Encapsulated flame retardant compositions, methods of making encapsulated flame retardant compositions, and articles comprising same

Abstract

In one aspect, the present disclosure relates to a flame retardant plastic composition comprising a polymer component and a brominated flame retardant (BrFR), where the BrFR comprises one or more particles at least partially encapsulated by a thermoplastic toughening agent. In some aspects, the encapsulation can take the form of a core-shell structure wherein the shell has an average thickness of about 5 nm to 10 [mu] m. The thermoplastic toughening agent can be selected from the group consisting of styrenic block copolymers, thermoplastic polyurethanes, nitrile rubbers, acrylic elastomers, copolyester elastomers, thermoplastic polyether ester elastomers, thermoplastic amide ether elastomers, chlorinated rubbers, ionomers, thermoplastic vulcanizates, and combinations thereof. The flame-retardant plastic composition additionally comprises a filler and / or a compatibilizer. A method for preparing the flame retardant plastic composition and articles made from the composition are also disclosed.

Description

Background Art

[0001] Various commercial polymers (such as polyolefins, polystyrenes, polyesters and polyamides) from commodity plastics to engineering plastics are widely used in many engineering applications due to their multifunctional properties. However, poor flame retardancy may hinder their use in some applications. This is because most polymers have a relatively low limiting oxygen index (LOI). When the polymer is exposed to fire, the covalently bonded main chain decomposes and burns. There are various types of flame retardant materials that can impart fire resistance to polymers. Among many types of flame retardants, halogen compounds are widely used in polyolefins due to their advantages such as cost-effectiveness, good processability and high flame retardancy. The reason why brominated flame retardants (BrFRs) are effective is mainly due to the acceptable range of bond energy between aliphatic (or aromatic) carbon and bromine. The bond energy is neither too high nor too low, so they are decomposed and neutralize the hydrogen or hydroxyl radicals generated by the fire.

[0002] A common BrFR, brominated polystyrene (BPS), causes a decrease in the mechanical properties of the polyolefins into which it is incorporated, such as tensile strength, flexural strength, and impact strength. Under impact conditions, the fracture toughness value (critical energy release rate, G Ic ) shows a substantial reduction of up to 50% compared to neat PP. In general, the degradation of mechanical properties is due to weak interfacial strength between the two different polymers in the blend. Wei et al. reported the use of styrenic block copolymers to improve the adhesion between PP and polyphenylene ether (Noryl), resulting in improved fracture toughness. Several simulation studies have shown that when rigid spherical particles have a rubber coating above a certain thickness level, the rubber-coated particles can improve the fracture toughness of three-phase polymer composites. However, these modeling studies have limitations, including the assumption that each interface has a perfect boundary. In the case of hard polymer particles, the particle size varies quite significantly depending on the processing conditions. In addition, the adhesion of the interface also depends on the processing conditions, so the overall morphology also varies in a way that cannot be explained by standard models.

[0003] Despite advances in flame retardant polymer research, there remains a lack of compositions that can achieve good flame retardant properties while maintaining high processability using existing equipment and producing articles with excellent mechanical properties. The present disclosure satisfies these needs and others. Summary of the Invention

[0004] According to the purpose of the present disclosure as embodied and widely described herein, the present disclosure relates in one aspect to a flame retardant plastic composition comprising a polymer component and a brominated flame retardant, wherein the brominated flame retardant is composed of one or more particles at least partially encapsulated by a thermoplastic toughening agent. In some respects, the encapsulation can take the form of a core-shell structure, wherein the shell has an average thickness of about 5nm to about 10μm. The thermoplastic toughening agent can be a thermoplastic elastomer, such as, for example, a styrenic block copolymer (with or without maleic anhydride grafting), a thermoplastic polyurethane, acrylonitrile-butadiene rubber, an acrylic elastomer, a copolyester elastomer, a thermoplastic polyetherester elastomer (TPEE), a thermoplastic amide ether elastomer (TAEE), a chlorinated rubber, an ionomer, a thermoplastic vulcanizate, a polyolefin elastomer or any combination thereof. In some respects, the flame retardant plastic composition additionally comprises a filler and / or a compatibilizer, such as, for example, maleic anhydride grafted PP. In addition, a method for preparing a flame retardant plastic composition and an article made from the composition are disclosed.

[0005] Other systems, methods, features, and advantages of the present disclosure will be or will become apparent to those skilled in the art upon review of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this specification, be within the scope of the present disclosure, and be protected by the appended claims. Furthermore, all optional and preferred features and modifications of the described embodiments may be applied to all aspects of the disclosure taught herein. Furthermore, the individual features of the appended claims and all optional and preferred features and modifications of the described embodiments are combinable and interchangeable with each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Many aspects of the present disclosure may be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, but emphasis is placed on clearly illustrating the principles of the present disclosure. Additionally, in the drawings, like reference numerals indicate corresponding parts throughout the several views.

[0007] Figure 1A Schematic diagrams depicting the single notched three-point bend (SN3PB) test geometry are shown. FIG1B shows a top view and front view of the SN3PB. FIG1C shows an optical microscopy (OM) image of a sharp crack. FIG1D shows a top view and front view of the SN3PB test to obtain the U0 term. FIG1E shows an OM image of a cracked specimen.

[0008] Figure 2A Side views showing the initiation of sharp cracks in SN3PB and double-notched four-point bend (DN4PB) specimens below the machined groove. Figure 2B A cross-sectional view showing the fracture surface in the SN3PB specimen after impact fracture.

[0009] Figure 3A shows a schematic diagram depicting the DN4PB test geometry. Figure 3B shows a top view of the DN4PB, and Figure 3C shows a front view of the DN4PB. Figure 3D shows a petrographic thin section on a glass slide and a transmitted light optical microscopy (TOM) image of polypropylene (PP) in the mid-plane (plane strain region) of the specimen from an arrested crack.

[0010] Figures 4A-4D TEM images of four systems are shown: PP / BPS[L]( Figure 4A )、PP / BPS / SEBS[SD]( Figure 4B )、PP / BPS[S]( Figure 4C ) and PP / BPS / SEBS[CS]( Figure 4D The number in the upper left corner of each image represents the average particle size of the BPS in that image. Abbreviations: PP = polypropylene; BPS = brominated polystyrene; SEBS = styrene-ethylene-butylene-styrene; L = large particles and S = small particles (for size information, see Examples); SD = separately dispersed particles; CS = core-shell particles.

[0011] Figure 5A Surface energy versus surface coverage is shown. Figure 5B Interfacial energy versus temperature is shown. Figure 5C Shows the expansion factor S BPS·SEBS Compare temperatures. Figure 5D Shows the expansion factor S SEBS·BPS Compare temperatures. Figure 5E Show the morphological types and the conditions they satisfy.

[0012] Figure 6A Izod impact strength is shown, and Figure 6B The tensile strength of several model systems as described herein is shown.

[0013] Figures 7A-7F Shown is PP / BPS[L]( Figure 7A )、PP / BPS / SEBS[SD]( Figure 7B )、PP / BPS[S]( Figure 7C )、PP / BPS / SEBS[CS]( Figure 7D )、PP( Figure 7E ) and PP / SEBS( Figure 7F ) versus normalized area (BDφ).

[0014] Figures 8A-8B show the TOM and POM of PP / BPS [L], respectively. Figures 8C-8D show the TOM and POM of PP / BPS / SEBS [SD], respectively, from an arrested crack after DN4PB.

[0015] Figures 9A-9B TOM and polarized optical microscopy (PO M) of PP / BPS[S] are shown, respectively. Figures 9C-9D The TOM and POM of PP / BPS / SEBS[CS] from arrested crack after DN4PB are shown, respectively.

[0016] Figure 10 TEM observation results of PP / BPS / SEBS[CS] showing self-arrested cracks after DN4PB test.

[0017] Figures 11A-11B The TOM and POM of PP are shown respectively. Figures 11C-11D The TOM and POM of PP / SEBS from arrested cracks after DN4PB are shown, respectively.

[0018] Figure 12 Schematic diagram showing possible toughening mechanisms.

[0019] Figures 13A-13C Shown is a double-notched four-point bending specimen ( Figure 13A ) and fracture surface analysis ( Figure 13B ) and damage area observation ( Figure 13C ) to study the toughening mechanism.

[0020] Figure 14 Shown are the effects of SEBS rubber and processing temperature on morphology.

[0021] Figures 15A-15B TEM images of the 8 phr / 230°C system are shown.

[0022] Figure 16 The complex viscosity is shown as a function of angular frequency.

[0023] Figure 17 Cole-Cole plots are shown for pure polymers and LLDPE / BPS / SEBS blend systems.

[0024] Figure 18 Representative engineering stress-engineering strain plots are shown.

[0025] Figure 19 Notched Izod impact strength at -37°C is shown.

[0026] Figures 20A-20D OM images of the crack tip damage area under bright field (left) and crossed polarizers (right) are shown: (FIGS. 20A-20B) 8 phr / 230°C and (FIGS. 20C-20D) 8 phr / 185°C.

[0027] 21A-2ID show SEM analysis of fracture surfaces of (FIG. 21A) LLDPE; (FIG. 21B) 8 phr / 185°C; (FIG. 21C) and (FIG. 21D) 8 phr / 230°C.

[0028] Figures 22A-22Z TEM images of experimental compositions are shown. The red arrows indicate the brominated flame retardant, while the blue arrows indicate the thermoplastic elastomer. Specific compositions are provided in Example 5.

[0029] Additional advantages of the present invention will be set forth in part in the description that follows and in part will be obvious from the description, or may be learned by practice of the present invention. The advantages of the present invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It should be understood that both the foregoing summary and the following detailed description are exemplary and explanatory only and do not limit the invention as claimed. DETAILED DESCRIPTION

[0030] The present disclosure provides flame-retardant plastic compositions, methods for preparing the flame-retardant plastic compositions, and articles comprising the flame-retardant plastic compositions. The flame-retardant plastic compositions of the present disclosure may be advantageous because they may improve fracture toughness. While not intending to be bound by theory, the toughening mechanism may include promoting crack initiation / shear banding. Additional features of the present disclosure may be provided below and in the Examples.

[0031] In one aspect, the flame retardant plastic composition can be used in articles such as molded parts for housings or connectors or circuit boards for electronic devices, various automotive applications such as engine compartment parts, seats, insulation materials and interior components, and residential applications such as insulation materials, carpets and wall coverings. In another aspect, the article can be a covering for cables and / or wires. In yet another aspect, the disclosed articles can be used in textiles and adhesives.

[0032] In one aspect, the flame retardant plastic composition may include a polymer component and a brominated flame retardant. The brominated flame retardant may be composed of one or more particles, wherein the one or more particles may be at least partially encapsulated by a thermoplastic toughening agent. The flame retardant plastic composition may include one or more particles that are not encapsulated by a thermoplastic toughening agent. The flame retardant plastic composition may include particles whose degree of encapsulation varies from complete encapsulation to no encapsulation. As an alternative or supplement to the above, one or more clusters comprising two or more particles may include varying degrees of encapsulation. Therefore, aspects of the present disclosure provide flame retardant plastic compositions that can be very complex because a single particle may be encapsulated to a certain extent or completely, a cluster of two or more particles may be encapsulated to a certain extent or completely, a single particle is not encapsulated, and a cluster of particles is not encapsulated. In one aspect, the weight percentage of the particles and / or particle clusters that can be at least partially encapsulated can be about 1 weight % to 100 weight %, about 5 weight % to 90 weight %, about 15 weight % to 75 weight %, or 30 weight % to 50 weight % of the total weight of the particles and / or particle clusters.

[0033] In one aspect, the one or more particles of the brominated flame retardant can be present in one or more of the following forms: (i) a plurality of particles that are individually partially encapsulated by a thermoplastic toughening agent, (ii) a plurality of particles that are individually completely encapsulated by a thermoplastic toughening agent, (iii) a plurality of clusters of two or more particles, wherein a single cluster in the plurality of clusters as a whole is partially encapsulated by a thermoplastic toughening agent, (iv) a plurality of clusters of two or more particles, wherein a single cluster in the plurality of clusters as a whole is completely encapsulated by a thermoplastic toughening agent, or (v) any combination thereof.

[0034] In any of these aspects, one or more particles at least partially encapsulated by a thermoplastic toughening agent have a core-shell structure in which the thermoplastic toughening agent forms a shell or a portion of a shell and the brominated flame retardant forms a core. In one aspect, the shell layer of the core-shell structure has an average thickness of from about 5 nm to about 10 μm, from about 5 nm to about 1 μm, from about 5 nm to about 200 nm, from about 100 nm to about 200 nm, or from about 5, 10, 15, 20, 25, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, or about 1000 nm (1 μm), or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In any of these aspects, the ratio of the average thickness of the shell layer to the average length in at least one dimension of the core layer of the core-shell structure is from about 0.05:1 to about 0.25:1, from about 0.05:1 to about 0.1:1, from about 0.1:1 to about 0.2:1, or about 0.05:1, 0.1:1, 0.15:1, 0.2:1 or about 0.25:1, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values.

[0035] In one aspect, and without wishing to be bound by theory, the thermoplastic toughening agent provides good dispersion of the brominated flame retardant in the polymer component and can coat the brominated flame retardant particles with sufficient thickness to convert the brominated flame retardant into toughened particles. The thermoplastic toughening agent can additionally act as a compatibilizer, as further described below. In one aspect, and without wishing to be bound by theory, the toughening agent acts as an interface between the brominated flame retardant and the polymer component.

[0036] In one aspect, the polymer component can be selected from polystyrene, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), ultra low density polyethylene (ULDPE), medium density polyethylene (MDPE), polypropylene (PP), polymethylpentene (PMP), polybutene-1 (PB-1), ethylene-octene copolymer, stereoblock PP, olefin block copolymer, propylene-butane copolymer, polyisobutylene (PIB), poly(α-olefin), ethylene propylene rubber (EPR), ethylene propylene diene monomer rubber (EPDM rubber), high density polyethylene (HDPE), ultra high density polyethylene (UHDPE), polyamide, polyester, styrenic polymers or copolymers, crosslinkable or crosslinked polyethylene (PEX or XLPE), or any combination thereof.

[0037] In some aspects, when the polymer component is or includes a polyamide, the polyamide can be selected from nylon 6,6; nylon 6; nylon 6,10; nylon 11; nylon 6,12; nylon 12; nylon 6,9; nylon 4,6: poly(m-phenylene isophthalamide); poly(p-phenylene terephthalamide); copoly(p-phenylene terephthalamide / d,4'-diphenylether terephthalamide); PA66 / 6, PA6T, PA9T, PA10T, PA4T, poly(m-xylene sebacamide), poly(m-xylene adipamide), copolymers thereof, or any combination thereof. In another aspect, when the polymeric component is or includes a polyester, the polyester can be selected from polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), poly(cyclohexylene dimethylene terephthalate) (PCT), polylactic acid (PLA), polycaprolactone (PCL), polyethylene terephthalate glycol (PETG), polycyclohexylene dimethylene terephthalate (PCTG), or any combination thereof. In still another aspect, when the polymeric component is or includes a styrenic polymer or copolymer, the styrenic polymer or copolymer can be selected from poly(styrene-co-acrylonitrile) (SAN), poly(acrylonitrile-co-butadiene-styrene) (ABS), or any combination thereof. In one aspect, the polymeric component is polypropylene, polystyrene, linear low density polyethylene (LLDPE), or ethylene-1-octene copolymer.

[0038] In another aspect, the brominated flame retardant can be selected from 1,2-bis(pentabromophenyl)ethane, brominated polystyrene, ethylene-bis-tetrabromophthalimide, decabromodiphenyl ether, brominated polystyrene; poly(bromostyrene), polyvinyl bromide, polyvinylidene bromide, poly(2-bromoethyl methacrylate), poly(2,3-dibromopropyl methacrylate), poly(methyl-a-bromoacrylate), brominated butadiene styrene copolymer, or any combination thereof.

[0039] In one aspect, the thermoplastic toughening agent can be a thermoplastic elastomer, such as for example styrenic block copolymer, thermoplastic polyurethane, acrylonitrile-butadiene rubber, acrylic elastomer, copolyester elastomer, thermoplastic polyether ester elastomer (TPEE), thermoplastic amide ether elastomer (TAEE), chlorinated rubber, ionomer, thermoplastic vulcanizate or its any combination. In one aspect, when the thermoplastic toughening agent is or when comprising acrylonitrile-butadiene rubber, acrylonitrile-butadiene rubber can be hydrogenated nitrile rubber. In another aspect, when the thermoplastic toughening agent is or when comprising a styrenic block copolymer, the styrenic block copolymer can be selected from styrene-ethylene butylene-styrene block copolymer (SEBS), maleic anhydride grafted SEBS block copolymer, styrene-ethylene propylene-styrene block copolymer (SEPS) or its any combination. In one aspect, when the toughening agent is or includes SEBS, the SEBS has a ratio of styrene to ethylene and butylene of about 10:90 to about 70:30, about 20:80 to about 50:50, about 50:50 to about 70:30, or about 10:90, 20:80, 30:70, 40:60, 50:50, 60:40 or about 70:30, or a combination of any of the foregoing values, or a range covering any of the foregoing values. In another aspect, when the thermoplastic toughening agent is or includes a thermoplastic polyurethane, the thermoplastic polyurethane can be a polyester polyurethane, a polyether polyurethane or any combination thereof. In still another aspect, when the thermoplastic toughening agent is or includes an acrylic elastomer, the acrylic elastomer can be an ethylene acrylic acid terpolymer. In one aspect, when the thermoplastic toughening agent is or includes chlorinated rubber, the chlorinated rubber can be polychloroprene, chlorinated polyethylene copolymer or any combination thereof. In one aspect, and without wishing to be bound by theory, unlike the inventive compositions of the present application, some SEBS polymers do not encapsulate or partially encapsulate brominated flame retardants when mixed, and therefore not all mixed systems comprising SEBS and brominated flame retardants can be considered to satisfy the systems as disclosed herein.

[0040] In any of these aspects, the flame retardant plastic composition may further comprise a compatibilizer. In one aspect, the compatibilizer may be maleic anhydride grafted polypropylene.

[0041] In one aspect, the flame retardant plastic composition can comprise from about 65% to about 85% by weight of the polymer component, from about 65% to about 75% by weight of the polymer component, from about 70% to about 80% by weight of the polymer component, or about 65%, 70%, 75%, 80% or about 85% by weight of the polymer component, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In another aspect, the flame retardant plastic composition can comprise from about 5% to about 35% by weight of the brominated flame retardant, from about 15% to about 25% by weight of the brominated flame retardant, from about 20% to about 30% by weight of the brominated flame retardant, or about 5%, 10%, 15%, 20%, 25%, 30% or about 35% by weight of the brominated flame retardant, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values.

[0042] In some aspects, the flame retardant plastic composition disclosed herein may also include a synergist. On the other hand, the synergist may be antimony trioxide (Sb herein O or ATO) or another synergist. In yet another aspect, the flame retardant composition may include about 1 wt % to about 10 wt %, about 1 wt % to about 5 wt %, about 5 wt % to about 10 wt % or about 3 wt % to about 7 wt % Sb O or other synergists, or about 1 wt %, 2 wt %, 3 wt %, 4 wt %, 5 wt %, 6 wt %, 7 wt %, 8 wt %, 9 wt % or about 10 wt % Sb O or other synergists, any combination of the foregoing values, or the scope of any of the foregoing values.

[0043] In still another aspect, the flame retardant plastic composition can include from about 4 wt% to about 8 wt% of the thermoplastic toughening agent, from about 4 wt% to about 6 wt% of the thermoplastic toughening agent, from about 6 wt% to about 8 wt% of the thermoplastic toughening agent, or about 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, or about 8 wt% of the thermoplastic toughening agent, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In still another aspect, the flame retardant plastic composition can include from about 0% to about 2% by weight of a compatibilizer, from about 0.25% to about 0.5% by weight of a compatibilizer, from about 0.5% to about 1% by weight of a compatibilizer, or from about 0%, 0.25%, 0.5%, 0.75%, 1%, 1.25%, 1.5%, 1.75% or about 2% by weight of a compatibilizer, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In any of these aspects, the weight percentages are based on the total weight of the polymer components, the brominated flame retardant, the thermoplastic toughening agent, and, if present, the compatibilizer.

[0044] In another aspect, the flame retardant plastic composition may further comprise a filler, such as, for example, talc, calcium carbonate, AgO, ZnO, CaO, MnO, Al(OH)3, AlO(OH), Mg(OH)2, kaolinite, wollastonite, mica, glass beads, or any combination thereof.

[0045] In one aspect, the flame retardant plastic composition has a melt flow rate of about 7.5 to about 20 g / 10 min, or about 7.5, 10, 12.5, 15, 17.5, or about 20 g / 10 min, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values.

[0046] Also disclosed herein is an article comprising or made from the flame retardant plastic composition disclosed herein. In one aspect, the article has a flame retardant resistance of about 4 to about 7 kJ / m at 25°C. 2 , about 4 to about 6 kJ / m 2 , about 6 to about 7 kJ / m 2 , or about 4, 4.5, 5, 5.5, 6, 6.5, or about 7 kJ / m 2 , or a combination of any of the foregoing values, or a range covering any of the foregoing values. In another aspect, the article can have an Izod impact resistance of from about 6.5 to about 10.5 kJ / m at -37°C. 2 , about 6.5 to about 8.5 kJ / m 2 , about 7.5 to about 9.5 kJ / m 2 or about 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10 or about 10.5 kJ / m 2 , or any combination of the foregoing values, or ranges encompassing any of the foregoing values. In yet another aspect, the article can have an elongation at break of about 45% to about 600%, about 45% to about 100%, about 100% to about 300%, about 300% to about 600%, or about 45%, 100%, 150%, 200%, 250%, 300%, 350%, 400%, 450%, 500%, 550%, or about 600%, or any combination of the foregoing values, or ranges encompassing any of the foregoing values.

[0047] In one aspect, the article may have a thermal conductivity of about 0.9 MPa·m at 25°C. -1 / 2 About 1.2 MPa·m -1 / 2 , about 0.9 to about 1.1 MPa·m -1 / 2 , about 1.0 to about 1.2 MPa·m -1 / 2 , or about 0.9, 1.0, 1.1 or about 1.2 MPa·m -1 / 2, or a critical stress intensity factor of about 15 MPa to about 30 MPa, about 15 to about 20 MPa, about 20 to about 30 MPa, or about 15, 20, 25, or about 30 MPa, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In one aspect, the article has a tensile strength of about 1700 MPa to about 4300 MPa, about 1700 to about 2500 MPa, about 2500 to about 3500 MPa, about 3500 to about 4300 MPa, or about 1700, 2000, 2500, 3000, 3500, 4000, or about 4300 MPa, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In one aspect, the article has a notched Izod impact strength of about 80 J / m to about 1100 J / m, about 100 to about 400 J / m, about 400 to about 800 J / m, about 800 to about 1100 J / m, or about 80, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, or about 1100 J / m, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. In any of these aspects, the article can have a flammability rating of VO according to test method UL94.

[0048] Also disclosed herein are methods for preparing the disclosed flame retardant plastic compositions. In one particular aspect, the method comprises at least the steps of: (a) blending a polymer component, a brominated flame retardant, and a thermoplastic toughening agent to form a precursor mixture; and (b) extruding the precursor mixture at an elevated temperature.

[0049] On the other hand, step (a) and step (b) can be carried out by any method known in the art. In one aspect, step (a) and / or step (b) are carried out in a twin-screw extruder. On the other hand, the elevated temperature can be about 160°C to about 230°C, about 190°C to about 210°C, about 210°C to about 230°C for polyolefins or polystyrenes, or can be about 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, 220°C, 225°C or about 230°C, or a combination of any of the foregoing values, or a range encompassing any of the foregoing values. For PPA (polyphthalamide or high temperature nylon), the processing temperature can be about 160°C to about 345°C. In one aspect, the twin-screw extruder has a speed of about 60rpm to 500rpm. In another aspect, the design and operation of a twin-screw extruder encompass those methods and parameters known to those skilled in the art.

[0050] In some aspects, the flame retardant plastic composition can be prepared by blending the polymer components, the brominated flame retardant, and the thermoplastic toughening agent in a double-arm mixer.

[0051] In another aspect, the method comprises at least the steps of: (a) blending the polymer components and the brominated flame retardant to prepare an initial composition known to those skilled in the art as a masterbatch; and (b) mixing the masterbatch and a thermoplastic toughening agent to form a second final mixture; and (c) extruding the final mixture at an elevated temperature.

[0052] On the other hand, step (a), (b) and (c) can be carried out by any method known in the art. In one aspect, step (a), (b) and / or (c) are carried out in a twin screw extruder. On the other hand, the temperature of increase can be about 160 ℃ to about 230 ℃, about 190 ℃ to about 210 ℃, about 210 ℃ to about 230 ℃, or can be about 160 ℃, 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃, 200 ℃, 205 ℃, 210 ℃, 215 ℃, 220 ℃, 225 ℃ or about 230 ℃, or a combination of any of the foregoing values, or a scope of any of the foregoing values. In one aspect, the twin screw extruder has a speed of about 60 rpm. In another aspect, the design and operation of the twin screw extruder encompass those methods and parameters known to those skilled in the art.

[0053] In any of these methods, when a synergist is used (such as, for example, antimony trioxide), it can be added at any step during the mixing process.

[0054] Those skilled in the art of the disclosed compositions and methods will recognize that many modifications and other embodiments disclosed herein will benefit from the teachings presented in the foregoing description and the associated drawings. Therefore, it should be understood that this disclosure is not limited to the specific embodiments disclosed, and that such modifications and other embodiments are intended to be included within the scope of the appended claims. Those skilled in the art will recognize many variations and adaptations of the aspects described herein. These variations and adaptations are intended to be included within the teachings of this disclosure and are encompassed by the claims herein.

[0055] Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0056] As will be apparent to those skilled in the art after reading this disclosure, each individual embodiment described and illustrated herein has discrete components and features that may be readily separated or combined with the features of any other several embodiments without departing from the scope or spirit of the disclosure.

[0057] Any described method may be performed in the order of events recited, or in any other order that is logically feasible. That is, unless expressly stated otherwise, it is not intended that any method or aspect described herein be construed as requiring that its steps be performed in a specific order. Therefore, when a method claim does not expressly state in the claim or specification that the steps are to be limited to a specific order, no order is intended to be inferred in any respect. This applies to any possible non-express basis for interpretation, including matters of logic with respect to the arrangement of steps or operational flow, obvious meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification.

[0058] Although aspects of the disclosure may be described and claimed using specific legal categories, such as the system legal category, this is for convenience only, and those skilled in the art will understand that aspects of the disclosure may be described and claimed using any legal category.

[0059] It should also be understood that the terminology used herein is for the purpose of describing specific aspects only and is not intended to be limiting. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the disclosed compositions and methods belong. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the specification and the context of the relevant art, and should not be interpreted as idealized or overly formal unless explicitly defined herein.

[0060] Before describing the various aspects of the present disclosure, the following definitions are provided and shall apply unless otherwise indicated.Additional terms may be defined elsewhere in this disclosure.

[0061] definition

[0062] As used herein, "comprising" should be interpreted as indicating the presence of stated features, integers, steps or components as mentioned, but does not exclude the presence or addition of one or more features, integers, steps or parts thereof or groups thereof. In addition, each of the terms "by", "comprising", "comprises", "comprised of", "including", "includes", "included", "involving", "involves", "involved", and "such as" is used in its open, non-restrictive sense and is used interchangeably. In addition, the term "comprising" is intended to include instances and aspects encompassed by the terms "substantially consisting of" and "consisting of". Similarly, the term "substantially consisting of" is intended to include instances encompassed by the term "consisting of".

[0063] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a "polymer," "brominated flame retardant," or "article" includes but is not limited to a mixture or combination of two or more such polymers, brominated flame retardants, or articles, etc.

[0064] It should be noted that ratio, concentration, amount and other numerical data can be expressed in range format in this article. It should be further understood that the endpoints of each range are meaningful relative to another endpoint and independently of another endpoint. It should also be understood that multiple values ​​are disclosed herein, and each value is also disclosed as "about" the specific value in addition to the value itself. For example, if the value "10" is disclosed, "about 10" is also disclosed. Scope can be expressed as from "about" a specific value and / or to "about" another specific value in this article. Similarly, when a value is expressed as an approximate value by using the antecedent "about", it will be understood that the specific value forms another aspect. For example, if the value "about 10" is disclosed, "10" is also disclosed.

[0065] When expressing a range, additional aspects include from one specific value and / or to another specific value. For example, when the stated range includes one or both of the limits, the present disclosure also includes a range that excludes any one or both of those included limits, such as the phrase "x to y" includes a range from 'x' to 'y' and a range greater than 'x' and less than 'y'. A range can also be expressed as an upper limit, such as 'about x, y, z or less', and should be interpreted as including the specific range of 'about x', 'about y' and 'about z' and the range of 'less than x', 'less than y' and 'less than z'. Similarly, the phrase 'about x, y, z or more' should be interpreted as including the specific range of 'about x', 'about y' and 'about z' and the range of 'greater than x', 'greater than y' and 'greater than z'. In addition, the phrase "about 'x' to 'y'" (wherein 'x' and 'y' are numerical values) includes "about 'x' to about 'y'".

[0066] It should be understood that this range format is used for convenience and brevity and should therefore be interpreted flexibly to include not only the values ​​explicitly recited as the limits of the range, but also all individual numbers or subranges encompassed within the range, as if each value and subrange were explicitly recited. For illustration, a numerical range of "about 0.1% to 5%" should be interpreted to include not only the explicitly recited values ​​of about 0.1% to about 5%, but also the individual values ​​(e.g., about 1%, about 2%, about 3%, and about 4%) and subranges within the specified range (e.g., about 0.5% to about 1.1%; about 5% to about 2.4%; about 0.5% to about 3.2% and about 0.5% to about 4.4% and other possible subranges).

[0067] As used herein, the terms "about," "approximately," "at or about," and "substantially" mean that the amount or value in question can be an exact value or a value that provides an equivalent result or effect as described in the claims or taught herein. That is, it should be understood that amounts, dimensions, formulations, parameters, and other quantities and characteristics are not and need not be exact, but can be approximate and / or larger or smaller as necessary to reflect tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art, so that an equivalent result or effect is achieved. In some cases, it is not possible to reasonably determine a value that provides an equivalent result or effect. In such cases, it should generally be understood that, as used herein, unless otherwise indicated or inferred, "about" and "at or about" are intended to indicate a nominal value with a ±10% variation. In general, an amount, dimension, formulation, parameter, or other quantity or characteristic is "about," "approximately," or "at or about," regardless of whether such an explicit statement is made. It should be understood that when "about," "approximately," or "at or about" is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless otherwise specifically stated.

[0068] As used herein, the term "effective amount" refers to an amount sufficient to achieve the desired modification of a physical property of a composition or material. For example, an "effective amount" of a thermoplastic toughening agent refers to an amount sufficient to achieve the desired improvement in a property regulated by a formulation component, such as an amount to achieve the desired level of encapsulation and / or compatibilization of the brominated flame retardant in the polymer phase. The specific level, expressed as wt % in the composition, required as an effective amount will depend on a variety of factors, including the amount and type of polymer components, the amount and type of thermoplastic toughening agent, the amount and type of brominated flame retardant, and the end use of the article to be made using the composition.

[0069] As used herein, the terms "optional" or "optionally" mean that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.

[0070] "Thermoplastic" polymers become plastic, pliable, or moldable when heated and resolidify upon cooling. The temperature at which thermoplastic polymers soften can vary depending on the polymer composition. Thermoplastic polymers exhibit no change in chemical properties or composition upon heating and resolidification. Thermoplastic compositions can be processed using a variety of methods, including extrusion, injection molding, thermoforming, and the like.

[0071] As used herein, an "elastomer" is a polymer that exhibits elastic or rubber-like properties and is able to return to its original shape after being stretched or subjected to another applied stress. Elastomeric polymers have a molecular structure that is disordered and non-crystalline at rest. A "thermoplastic elastomer" is a thermoplastic polymer that also exhibits elastomeric properties.

[0072] "Test method UL94" refers to a test method developed by Underwriters Laboratories (UL) in the United States, which is intended to serve as a preliminary indication of the acceptability of a plastic for use as part of an article with respect to flammability. To achieve a V-0 flammability rating, for example, after two ten-second flames are applied to the test rod, combustion of the article must cease within ten seconds. There may be no flaming dripping.

[0073] Unless otherwise indicated, temperatures referred to herein are based on atmospheric pressure (ie, one atmosphere).

[0074] Now that aspects of the present disclosure have been described, generally speaking, the following examples describe some additional aspects of the present disclosure. Although aspects of the present disclosure are described in conjunction with the following examples and corresponding text and drawings, it is not intended that aspects of the present disclosure be limited to this description. On the contrary, it is intended to cover all alternatives, modifications, and equivalents included within the spirit and scope of the present disclosure.

[0075] Example

[0076] The following examples are presented to provide a complete disclosure and description of how the compounds, compositions, articles, devices and / or methods claimed herein are prepared and evaluated by one of ordinary skill in the art, and are intended to be purely exemplary of the present disclosure and are not intended to limit the scope of what the inventors consider to be their disclosure. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperatures, etc.), but some errors and deviations should be considered. Unless otherwise indicated, parts are by weight, temperatures are in ° C. or at ambient temperature, and pressures are equal to or near atmospheric pressure.

[0077] Example 1: Polypropylene system, materials and models

[0078] Materials and model systems

[0079] PP (grade name: Profax 6523, isotactic index ≥94, M w : 342,000 g / mol, PDI: 9.4) were obtained from LyondellBassel, and BPS (medium M w , research grade) was donated by Albemarle. The rubber used (grade name: SEBSG1652, styrene content: 30 wt.%, Mw: 85,000 g / mol, PDI: 1.2) was received from Kraton.

[0080] A total of six different model systems were prepared, as shown in Table 1. Several notes describing the specific model systems refer to PP / BPS[L] as a binary system of ‘large’ BPS particles dispersed in PP, PP / BPS / SEBS[Sd] as a ternary system of BPS and SEBS ‘separately dispersed’ in PP, PP / BPS[S] as a binary system of ‘small’ BPS particles dispersed in PP, and PP / BPS / SEBS[CS] as a ternary system of a ‘core-shell’ structure between BPS and SEBS in PP, based on their respective Figures 4A-4D Morphological observations in [ 1 ]. As a control system, PP was also extruded before being molded to give them the same thermal history as the other model systems. To achieve a UL94 V-0 rating for polyolefins, it is known that a total bromine content of approximately 18 to 19 wt.% is required. Therefore, the model system was formulated to have this total bromine content. The amount of SEBS was arbitrarily selected to be 4 wt.% to maximize encapsulation onto BPS and minimize modulus degradation.

[0081]

[0082] Extrusion, injection molding and compression molding

[0083] After manually blending PP, BPS pellets and rubber powder in a transparent zipper bag, all model systems were extruded in a twin-screw extruder (ThermoFisher Process 11, L / D=40) with a feeder (twin screw). The total amount of feed was 2 kg, and the amount collected from the extruder was 1.5 kg. The composition is shown in Table 1. Extrusion temperature indicates that all barrel zones (mold and zone 1-7) have a temperature of 190°C or 230°C, depending on each composition in Table 1. The twin-screw speed of the extruder and the single screw speed of the feeder are 60 RPM and 5 RPM respectively. After extrusion, the strands were cooled in a water bath and manually chopped. These chopped pellets were injection molded (Thermo Scientific HAAKE MiniJet Pro) or compression molded (PHI model PW-22). In each model system, the injection barrel was set to the same temperature as its extrusion temperature. During the cooling time of 15 seconds, the mold temperature and injection pressure (holding pressure) were 60° C. and 670 bar, respectively. Each model system for the SN3PB and DN4PB test specimens was compression molded from a mold having a cavity size of 127 mm x 60 mm x 6.4 mm at a pressure of 6 MPa at the same temperature as its extrusion temperature, and then rapidly cooled from a water bath.

[0084] Izod impact strength

[0085] Rectangular bar specimens (63.5 mm × 12.7 mm × 3.2 mm) were prepared from an injection molder under the processing conditions described in Section 2.2. A notch (radius: 250 μm) was machined and impact tested at room temperature (25°C) using a pendulum impact machine (Tinius Olson Model 66, impact velocity: 2.9 m / s) according to ASTM D256. The thickness and notch depth of each specimen were carefully measured using a micrometer (Mitutoyo Model 5431, resolution: 1 μm). Five specimens for each model system were measured and the average value was calculated.

[0086] tensile strength

[0087] Dog-bone tensile specimens (ASTM D638, Type IV) were prepared using the same injection molding conditions as the Izod impact specimens. Tensile testing was performed at room temperature (25°C) using a tensile load frame machine (Instron Model 5567, load cell: 5 kN) at a crosshead speed of 5 mm / min based on ASTM D638. The modulus, yield strength, and elongation at break of three specimens were measured and then averaged.

[0088] Critical energy release rate (G 1c )

[0089] As mentioned in section 2.1, eight rectangular specimens (127 mm x 12.7 mm x 6.4 mm) with a straight crack at the center of each model system were prepared by machining from compression molded plates. The straight crack consisted of a machined portion and a sharp crack portion. The sharp crack was generated using a new razor blade slid from an instrumented scratch machine in a linear progressive normal load increment (1 to 50 N). The razor blade sharpening length was similar for all specimens of 600 ± 50 μm and the machining notch length was generated differently so that each specimen had a different total initial crack length in the range of 0.3 ≤ a / W ≤ 0.7. The geometry of the test setup was single notch three-point bending (SN3PB) at an impact velocity of 2.9 m / s. Detailed information on the specimen and test geometry as well as the generation of the sharp crack is as follows. Figures 1A-2A As shown in the introduction.

[0090] The following equation is used to calculate the critical energy release rate (G Ic ).

[0091] According to the definition of flexibility and energy release rate,

[0092]

[0093] By combining Equation 1 and Equation 2,

[0094] U=G c BWφ (Equation 3)

[0095]

[0096] The variables used are defined as follows: P: load, U: fracture energy, C: compliance, B: sample thickness, a: initial crack length, W: sample width, : energy calibration factor, G c : Critical energy.

[0097] U t =U+U0 (Equation 5)

[0098] When the pendulum strikes the SN3PB specimen, the total energy U generated includes an additional energy term, U0, which does not dissipate energy in the new surface created by the fracture. U0 includes the kinetic energy of the fractured specimen as it flies out, the frictional energy between the specimen and the fixture, and acoustic energy. U0 is calculated by floating the fractured specimen into the fixture and striking it again, as shown in Figure 1D. The additional frictional energy between the fractured specimen and the auxiliary rod is assumed to be negligible.

[0099] In order to obtain an accurately calibrated energy factor for the generalized SN3PB geometry, Guinea's load point compliance function is applied, which is independent of any span length.

[0100] In order to obtain the energy calibration factor, the flexibility function needs to be differentiated. The derivative term (dC / dα) in the energy calibration factor () is calculated using Wolfram Mathematica software based on the flexibility function in Table 2. Figure 2B As shown, the total initial crack length a of each specimen was measured by a handheld mobile microscope (Dinolite AM311S). Once the fracture energy values ​​(U) of the eight samples of each model system are plotted against their normalized area (BW), the slope is the critical energy release rate (G Ic ).

[0101]

[0102] Qualitative toughening mechanism test

[0103] The specimen preparation for the double-sided notched four-point bending (DN4PB) test is the same as that for the SN3PB test. One difference is that the specimen has two sharp cracks, as shown in Figure 3A. The instrument scratch machine creates two sharp cracks that are almost but not exactly the same. During the impact impact process of the four-point bending, even if one crack expands and the other stops, the two cracks will have similar damage process zones. A foam-type damper (thickness: 3 mm) is used to minimize the asymmetric impact from the two-point contact between the impact head and the specimen as shown in Figure 3B. This technique can be used to observe subcritical fracture features, which represent phenomena before crack extension. The fracture observation results are first examined using a petrographic thin section technique in an optical microscope (OM) to view a global view of the damage zone, and then a transmission microscope (TEM) is used to examine the microscopic damage (or toughening) features. A diamond saw (Buhler ISOMET 1000) is used for mid-plane sectioning. One side of the mid-plane section is embedded in epoxy resin and attached to a glass slide and carefully polished to 80 μm for optical microscope observation in Figure 3D. The other side was embedded in an epoxy resin block for TEM observation.

[0104] Light microscopy

[0105] After petrographic preparation as shown in Figure 3D, the polished samples attached to glass slides were imaged in an optical microscope (Olympus BX60) in bright field (TOM) and in transmission mode under crossed polarizers (POM). No additional filters were applied.

[0106] Staining procedure and TEM microscopy

[0107] A pre-staining method was used to distinguish the different phases. The styrene phase in SEBS rubber is known to stain with RuO₄. The embedded block surface was trimmed and cryo-polished at -60°C using a diamond knife to prevent smearing. The cryo-polished blocks were then stained with a vapor phase of a 2% RuO₄ aqueous solution at ambient temperature for 4 hours. The staining solution was prepared using ruthenium(III) chloride hydrate (RuCl₃ x HO) and a 5.25% sodium hypochlorite aqueous solution in a screw-capped glass jar. After staining, the embedded blocks were placed in deionized water overnight and then sectioned to allow residual RuO₄ to dissipate from the sample. The stained block surface was thin-sectioned to a thickness of 120 nm using a diamond knife with a water boat, and several thin sections were transferred to copper grids in a microtome (Leica EMUC7 Ultramicrotome) at ambient temperature. TEM images were processed using a JEOL 1200X microscope with an electron beam voltage of 100 keV. The BPS particle size for each model system was averaged from three different TEM images.

[0108] Surface energy measurement

[0109] The surface energy analysis of BPS was performed using an iGC surface energy analyzer, SEA (surface measurement system), and the data values ​​were analyzed using the SEA analysis software package. The measurement steps are briefly summarized here, but the detailed method can be found in several references. Approximately 150 mg of BPS powder sample was loaded into a separate silanized glass column. The total surface area (in nm) of the powder sample was measured with probe molecules, and then different amounts of probe molecules were injected into the column. The normalized surface area is expressed as n / nm. In the following steps, after readjusting with helium before each experiment, different series of probe molecules were injected into the column to measure retention time. By using the James and Martin correction factor, the retention time of the probe molecules interacting with the powder material in the iGC column measured was converted to net retention volume. Gibbs adsorption free energy was calculated by substituting the net retention volume into Henry's law (Henry's law), where the adsorption free energy is related to the adhesion work on the powder material surface. Detailed information is shown in the following literature. The dispersion surface energy (γ d ) and polar surface energy (γ p). All experiments were performed at 30 °C. Methane gas was used for dead volume correction. For the determination of the dispersion and polar terms of the surface energy, the method of Dorris and Gray and the Good-van Oss-Chaudhury model were used. The resulting dispersion and polar terms of the surface energy of BPS are presented in Table 3. γ10, γ50, and γ90 represent the values ​​of the area portion corresponding to the coverage along the lower edge of the surface energy diagram using an exponential decay function, where the distribution of the surface energy is attributed to the defects and flaws of the surface. The γ50 value is widely chosen as a representative value of the surface energy. The -dγ / dT value of BPS is calculated based on the linear approximation of the density value diagram in Equation 6.

[0110] γ(T)=γ(298)[ρ(T) / ρ(298)] 4 (Equation 6)

[0111] The density values ​​of BPS measured with silicone oil in a pycnometer at temperatures of 25°C, 40°C, 50°C, 60°C, and 70°C were 2.22, 2.20, 2.18, 2.17, and 2.16, respectively.

[0112]

[0113]

[0114]

[0115] Example 2: Polypropylene System, Results and Discussion

[0116] Morphological analysis

[0117] The glass transition (T g ) is in the range of 163°C to 182°C. The processing temperatures of 190°C and 230°C are both higher than T g . Figure 4A and Figure 4C The first clear observation, shown in Figure 1, is the size variation of BPS particles at different temperatures in the PP / BPS binary system. It can be seen that due to the reduced viscosity of BPS at high processing temperatures, mixing occurs more readily, which likely induces better kinetic dispersion. This observation confirms that PP and BPS are immiscible polymer blends. Polymers that are miscible with BPS are rare.

[0118] The ternary polymer blend system of PP, BPS and SEBS not only has the difference in BPS particle size, but also Figure 4B and Figure 4DThere are also clear morphological differences in the samples. At a processing temperature of 190 °C, BPS and SEBS are dispersed separately. On the other hand, in addition to the good dispersion of smaller BPS particles, the BPS particles are also encapsulated by the SEBS rubber. For the samples dyed with RuO4, the darker phase is SEBS due to the higher electron density of ruthenium relative to bromine. In order to further investigate the root cause of the morphological differences, the thermodynamic extension theory was applied. Since Hobbs proposed the modified Harkins equation, the morphological estimation made by this model is in good agreement with the experimental observations of the ternary polymer blends. The total surface energy of the selected materials of BPS, PP and SEBS and their dispersion and polar terms are shown in Tables 3 and Figure 4A Each interface energy (γ ij ) is calculated using the harmonic equation shown below.

[0119]

[0120] S ik =γ kj -γ ij -γ ik (Equation 8)

[0121] where i, j and k represent the components BPS, PP or SEBS; γ i : surface energy of I; γ ij : the interface energy between i and j; and S ik : Expansion coefficients of i and k to j.

[0122] When the expansion factor S ik satisfy Figure 5E Under certain conditions, the two secondary phases establish their stable positions. For this concept to work, some important prerequisites must be met. The polymers must be immiscible, and the quenching must be rapid enough to preserve the morphology of the molded sample. Our samples meet both of these conditions.

[0123] The dispersion and polar components of the surface energy of BPS are shown in Tables 3 and Figures 2A-2B γ10, γ50, and γ90 represent the values ​​corresponding to the area fraction under the surface energy map using an exponential decay function. The distribution of surface energy depending on the fractional surface coverage is caused by imperfections (such as defects) on the BPS surface. γ50 was selected as a representative value for the expansion coefficient equation for morphological estimation. The expansion coefficient S BPS·SEBS remains negative over the entire temperature range. On the other hand, the expansion coefficient S SEBS·BPS The value of α becomes positive at temperatures above 220 °C, which means that the core-shell morphology is thermodynamically favorable. This estimate is consistent with the results of TEM observations.

[0124] Izod impact and tensile behavior

[0125] Izod impact strength is a simple and rapid screening tool for comparing relative rankings of systems with better impact properties. The PP / BPS / SEBS[SD] system showed no improvement over the PP / BPS[S] system. One possible scenario is that crack propagation is controlled by large particles either penetrating weak interfaces or splitting rigid particles. On the other hand, PP / BPS / SEBS[CS] showed significant improvement over the other three model systems containing BPS, and its impact strength approached that of PP / SEBS. The rubber-coated BPS particles appear to act as a toughening agent.

[0126] In tensile behavior, samples containing large BPS, such as PP / BPS[L] and PP / BPS / SEBS[SD], began to fracture immediately after yielding. PP / BPS[S] and PP / BPS / SEBS[CS], exhibited necking and expansion after yielding, while PP / BPS[L] and PP / BPS / SEBS[SD] showed no necking. Interestingly, PP / BPS / SEBS[SD] and PP / BPS / SEBS[CS] exhibited significantly different moduli despite the same amount of SEBS formulated into them. The modulus of PP / BPS / SEBS[CS] was even lower than that of PP and comparable to that of PP / SEBS. Therefore, under these uniaxial far-field stress conditions, the matrix is ​​primarily affected at the interface with SEBS, not BPS, indirectly demonstrating that the rubber-encapsulated BPS particles behave like rubber particles. Based on their analytical studies, Matonis et al. confirmed that when the coated rubber thickness exceeds approximately 4% of the rigid particle radius, the modulus approaches that of a binary polymer system containing only rubber.

[0127]

[0128] Critical energy release rate (G 1c ) and toughening mechanisms

[0129] Izod and Charpy impact strengths have several limitations due to geometric dependencies such as notch radius and length, span length, specimen thickness, etc. Therefore, many efforts have been made to obtain geometry-independent fracture toughness parameters under impact conditions. The critical energy release rate is the intrinsic fracture toughness value based on linear elastic fracture mechanics [LEFM]. The systems dominated by large particles (PP / BPS[L] and PP / BPS / SEBS[SD]) show even lower fracture toughness than the PP system. This means that in those large particle systems, the resistance to the propagation of sharp crack tips is so low that the material behaves more brittle than the matrix polymer. In Figures 8A and 8C, the crack penetrates the BPS particles and there is no crack suppression mechanism, which is a typical brittle failure of the rigid particle incorporated system. In Figure 7CThe PP / BPS[S] system also shows a significant decrease in fracture toughness. Figure 9A and Figure 11A As shown in the figure, the degree of suppression of cracking, which is a typical damage behavior in front of the crack tip of thermoplastic materials, is even stronger than that of PP. However, PP / BPS / SEBS[CS] shows a significant improvement in fracture toughness. This can be attributed to the generation of shear bands formed by large-scale cracking. Shear yielding will be triggered due to the release of triaxial stress constraints through volume expansion. Here, large-scale cracking is the main trigger for volume expansion. In order to clearly investigate the micro-toughening mechanism of PP / BPS / SEBS[CS], TEM ( Figure 10 ). Direct evidence was found that rubber-coated BPS particles initiated and stabilized large-scale cracking. As the volume expanded, increasing stresses were generated, leading to the appearance of shear bands. Therefore, the proposed mechanism is as follows Figure 12 Although the rubber-encapsulated BPS does act as a toughening agent, its toughening mechanism is slightly different. Figures 11C-11D As shown in Figure 2, SEBS rubber first undergoes cavitation and then undergoes volume expansion as it cracks, followed by a shear band mechanism. Similar mechanisms can be found in the literature.

[0130] in conclusion

[0131] We successfully prepared BPS particles encapsulated with SEBS rubber by carefully selecting processing conditions. The morphological differences between the core-shell structure and the independent dispersed structure in the ternary polymer blends of PP, BPS, and SEBS were consistent with theoretical estimation analysis using thermodynamic extension theory. SEBS rubber was confirmed to significantly improve the fracture toughness by encapsulating the rigid BPS particles and emulsifying the BPS dispersion as a compatibilizer. Therefore, the proof of concept that the rubber-coated BPS acts as a toughening agent was verified. The toughening mechanism includes the promotion of crack initiation / shear banding. Therefore, the rubber-coated BPS acts as both a toughening agent and a compatibilizer.

[0132] Example 3: LLDPE system, materials and models

[0133] Material

[0134] LLDPE (grade: Petrothene GA564189) was purchased from LyondellBasell Industries. BPS was provided by Albemarle Corporation. SEBS rubber (grade: Kraton FG 1901, maleic anhydride grafted SEBS) was generously donated by Kraton Corporation. All were used as received in pellet form.

[0135] Sample preparation

[0136] The polymer blend compositions and processing conditions are described in Table 6. The LLDPE / BPS had a fixed weight ratio of 75:25, with varying amounts of SEBS rubber added as a compatibilizer. For each composition, all pellets were added together in a single step to a twin-screw Haake mixer (Rheocord system 40, Haake Buchler). Each composition was blended at a fixed screw speed of 60 rpm for 7 minutes at a constant temperature.

[0137]

[0138]

[0139] The blended resins were then injection molded into tensile bars (ASTM D638 Type V) and rectangular bars (63.5 mm × 12.7 mm × 3.2 mm) for mechanical testing. Injection molding was performed using a Haake MiniJet Pro Piston Injection Molder (ThermoFisher Scientific Inc.) with a barrel temperature of 190°C, a mold temperature of 60°C, and an injection pressure of 680 bar.

[0140] Characterization

[0141] form

[0142] An Olympus BX60 optical microscope (OM) was used to observe the microscale morphology. The sample (5 mg) was placed between two glass slides and then hot-pressed into a thin film at 190°C for OM observation.

[0143] Transmission electron microscopy (TEM) images were obtained using a JEOL JEM-1200 operated at 100 keV for nanoscale morphology observation.Ultrathin sections with a thickness of 100 nm were prepared at cryogenic temperature using a Reichert-Jung Ultracut E ultramicrotome with a diamond knife.

[0144] Rheology

[0145] Rheological measurements were performed using a TA Instruments ARES-G2 rheometer with a 25 mm diameter parallel plate. Strain sweep measurements were first performed to determine the linear viscoelastic region, followed by frequency sweeps from 100 rad / s to 0.1 rad / s at 230°C under nitrogen.

[0146] Mechanical testing

[0147] Tensile properties were measured using an Instron universal testing machine. Tensile bars (ASTM D638 Type V) were subjected to uniaxial tension at a crosshead speed of 25.4 mm / min, and the gauge length change was monitored using an extensometer. Engineering stress-engineering strain plots were used to calculate modulus, yield strength, and elongation at break. Secant modulus was measured at 1% strain. At least five specimens were tested for each system, and the average value was reported.

[0148] Notched Izod impact tests were performed at -37°C using a Tinius Olsen plastics impact tester according to ASTM D256. A 22.6J pendulum weight was used. V-notch specimens (63.5mm × 12.7mm × 3.2mm) were first preconditioned at -37°C for 1 hour in an environmental chamber (Standard Environmental System, Inc.) attached to an impact tester. Once the environmental chamber was opened, the specimens were immediately struck with a pendulum weight to minimize the temperature rise of the specimens. The absorbed energy was used to calculate the impact strength. At least five specimens were tested for each system and the average value was reported.

[0149] Characterization of toughening mechanism

[0150] like Figures 13A-13C Double-notch four-point bending (DN-4PB) specimens were prepared as shown. First, a notch of 2.54 mm in depth was cut into the specimen using a notch cutter, and then two almost identical sharp pre-cracks were struck using a fresh razor blade cooled in liquid nitrogen. The DN-4PB Charpy impact test was carried out at -37°C on a pendulum impact tester with a double-head impactor. One pre-crack eventually broke, and the other survived. The surviving crack was cut into thin sections for observation of the damaged area under bright field and orthogonal polarization OM, while the fracture surface was studied using a JEOL JSM-7500F field emission scanning electron microscopy (SEM) operated at 5.0 kV.

[0151] Example 4: LLDPE System, Results and Discussion

[0152] form

[0153] Figure 14Figure 3 shows the effect of SEBS addition and processing temperature on morphology. When LLDPE and BPS are blended at 185°C, the particle size of the dispersed BPS phase in this non-compatibilized system can be as large as 40μm. The shape of the dispersed BPS phase appears to be irregular rather than spherical. The addition of SEBS slightly improves the dispersibility of BPS, but its particle size is still as large as 10-20μm. When LLDPE and BPS are blended at a higher temperature of 230°C, the BPS particles become uniformly dispersed with a particle size of less than 5μm. When they are blended at 230°C and SEBS rubber is added, the dispersion state is further improved, and the BPS particle size becomes too small to be detected under OM. Further morphological studies using TEM on the well-dispersed 8phr / 230°C system show that the BPS particle size can be reduced to less than 0.5μm ( Figures 15A-15B ).

[0154] The combined effect of adding SEBS rubber and selecting the appropriate processing temperature results in a significant improvement in the dispersion of BPS in LLDPE. It has been reported that the viscosity ratio can significantly affect the morphology of immiscible polymer blends. If the viscosity ratio is close to 1, fine dispersions are usually achieved and better mechanical properties can be obtained. When the LLDPE / BPS is at a typical processing temperature of LLDPE such as 185°C (<T of BPS), the dispersion is very fine. cf ), BPS does not melt completely. But if LLDPE / BPS are melt mixed at 230°C, the viscosity ratio is 2.3, which is closer to 1 (Table 7). This viscosity ratio of 2.3 contributes to a significant improvement in dispersion. Higher processing temperatures (>230°C) were not studied due to LLDPE degradation. Once the optimal processing temperature is determined, the addition of SEBS copolymer can further help improve the compatibility between the LLDPE phase and the BPS phase because the SEBS copolymer has ethylene / butylene and styrene chain segments that have good affinity for the LLDPE phase and the BPS phase, respectively. The SEBS copolymer is present at the interface between the LLDPE phase and the BPS phase and forms a shell layer that covers the dispersed BPS particles, thereby contributing to the formation of a core-shell structure ( Figures 15A-15B ).

[0155]

[0156] Rheology

[0157] The effects of different morphologies on the rheological behavior due to different processing temperatures and SEBS rubber loadings were investigated. The complex viscosities of these systems as a function of angular frequency are shown in Figure 16The addition of BPS to LLDPE increases viscosity in the low-frequency region due to the higher viscosity of BPS. Even for the poorly dispersed system blended at 185°C, the addition of SEBS rubber slightly increases viscosity due to slightly reduced BPS particle size and, consequently, greater interfacial area in the 4phr / 185°C and 8phr / 185°C systems compared to the 0phr / 185°C system. The viscosity increase in the low-frequency region becomes more pronounced in the well-dispersed system blended at 230°C. The well-dispersed 8phr / 230°C system exhibits the highest viscosity in the low-frequency region. This increase in viscosity due to the compatibilization effect of SEBS rubber can be attributed to three factors: reduced BPS droplet size, a narrower BPS particle size distribution, and, most importantly, stronger interfacial interactions between the BPS particles and the LLDPE matrix phase. The rheological response is consistent with earlier morphological observations.

[0158] The Cole-Cole plot also shows distinct relaxation characteristics between poorly dispersed and well dispersed systems ( Figure 17 ). A polymer with a single relaxation process will appear as a semicircle in the Cole-Cole plot, while a second peak indicates the presence of a different relaxation mechanism. The poorly dispersed 4phr / 185°C and 8phr / 185°C systems show two peaks located between the characteristic relaxation peaks of neat LLDPE and neat BPS. This indicates that 4phr / 185°C and 8phr / 185°C are only partially compatibilized to a very limited level. On the other hand, the well-dispersed 4phr / 230°C and 8phr / 230°C systems show only a single semicircle, indicating that they have a single relaxation mechanism due to effective compatibilization. Compared to 4phr / 230°C, 8phr / 230°C shows a slight rightward shift of the relaxation peak, indicating longer relaxation times, which may be due to more interfacial entanglement when more SEBS rubber is added. Rheological measurements indicate that morphological homogeneity and interfacial interactions can be significantly enhanced in well-compatibilized systems such as 8phr / 230°C.

[0159] Mechanical properties

[0160] The engineering stress-engineering strain diagram is shown in Figure 18Well-dispersed systems blended at 230°C consistently exhibited higher tensile yield stress and better elongation at break than their less-dispersed counterparts blended at 185°C (Table 8). Generally speaking, incorporating BPS into LLDPE results in an increase in modulus due to the higher stiffness of BPS. However, further addition of the softer SEBS rubber phase to the LLDPE / BPS mixture gradually decreases the modulus. The modulus at 0 phr / 230°C is nearly identical to that at 0 phr / 185°C, and the normalized crystallinity of the LLDPE is approximately 23% for all systems. These facts suggest that processing at 230°C does not result in significant degradation of either polymer. Interestingly, both 4 phr / 230°C and 8 phr / 230°C exhibit lower moduli than their counterparts blended at 185°C. Given the lack of significant polymer degradation or differences in crystallinity, this can only be explained by differences in their morphology. In the well-dispersed 4phr / 230°C and 8phr / 230°C systems, the SEBS rubber will encapsulate the rigid BPS particles and form a core-shell structure with a BPS core and a SEBS shell, while some SEBS chains will penetrate into the BPS core phase and mix with it. The modulus of the BPS core will be softened by these SEBS polymer chains, resulting in a slightly lower overall modulus. It is also possible that the core-shell morphology in which SEBS is wrapped around BPS may cause the SEBS-wrapped BPS to behave like rubber, and the contribution of the rigid BPS core to stiffness is masked by the soft SEBS shell, which reduces the overall modulus. On the other hand, in the poorly dispersed 4phr / 185°C and 8phr / 185°C systems, no core-shell structure is formed, and most of the SEBS rubber particles remain in the LLDPE phase (Figure 21B). Therefore, the rigid BPS particles are not softened by the SEBS rubber, resulting in the poorly dispersed systems exhibiting a slightly higher modulus than their well-dispersed counterparts.

[0161]

[0162] The impact resistance in cold environment was evaluated using the notched Izod impact test at -37°C. Figure 19 and Table 8). If blended at 185°C, the poorly dispersed systems show little improvement in impact strength even with the addition of SEBS rubber. However, if blended at 230°C, their impact strength improves significantly with the addition of SEBS rubber. Adding more SEBS rubber to these well-dispersed systems can achieve even higher toughness. The 8phr / 230°C system shows 10.33 kJ / m 2 The impact strength is almost 4 times that of the 0phr / 230℃ non-compatibilized system.

[0163] Fracture mechanism research

[0164] To help understand the toughening mechanism, a DN-4PB Charpy impact test was conducted. Two nearly identical pre-cracks should have the same probability of growth when the specimen is impacted. One of these pre-cracks will eventually fail and fracture, while the other will survive and only grow subcritically. Because the surviving pre-crack also experiences crack growth ahead of its crack tip, observing the damaged zone ahead of the crack tip provides valuable information for understanding the toughening mechanism of these systems. Figures 20A-20D The damaged zone ahead of the crack tip in the 8phr / 185°C and 8phr / 230°C systems, observed under brightfield and crossed polarizers, is shown. In the 8phr / 185°C system, the crack propagates in a brittle manner, penetrating directly through large BPS particles. These large BPS aggregates act as defects through which the crack can easily rupture, resulting in minimal energy absorption. However, for the well-dispersed 8phr / 230°C system, large-scale cracks are observed under brightfield optical microscopy. These high-intensity cracks facilitate energy absorption, resulting in the significantly higher impact strength of the 8phr / 230°C system. Furthermore, under crossed polarizers, birefringence is observed in the damaged zone of the 8phr / 230°C system, while no birefringence is observed in the damaged zone of the 8phr / 185°C system. This indicates the occurrence of shear bands during crack propagation, likely due to cavitation in the core-shell rubber.

[0165] In addition to observing the damaged zone ahead of the crack tip, fracture surface analysis can also provide useful information about the toughening mechanism. Figures 21A-21D Figure 2 shows the fracture surfaces of the 8phr / 185°C and 8phr / 230°C systems observed under SEM. Large BPS particles fractured brittlely in the 8phr / 185°C system, consistent with the observations in Figure 21B. BPS particles were also observed to be exfoliated from the LLDPE matrix, indicating poor adhesion between the BPS and LLDPE phases in the poorly dispersed 8phr / 185°C system. Furthermore, numerous small spherical particles were distributed within the LLDPE matrix and exfoliated from the LLDPE phase. These spherical particles are likely SEBS rubber, dispersed within the LLDPE phase rather than encapsulated around the BPS particles due to inadequate melt mixing at 185°C. However, in the well-dispersed 8phr / 230°C system, the small BPS particles encapsulated by the SEBS rubber were uniformly distributed. More importantly, these particles were firmly embedded in the LLDPE matrix, demonstrating strong interfacial adhesion with the LLDPE, consistent with previous rheological findings.

[0166] This study investigated the morphological, interfacial, and mechanical properties of LLDPE / BPS blends compatibilized and toughened with SEBS rubber. When melt-mixed at a suitable processing temperature (230°C), the Izod impact strength of the LLDPE / BPS / SEBS blend (75 / 25 / 8 weight ratio) at -37°C was nearly tripled compared to the uncompatibilized system. The low-cost and simple process presented here has the potential to expand the range of LLDPE applications to those requiring flame retardancy and low-temperature impact resistance.

[0167] in conclusion

[0168] The goal of this study was to compatibilize and improve the properties of LLDPE / BPS polymer blends. Not only did the addition of SEBS rubber as a compatibilizer, but also the processing temperature significantly influence the morphology and properties. Melt mixing at 230°C brought the viscosity ratio closer to 1, and the addition of SEBS rubber further reduced the BPS particle size to less than 0.5 μm, resulting in a core-shell structure. This refined morphology and strong interfacial interactions, characterized by rheological properties, together contributed to a threefold increase in Izod impact strength at -37°C. DN-4PB studies revealed that cracking and shear banding caused by cavitation in the core-shell rubber were the two primary toughening mechanisms for the well-dispersed system. The ease of processing makes this work valuable for the development of flame-retardant LLDPE. Future work will investigate the effects of varying morphology or BPS particle size on the flame retardancy of these systems.

[0169] Example 5: Additional compositions using commercially available polymers

[0170] Material

[0171] The flame retardant plastic compositions according to the present disclosure were produced using the following commercial polymers:

[0172]

[0173]

[0174] Experimental procedures

[0175] The examples from composition 1 to composition 9 (see Table 10) were extruded in a ThermoFisher Process 11 twin-screw extruder. The extrusion temperatures in Table 10 indicate that all barrel temperatures were 190°C or 230°C, depending on each composition. The twin-screw speed of the extruder and the single-screw speed of the feeder were 60 RPM and 5 RPM, respectively. After extrusion, the strands were cooled in a water bath and manually chopped. Before being fed to the extruder, homopolymer PP pellets and BPS1 particles (or BPS2 powder) with or without thermoplastic elastomer pellets (or powder) were all manually blended in a transparent plastic bag. The total feed amount was 2 kg, and the amount finally collected after extrusion was 1.5 kg.

[0176]

[0177]

[0178]

[0179]

[0180]

[0181]

[0182]

[0183]

[0184]

[0185]

[0186]

[0187]

[0188]

[0189]

[0190] The compositions in Tables 11 to 13 were compounded in a Haake Rheocord (Model 40) mixer for 7 minutes to obtain formulations containing EPB or BPS1 or ethylene-bis-tetrabromophthalimide. The total volume of one compounding batch was about 50 mL.

[0191] The order in which each ingredient is fed into the mixing chamber is resin, followed by brominated flame retardant, followed by rubber, and then compatibilizer. For example, in Actual Example 1, after homo-PP is completely melted, EBP is added for 1 minute, followed by hydrogenated rubber for 30 seconds, and then SEBS-g-MAH rubber for 30 seconds. The total compounding time is 7 minutes.

[0192] After 7 minutes, the chamber was opened, and the samples were collected and then cut into dimensions of 5 mm × 5 mm × 2 mm.

[0193] Injection molding was performed at a barrel temperature of 190° C. and a mold temperature of 60° C. The cooling time was 10 seconds and the injection pressure was 670 bar. The molded bars had dimensions of 90×12.7×3.2 mm.

[0194] After the bars were machined into dimensions of 63.5×12.7×3.2 mm with a 45° notch of 2.54 mm depth at the center, Izod impact and plane strain critical stress intensity factor K1c were tested at 25°C or -37°C based on ASTM D256 and ASTM D5056.

[0195] The examples of compositions 25 to 53 in Tables 14 to 18 were prepared by first compounding the raw materials in a Werner & Pfleider (Coperion) ZSK-30 twin-screw extruder (L / D 24, screw diameter 30 mm, barrel temperature 165°C-200°C from hopper to die) with two feeders. Direct compounding means that all materials are fed at once. Pellets and granules are fed through one feeder, and premixed powder is fed through another feeder. The extrudate strands are cooled in an ice-water bath, air-dried, and pelletized. Continuous compounding means that the BPS and elastomeric polymer are first extruded with or without filler. The first compounded material is fed to the second extruder as a masterbatch with the base resin. The pellets are then injection molded into test bars on a Boy 30A (35 ton) machine at a barrel temperature of 200°C, an injection pressure of 10 MPa, and a mold temperature of 35°C with a cooling time of 15 seconds.

[0196] The examples from composition 54 to composition 57 (Table 19) were extruded in a ThermoFisher Process 11 twin-screw extruder with one feeder. The barrel temperature of the extruder was 285°C to 320°C from the hopper to the die. The twin-screw speed was 150 RPM and the feed rate was 0.2 kg / h. The extruded strands were cooled in a conveyor belt and then chopped by a pelletizer. Before feeding into the extruder, the PPA pellets and BPS1 pellets with or without thermoplastic elastomer pellets (or powder) were all manually blended in a transparent plastic bag. The chopped pellets after extrusion were injection molded into izod rods via a ThermoFisher Minijet pro at an injection pressure of 3,450 psi, a barrel temperature of 345°C, a mold temperature of 90°C, and a cooling time of 15 seconds. For continuous compounding, the blended material was prepared in the same manner as in claim 126.

[0197] TEM observation

[0198] Blocks having a size of 3 x 3 x 10 mm were cryo-ultramicrotomed by a diamond knife at a temperature of -120°C to obtain TEM thin sections (100 to 120 nm thickness) on TEM copper grids (400 mesh size).

[0199] Each thin section on a TEM copper grid was vapor stained with 0.5% ruthenium tetroxide aqueous solution at ambient temperature for 10 minutes to obtain contrast differences between the resin, rubber, and brominated FR.

[0200] The morphologies were observed under a JEOL 1200EX or JEOL JEM-1400 at an electron beam voltage of 100 keV or 120 keV, respectively.

[0201] Figures 22A-22Q TEM images of the compositions from Tables 10-13 are shown below: Figure 22A Display composition 1, Figure 22B Display composition 3, Figure 22C Display composition 4, Figure 22D Display composition 5, Figure 22E Display composition 7, Figure 22F Display composition 8, Figure 22G Display composition 10, Figure 22H Display composition 11, Figure 22I Display composition 12, Figure 22J Display composition 16, Figure 22K Display composition 17, Figure 22L Display composition 18, Figure 22M Display composition 20, Figure 22N Display composition 21, Figure 22O Display composition 22, Figure 22P Display composition 23, Figure 22Q Display composition 24, Figure 22R Display composition 25, Figure 22S Display composition 26, Figure 22T Display composition 31, Figure 22U Display composition 34, Figure 22V Display composition 48, Figure 22X Display composition 52, Figure 22Y Display composition 54, and Figure 22Z Display composition 56.

[0202] It should be emphasized that the above-described embodiments of the present disclosure are merely possible examples of implementation forms set forth for a clear understanding of the principles of the present disclosure. Many variations and modifications may be made to the above-described embodiments without departing substantially from the spirit and principles of the present disclosure. All such modifications and variations are intended to be included within the scope of the present disclosure and are protected by the following claims.

[0203] References

[0204] 1. Abis, L.; et al, 2000, Macromol Chem Physic, 201: 1732-1741.

[0205] 2. Agari, Y.; et al, 1992, J Appl Polym Sci 1992, 45: 1957-1965.

[0206] 3. Ageyeva, T. et al, 2019, Composites, in: J. Karger-Kocsis et al (Eds.), Polypropylene Handbook: Morphology, Blends and Composites, Springer International Publishing, pp. 481-578.

[0207] 4. Ahmed, L. et al., 2017, Journal of Loss Prevention in the Process Industries 49: 228-239.

[0208] 5.Aroguz,A.et al.,2005,Chapter 26-Thermal characterization andmorphological studies of binary and ternary polymeric blends ofpolycarbonate,brominated polystyrene,and poly(2,6-dimethyl-1,4-phenyleneoxide),ACS Symposium Series,916:351-368.

[0209] 6.Aroguz,A.et al.,2006,European polymer journal 42:311-315.

[0210] 7. A.Z.et al.,2000,Journal of applied polymer science 75:225-231.

[0211] 8.Bains,M.;et al,1994,Polymer Engineering&Science,34:1260-1268.

[0212] 9.Baker,W.E.;et al,1987,Polym Eng Sci,27:1634-1641.

[0213] 10.Bakker,A.,1990,Fatigue&Fracture of Engineering Materials&Structures 13:145-154.

[0214] 11.Bucknall,C.B.,1977,Impact Strength,in:C.B.Bucknall(Ed.)ToughenedPlastics,Springer Netherlands,Dordrecht,pp.272-304.

[0215] 12.Camino,G.et al.,1991,Polymer Degradation and Stability 33:131-154.

[0216] 13.Campo,E.A.,2008,3-ThermalProperties of Polymeric Materials,in:E.A.Campo(Ed.)Selection of Polymeric Materials,William Andrew Publishing,Norwich,NY,pp.103-140.

[0217] 14.Chen,M.et al.,2014,High Performance Polymers,26:445-454.

[0218] 15.Chen,Q.;et al,2021,Compos SciTechnol,207:108739.

[0219] 16.De Schryver,D.et al,1999,Polymer Degradation and Stability 64:471-477.

[0220] 17.Diaz,M.F.et al,2002,Polymer,43:4851-4858.

[0221] 18.Dobrovszky,K.et al,2016,Polym Bull,73:2719-2739.

[0222] 19.Doucet,D.K.et al.,US 5,281,648,1994.

[0223] 20.Ezati,P.et al,2008,Iranian Polymer Journal,669-679.

[0224] 21.Favis,B.D.,et al.,1987,Polymer Engineering&Science,27:1591-1600.

[0225] 22.Gahleitner,M.et al.,2019,Polypropylene Copolymers,in:J.Karger-Kocsis et al(Eds.),Polypropylene Handbook:Morphology,Blends and Composites,SpringerInternational Publishing,pp.295-355.

[0226] 23.Georlette,P.,2001,Plastics,Additives and Compounding 3:28-33.

[0227] 24.Green,J.,1982,The Flame Retardation of Polyolefins,in:M.Lewin etal(Eds.),Flame-Retardant Polymeric Materials:Volume 3,Springer New York,Boston,MA,pp.1-37.

[0228] 25.Guinea,G.et al.,1998,InternationalJournalof Fracture 89:103-116.

[0229] 26.Han,C.D.;et al,1996,Polymer Engineering&Science,36:1360-1376.

[0230] 27.Ho,R.et al.,2012,Pharmaceutical research 29:2806-2816.

[0231] 28.Hobbs,S.et al,1988,Polymer 29:1598-1602.

[0232] 29.Horiuchi,S.;et al,1997,Polymer,38:59-78.

[0233] 30.Jafari,S.;et al,2000,Polymer,46:5082-5093.

[0234] 31.Janssen,J.;et al,1993,J Rheol,37:597-608.

[0235] 32.Jiang,Z.Y.;et al.,2020,J Appl Polym Sci,137:48966.

[0236] 33.Jiang,Z.;et al,2019,Polymer,160:231-237.

[0237] 34.Jiang,Z.;et al,2021,Polym Int,70:1090-1098.

[0238] 35.Kotian,V.M.et al.,US 9,018,298,2015.

[0239] 36.Lai,X.et al.,2012,J.Macromolecular Sci.,Part B:Physics,51:35-47.

[0240] 37.Landry,S.D.et al.,US 5,387,636,1995.

[0241] 38.Lauke,B.et al,2002,Composites science and technology 62:1965-1978.

[0242] 39.Lee,J.K.;et al,1999,Polymer,40:6277-6296.

[0243] 40.Lee,J.K.;et al,2000,Polymer,41:1799-1815.

[0244] 41.Li,H.et al.,2017,Polymer 108:1-10.

[0245] 42.Li,Y.et al.,2002,Journalof materials science 37:2447-2459.

[0246] 43.Liu,H.;et al,2012,Polymer,53:272-276.

[0247] 44.Luzinov,I.;et al,2000,Polymer,41:3381-3389.

[0248] 45.Matonis,V.A.,et al.,1969,Polymer Engineering&Science 9:90-99.

[0249] 46.Noh,K.et al.,2021,Polymer 223:123709.

[0250] 47.Ran,S.Y.et al,2014,Polym Int,63:1835-1841.

[0251] 48.Ravati,S.et al,2010,B.D.Favis,Polymer 51:4547-4561.

[0252] 49. J.,1995,Polymer Engineering&Science,35:1917-1922.

[0253] 50.Rudin,A.,1980,Journal of Macromolecular Science-Reviews inMacromolecular Chemistry,19:267-292.

[0254] 51.Shahbazi,K.et al,2012,Polym Bull,69:241-259.

[0255] 52.So,P.et al.,1976,Polymer Engineering&Science 16:785-791.

[0256] 53.Tai,C.M.et al.,2001,Journalof Applied Polymer Science 80:2718-2728.

[0257] 54.Thaweephan,P.et al.,2001,Journal of Polymer Science Part B:PolymerPhysics 39:1605-1615.

[0258] 55.Ticehurst,M.D.,et al.,1994,InternationalJournalof Pharmaceutics111:241-249.

[0259] 56.Tsui,C.P.et al,2001,Journalof Materials Processing Technology 117:105-110.

[0260] 57.Valera,T.S.,et al.,2006,Macromolecules 39:2663-2675.

[0261] 58.Van Krevelen,D.W.et al.,2009,Chapter 8-InterfacialEnergyProperties,in:D.W.Van Krevelen et al(Eds.),Properties of Polymers(FourthEdition),Elsevier,Amsterdam,pp.229-244.

[0262] 59.Vital,A.,et al.,2015,Polymer 76:123-130.

[0263] 60.Wei,G.-X.et al,2000,Polymer 41:2947-2960.

[0264] 61.Wei,G.-X.et al.,2000,Journalof Materials Science 35:555-566.

[0265] 62.Wei,G.-X.et al.,2000,Polymer Engineering&Science 40:1979-1988.

[0266] 63.Weil,E.D.et al,2008,Journal of Fire Sciences 26:5-43.

[0267] 64.Williams,A.et al.,2022,Applied Surface Science 579:152185.

[0268] 65.Wu,S.,1987,Polymer Engineering&Science,27:335-343.

[0269] 66.Xu,J.et al.,2022,Polymers and Polymer Composites 30:09673911221083769.

[0270] 67.Yee,A.F.et al.,2002,Impact Resistance,Encyclopedia of PolymerScience and Technology,(Ed.),John Wiley and Sons,Inc..

[0271] 68.Zhao,Y.Q.;et al,2014,J Appl Polym Sci,131:40146.

[0272] 69.Zhu,Z.;et al,2022.Nano Materials Science,4:251-258.

Claims

1. A flame retardant plastic composition comprising a polymer component and a brominated flame retardant, wherein the brominated flame retardant comprises one or more particles at least partially encapsulated by a thermoplastic toughening agent.

2. The flame retardant plastic composition of claim 1 , wherein the polymer component comprises polystyrene, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (VLDPE), ultra low density polyethylene (ULDPE), medium density polyethylene (MDPE), polypropylene (PP), polymethylpentene (PMP), polybutene-1 (PB-1), ethylene-octene copolymer, stereoblock PP, olefin block copolymer, propylene-butane copolymer, polyisobutylene (PIB), poly(α-olefin), ethylene propylene rubber (EPR), ethylene propylene diene monomer rubber (EPDM rubber), high density polyethylene (HDPE), ultra high density polyethylene (UHDPE), polyamide, polyester, styrenic polymer or copolymer, crosslinkable or crosslinked polyethylene (PEX or XLPE), or any combination thereof.

3. The flame retardant plastic composition of claim 2, wherein the polyamide comprises nylon 6,6; nylon 6; nylon 6,10; nylon 11; nylon 6,12; nylon 12; nylon 6,9; nylon 4,6; poly(m-phenylene isophthalamide); poly(p-phenylene terephthalamide); co-poly(p-phenylene terephthalamide / d,4′-diphenyl ether terephthalamide); PA66 / 6, PA6T, PA9T, PA10T, PA4T, poly(m-phenylene sebacate), poly(m-phenylene adipamide), copolymers thereof, or any combination thereof.

4. The flame retardant composition of claim 2, wherein the polyester comprises polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT), poly(cyclohexylene dimethylene terephthalate) (PCT), polylactic acid (PLA), polycaprolactone (PCL), polyethylene terephthalate glycol (PETG), polycyclohexylene dimethylene terephthalate (PCTG), or any combination thereof.

5. The flame retardant composition of claim 2, wherein the styrenic polymer or copolymer comprises poly(styrene-co-acrylonitrile) (SAN), poly(acrylonitrile-co-butadiene-styrene) (ABS), or any combination thereof.

6. The flame retardant plastic composition according to claim 1 or 2, wherein the polymer component is selected from polypropylene, polystyrene, linear low density polyethylene (LLDPE) or ethylene-1-octene copolymer.

7. The flame retardant plastic composition of any one of claims 1 to 6, wherein the brominated flame retardant comprises 1,2-bis(pentabromophenyl)ethane, brominated polystyrene, ethylene-bis-tetrabromophthalimide, decabromodiphenyl ether, brominated polystyrene: poly(bromostyrene), polyvinyl bromide, polyvinylidene bromide, poly(2-bromoethyl methacrylate), poly(2,3-dibromopropyl methacrylate), poly(methyl-a-bromoacrylate), brominated butadiene styrene copolymer, or any combination thereof.

8. The flame retardant plastic composition of any one of claims 1 to 7, wherein the thermoplastic toughening agent comprises a thermoplastic elastomer.

9. The flame retardant plastic composition of any one of claims 1 to 8, wherein the thermoplastic toughening agent comprises a styrenic block copolymer, a thermoplastic polyurethane, a nitrile rubber, an acrylic elastomer, a copolyester elastomer, a thermoplastic polyetherester elastomer (TPEE), a thermoplastic amide ether elastomer (TAEE), a chlorinated rubber, an ionomer, a thermoplastic vulcanizate, or any combination thereof.

10. The flame retardant plastic composition of claim 9, wherein the nitrile rubber comprises hydrogenated nitrile rubber.

11. The flame retardant plastic composition of claim 9, wherein the styrenic block copolymer comprises styrene-ethylene butylene-styrene block copolymer (SEBS), maleic anhydride grafted SEBS block copolymer, styrene-ethylene propylene-styrene block copolymer (SEPS), or any combination thereof.

12. The flame retardant plastic composition of claim 11, wherein the SEBS block copolymer has a styrene to ethylene and butylene ratio of about 10:90 to about 70:

30.

13. The flame retardant plastic composition of claim 9, wherein the thermoplastic polyurethane comprises polyester polyurethane, polyether polyurethane or any combination thereof.

14. The flame retardant plastic composition of claim 9, wherein the acrylic elastomer comprises an ethylene acrylic acid terpolymer.

15. The flame retardant plastic composition of claim 9, wherein the chlorinated rubber comprises polychloroprene, chlorinated polyethylene copolymer, or any combination thereof.

16. The flame retardant plastic composition according to any one of claims 1 to 15, further comprising Sb2O3.

17. The flame retardant plastic composition of claim 16, wherein the flame retardant plastic composition comprises about 1 wt% to about 10 wt% Sb2O3.

18. The flame retardant plastic composition according to any one of claims 1 to 17, further comprising a compatibilizer.

19. The flame retardant plastic composition of claim 18, wherein the compatibilizer comprises maleic anhydride grafted polypropylene.

20. The flame retardant plastic composition of any one of claims 1 to 19, wherein the flame retardant plastic composition comprises from about 65 wt% to about 85 wt% of the polymer component, from about 5 wt% to about 35 wt% of the brominated flame retardant, from about 4 wt% to about 8 wt% of the thermoplastic toughening agent, and from about 0 wt% to about 2 wt% of the compatibilizer, based on the total weight of the polymer component, the brominated flame retardant, the thermoplastic toughening agent, and the compatibilizer, if present.

21. The flame retardant plastic composition according to any one of claims 1 to 20, further comprising a filler.

22. The flame retardant plastic composition of claim 21, wherein the filler comprises talc, calcium carbonate, AgO, ZnO, CaO, MnO, Al(OH)3, AlO(OH), Mg(OH)2, kaolinite, wollastonite, mica, glass beads, or any combination thereof.

23. The flame retardant plastic composition of any one of claims 1 to 22, wherein the one or more particles of the brominated flame retardant comprise (i) a plurality of particles that are individually partially encapsulated by the thermoplastic toughening agent, (ii) a plurality of particles that are individually completely encapsulated by the thermoplastic toughening agent, (iii) a plurality of clusters of two or more particles, wherein a single cluster in the plurality of clusters as a whole is partially encapsulated by the thermoplastic toughening agent, (iv) a plurality of clusters of two or more particles, wherein a single cluster in the plurality of clusters as a whole is completely encapsulated by the thermoplastic toughening agent, or (v) any combination thereof.

24. The flame retardant plastic composition of any one of claims 1 to 23, wherein the one or more particles at least partially encapsulated by the thermoplastic toughening agent have a core-shell structure.

25. The flame retardant plastic composition according to any one of claims 24, wherein the shell layer of the core-shell structure has an average thickness of about 5 nm to about 10 μm.

26. The flame retardant plastic composition of claim 25, wherein the ratio of the average thickness of the shell layer to the average length in at least one dimension of the core layer of the core-shell structure is from about 0.05:1 to about 1:1, most typically in the range of 0.05:1 to 0.25:

1.

27. The flame retardant plastic composition of any one of claims 1-26, wherein the flame retardant plastic composition has a melt flow rate of about 7.5 to about 20 g / 10 min.

28. An article comprising the flame retardant plastic composition of any one of claims 1 to 27.

29. The article of any one of claims 28, wherein the article comprises an electronic component, an automotive component, insulation, carpet, wall covering, covering for cables or wires, textiles, adhesives, or any combination thereof.

30. A method for preparing the flame retardant plastic composition according to any one of claims 1 to 29, the method comprising: (a) blending a polymer component, a brominated flame retardant, and a thermoplastic toughening agent to form a precursor mixture; as well as (b) extruding the precursor mixture at elevated temperature.

31. The method of claim 30, wherein step (a), step (b), or both steps (a) and (b) are performed in a twin-screw extruder.

32. The method of claim 30 or 31 , wherein the elevated temperature is from about 160°C to about 230°C.

33. The method of claim 31 or 32, wherein the twin-screw extruder has a speed of about 60 rpm.

34. The method of any one of claims 30-33, further comprising adding Sb2O3 during step (a) or step (b).

35. A method of preparing the flame retardant plastic composition of any one of claims 1 to 29, the method comprising blending the polymer components, the brominated flame retardant, the thermoplastic toughening agent and optionally Sb2O3 in a double-arm mixer.

36. A method for preparing the flame retardant plastic composition according to any one of claims 1 to 29, the method comprising: (a) blending a polymer component and a brominated flame retardant to produce a masterbatch; (b) blending the masterbatch and the thermoplastic toughening agent to form a second mixture; as well as (c) extruding the second mixture at an elevated temperature.

37. The method of claim 36, wherein one or more of steps (a), (b), and (c) are performed in a twin-screw extruder.

38. The method of claim 36 or 37, wherein the elevated temperature is from about 160°C to about 230°C.

39. The method of any one of claims 36-38, wherein the twin-screw extruder has a speed of about 60 rpm.

40. The method of any one of claims 36-39, further comprising adding Sb2O3 during step (a) or step (b).

Images