method of claim 11, wherein said engraving involves using the laser to remove one layer of a multi-layer modified acrylic film, sheet, or profile.

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