Patent Publication Number: US-2017369673-A1

Title: Flame retardant polybutylene succinate compound

Description:
CLAIM OF PRIORITY 
     This application claims priority from U.S. Provisional Patent Application Ser. No. 62/096,012 bearing Attorney Docket Number 12014030 and filed on Dec. 24, 2014, which is incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention concerns a highly flame retardant polybutylene succinate (PBS) compound using non-halogenated ingredients for use in applications having stringent requirements for flammability, heat release, smoke and toxicity. 
     BACKGROUND OF THE INVENTION 
     Thermoplastic compounds, unlike wood, metal, or glass, do not rot, rust, or shatter. For that reason, the world in the past seventy years has seen a revolution in material science arising from the combination of a thermoplastic resin and one or more functional additives to provide specific properties to the resin. 
     Unlike wood but like metal and glass, at a given temperature, a thermoplastic resin can melt. Its processing versatility benefits from its capacity to mix with the functional additives while in a molten state. 
     But in use, the exposure of a fully formed thermoplastic article to excessive heat or flame can be quite detrimental to property and person. Flame retardancy is a key attribute for many household items, for example hair dryers, curtains and drapes, water heaters and kitchen appliances. In addition, materials that are non-flammable and non-combustible are critical for many applications in industries, such as electronics, telecommunications, and transportation. Therefore, flame retardants, drip suppressants, mineral fillers, and char formers are frequently added as functional additives to help thermoplastic compounds retard the effects of heat or flame from melting or even burning. 
     Recently non-halogenated flame retardants have become popular because they minimize the release of halogenated chemicals if the plastic article would begin to degrade, melt, or burn. Polymers having non-halogenated flame retardants are particularly useful for enclosed areas, such as aircraft cabins, submarines, ships, subways and high rise buildings. However, polymer blends using non-halogenated flame retardants are often more difficult to process and have reduced physical and mechanical properties when compared to the original thermoplastic resin. 
     Currently very few polymer materials are available that can meet the high flammability standards required for use in aircraft interiors. Passing Level 4 Performance Criteria of FAR 25.853, which includes flammability, heat release rate, smoke and toxicity requirements, is particularly difficult. 
     SUMMARY OF THE INVENTION 
     What the art needs is a non-halogenated polymer capable of meeting the more stringent standards for flammability, heat release rate, smoke and toxicity required for enclosed spaces. 
     The present invention has found a highly flame retardant polybutylene succinate (PBS) compound using a non-halogenated intumescent flame retardant system. One aspect of the invention is a flame retardant PBS compound having PBS, ammonium polyphosphate, a melamine compound as a synergist, a mineral filler, and optionally polytetrafluoroethylene (PTFE). The mineral filler can be quaternary ammonium salt modified montmorillonite, talc or a combination thereof. An inorganic heat stabilizer, such as Irganox™ B 225, optionally can be added for processing. In addition, an impact modifier optionally can be added for impact strength. 
     Another aspect of the invention is a flame retardant PBS compound used to make polymeric articles. Another aspect of the invention is a flame retardant PBS compound used to make polymeric articles via additive manufacturing for 3D printing. Rheology modifiers can be used to control the viscosity for the different processing conditions. 
     Features of the invention will be explored below. 
     EMBODIMENTS OF THE INVENTION 
     Polybutylene Succinate 
     Polybutylene succinate (PBS) is a biodegradable aliphatic polyester that consists of polymerized units of butylene succinate, with repeating C 8 H 12 O 4  units shown below: 
     
       
         
         
             
             
         
       
     
     PBS has the CAS # of 67423-06-7. PBS is commercially available from several chemical manufacturers, including Samsung Fine Chemicals, Co. Ltd., Showa Denko K.K. and Mitsubishi Chemical. 
     Ammonium Polyphosphate 
     Ammonium polyphosphates are inorganic salts that are produced from the reaction of polyphosphoric acid and ammonia and has the chemical formula [NH 4 PO 3 ] n . Ammonium polyphosphates can be used as an intumescent flame retardant (FR) system. When exposed to heat or fire, ammonium polyphosphate will begin to decompose back to ammonia and phosphoric acid. The phosphoric acid acts as a catalyst in the dehydration of carbon-based poly-alcohols. The phosphoric acid reacts with such alcohol groups to form phosphate esters, which further decompose to release carbon dioxide. The release of non-flammable carbon dioxide, as well as nitrogen further degraded from ammonia and water, reduces the amount of available oxygen to the material that is burning. In contrast, halogen-based systems would result in the release of gases that contained halogens into the environment. 
     Ammonium polyphosphates are commercially available from several manufactures, including JLS Chemicals which offers JLS PNP1C, JLS PNP2V, and JLS PNP3D. Other commercial products are Clariant Exolit® AP, Amfine™ FP, Budenheim Budit™, Chitec Zuran®, and JJI JJAZZ™. 
     For the present invention, the flame retardant system can contain more than one type of ammonium polyphosphate. 
     Melamine Cyanurate 
     Melamine cyanurate, also known as melamine-cyanuric acid adduct or melamine-cyanuric acid complex, serves as a synergist for the ammonium polyphosphate. Melamine cyanurate is a crystalline complex formed from a 1:1 mixture of melamine and cyanuric acid and has a CAS No. of 37640-57-6 and a IUPAC name of 1,3,5-Triazine-2,4,6(1H,3H,5H)-trione, compd. with 1,3,5-triazine-2,4,6-triamine (1:1). 
     Quaternary Ammonium Salt Modified Montmorillonite 
     A mineral filler, quaternary ammonium salt modified montmorillonite is an organically modified nanoclay. Nanoclays are nanoparticles of layered mineral silicates are used to increase the strength, mechanical modulus and toughness of the polymer while improving barrier and flame retardant properties. Preferred for the present invention are nanoclays wherein 90% of the particles are less than 13 μm, and d spacing of about 18.5 Å. 
     Talc 
     Talc is used often in thermoplastic compounds as a mineral filler. Talc is a naturally occurring mineral, identified generally as a hydrous magnesium silicate having a Chemical Abstract Services Number of CAS #14807-96-6. Its formula is 3MgO.4SiO 2 .H 2 O. 
     In flame retardant thermoplastic compounds, talc can also assist in flame retardance by being a barrier to oxygen and increasing viscosity of the molten polymer matrix during combustion. 
     Talc is available from a number of commercial sources. Non-limiting examples of such talc useful in this invention are Jetfine®, Jetfil® brand talcs from Imerys Talc; Flextalc™ brand talcs from Specialty Minerals; and Talcron™ brand talcs from Mineral Technologies, Inc. Preferred for the present invention are ultra-fine, micronized talcs such as Jetfine® 3 CA, in which 50% of the particles are less than 1000 nm. 
     Optional Polytetrafluoroethylene 
     Polytetrafluoroethylene (PTFE) is known to be useful as a drip suppressant because it tends to shrink upon exposure to heat from a flame and hence retard dripping. PTFE can have a particle size ranging from about 5 μm to about 25 μm with the possibility of aggregation and agglomeration. 
     PTFE is commercially available from a number of manufacturers, but the best known is the Teflon™ brand from DuPont which invented the polymer. 
     Though PTFE is fluorinated, its presence in the compound is not regarded by those having skill in the art of flame retardant compounds as compromising the non-halogenated characteristics of the flame retardant itself because the amount of PTFE present is very minor. Therefore, the use of a fluorinated drip suppressant in the amounts identified in this invention does not disqualify the compound from being considered a non-halogenated flame retarded thermoplastic compound according to the course of conduct in the thermoplastic compound industry. 
     Additional Additives 
     A variety of additives known to those skilled in the art can be included in the flame retardant PBS compounds of the present invention to improve processing or performance properties. 
     The compound of the present invention can include conventional plastics additives in an amount that is sufficient to obtain a desired processing or performance property for the compound. The amount should not be wasteful of the additive nor detrimental to the processing or performance of the compound. Those skilled in the art of thermoplastics compounding, without undue experimentation but with reference to such treatises as  Plastics Additives Database  (2004) from Plastics Design Library (elsevier.com website), can select from many different types of additives for inclusion into the compounds of the present invention. 
     Non-limiting examples of optional additives include adhesion promoters; biocides; anti-fogging agents; anti-static agents; anti-oxidants; bonding, blowing and foaming agents; dispersants; fillers and extenders; smoke suppressants; impact modifiers; initiators; lubricants; micas; pigments, colorants and dyes; plasticizers; processing aids; release agents; silanes, titanates and zirconates; slip agents, anti-blocking agents; stabilizers; stearates; ultraviolet light absorbers; viscosity regulators; waxes; catalyst deactivators, and combinations of them. 
     Optionally, epoxy-functional styrene-acrylic oligomers also can be added. These oligomers are functional additives having a variety of applications in polymer compositions, including improving chain extension, compatibilization, hydrolytic stabilization, and increased dispersion. A commercially available example of epoxy-functional styrene-acrylic oligomer is the Joncryl® product line manufactured by BASF. 
     Range of Ingredients 
     Table 1 shows acceptable, desirable and preferable ranges of ingredients useful in the present invention, all expressed in weight percent (wt. %) of the entire compound. The compound can comprise, consist essentially of, or consist of these ingredients. Any number between the ends of the ranges is also contemplated as an end of a range, such that all possible combinations are contemplated within the possibilities of Table 1 as candidate compounds for use in this invention. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 Ingredient (Wt. %) 
                 Acceptable 
                 Desirable 
                 Preferable 
               
               
                   
               
             
            
               
                 Polybutylene succinate 
                 45-70 
                 59-70 
                 50-52 
               
               
                 Ammonium polyphosphate 
                 15-30 
                 24-30 
                 30 
               
               
                 Quaternary ammonium salt 
                 0-5 
                 0-5 
                 0-3 
               
               
                 modified montmorillonite 
               
               
                 Melamine cyanurate 
                 0-5 
                 4-5 
                  5 
               
               
                 Optionally 
                 0-1 
                     0-0.1 
                     0-0.1 
               
               
                 polytetrafluoroethylene 
               
               
                 Talc 
                 0-5 
                 0-5 
                 0-5 
               
               
                 Optional additives 
                  0-15 
                  0-10 
                 0-7 
               
               
                   
               
            
           
         
       
     
     Processing 
     The preparation of compounds of the present invention is uncomplicated. The compound of the present can be made in batch or continuous operations. 
     Mixing in a continuous process typically occurs in a single or twin screw extruder that is elevated to a temperature that is sufficient to melt the polymer matrix with addition of other ingredients either at the head of the extruder or downstream in the extruder. Extruder speeds can range from about 50 to about 500 revolutions per minute (rpm), and preferably from about 350 to about 450 rpm. Typically, the output from the extruder is pelletized for later extrusion or molding into polymeric articles. 
     Mixing in a batch process typically occurs in a Banbury mixer that is capable of operating at a temperature that is sufficient to melt the polymer matrix to permit addition of the solid ingredient additives. The mixing speeds range from 60 to 1000 rpm. Also, the output from the mixer is chopped into smaller sizes for later extrusion or molding into polymeric articles. 
     Subsequent extrusion or molding techniques are well known to those skilled in the art of thermoplastics polymer engineering. Without undue experimentation but with such references as “Extrusion, The Definitive Processing Guide and Handbook”; “Handbook of Molded Part Shrinkage and Warpage”; “Specialized Molding Techniques”; “Rotational Molding Technology”; and “Handbook of Mold, Tool and Die Repair Welding”, all published by Plastics Design Library (elsevier.com website), one can make articles of any conceivable shape and appearance using compounds of the present invention. 
     Usefulness of the Invention 
     The flame retardant compounds of the present invention can be shaped by extrusion, molding, calendering, thermoforming, additive manufacturing for 3-D printing, or other means of shaping into any plastic article usable in an interior or confined space where fire can cause personal injury or property damage. The compounds resist melting and dripping. 
     Literally any plastic article useful in a human-occupied space such as a building, a vehicle, or a tunnel can benefit from the flame retardancy of this polyurethane compound. 
     Flame retardant polymer articles are sold into the following markets: appliance, building and construction, consumer, electrical and electronic, healthcare, industrial, packaging, textiles, transportation, and wire and cable. Compounds of this invention can be used in any of those markets, but especially into the transportation market for aircraft interiors. 
     Examples provide data for evaluation of the unpredictability of this invention. 
    
    
     EXAMPLES 
     Table 2 shows the list of ingredients. Table 3 shows the extrusion conditions. Table 4 shows the molding conditions. Table 5 shows the recipes and Tables 6A and 6B the test results. Properties of a typical flame retardant polymer compound of the invention are shown in Table 7. 
     
       
         
           
               
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 Brand 
                 Chemical 
                 Purpose 
                 Maker 
               
               
                   
               
             
            
               
                 PBS ENP01 
                 Polybutylene succinate 
                 Polymer 
                 Samsung Fine 
               
               
                 G4560m 
                 (CAS # 67423-06-7) 
                 matrix 
                 Chemicals Co., Ltd. 
               
               
                 PBS ENP01 
                 Polybutylene succinate 
                 Polymer 
                 Samsung Fine 
               
               
                 G4560J 
                 (CAS # 67423-06-7) 
                 matrix 
                 Chemicals Co., Ltd. 
               
               
                 JLS-APP 
                 Ammonium 
                 Flame 
                 Hangzhou JLS 
               
               
                   
                 polyphosphate 
                 retardant 
                 Flame Retardants 
               
               
                   
                   
                   
                 Chemical Co., Ltd 
               
               
                 FP2200 
                 Ammonium 
                 Flame 
                 Adeka 
               
               
                   
                 polyphosphate 
                 retardant 
               
               
                 JLS-MC25 
                 Melamine cyanurate 
                 Non-halogen 
                 Hangzhou JLS 
               
               
                   
                 (CAS # 37640-57-6) 
                 flame 
                 Flame Retardants 
               
               
                   
                   
                 retardant 
                 Chemical Co., Ltd 
               
               
                 Melapur ® 
                 Melamine Cyanurate 
                 Non-halogen 
                 BASF 
               
               
                 MC15 
                 (CAS # 37640-57-6) 
                 flame 
               
               
                   
                   
                 retardant 
               
               
                 Cloisite ™ 
                 Quaternary ammonium 
                 Co-additive 
                 Southern Clay 
               
               
                 30B 
                 salt modified natural 
                   
                 Products 
               
               
                   
                 montmorillonite 
               
               
                   
                 nanoclay 
               
               
                 TEFLON ® 
                 Polytetrafluoro- 
                 Anti- 
                 DuPont 
               
               
                 6C 
                 ethylene 
                 dripping 
               
               
                   
                   
                 agent 
               
               
                 Jetfine ® 
                 Talc 
                 Co-additive 
                 Imerys Talc 
               
               
                 3CA 
               
               
                 Irganox ® 
                 50/50 blend of 
                 Heat 
                 Ciba 
               
               
                 B225 
                 trisarylphosphite and 
                 processing 
               
               
                   
                 sterically hindered 
                 stabilizers 
               
               
                   
                 phenolic antioxidant 
               
               
                 Joncryl ® 
                 Epoxy-functional 
                 Chain 
                 BASF 
               
               
                 4368 
                 styrene-acrylic 
                 extender 
               
               
                   
                 oligomer 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 Extruder Conditions 
               
            
           
           
               
               
               
            
               
                   
                 Extruder Type 
                   
               
               
                   
                 18 mm Leistitz twin screw extruder 
               
            
           
           
               
               
               
               
            
               
                   
                 Examples 
                 A-C, 1-2 
                 3-4 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Order of Addition 
                 All ingredients fed into the extruder 
                   
               
               
                   
                   
                 hopper except APP, with APP added 
               
               
                   
                   
                 downstream. 
               
            
           
           
               
               
               
               
            
               
                   
                 Zone 1 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 2 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 3 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 4 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 5 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 6 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 7 
                 190° C. 
                 190° C. 
               
               
                   
                 Zone 8 
                 190° C. 
                 190° C. 
               
               
                   
                 Main RPM 
                 500 
                 350 
               
               
                   
                 Side RPM 
                 209 
                 209 
               
               
                   
                 % load 
                  58 
                  58 
               
               
                   
                 Vacuum 
                 On 
                 On 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 4 
               
             
            
               
                   
               
               
                 Molding Conditions 
               
               
                 Molding Machine: Nissei 88 
               
            
           
           
               
               
               
               
            
               
                   
                 Examples 
                 A-C, 1-2 
                 3-4 
               
               
                   
                   
               
            
           
           
               
            
               
                 Drying Conditions before Molding: 
               
            
           
           
               
               
               
               
            
               
                   
                 Temperature (° C.) 
                 70 
                 70 
               
               
                   
                 Time (h) 
                 16 
                 4 
               
            
           
           
               
            
               
                 Temperatures: 
               
            
           
           
               
               
               
               
            
               
                   
                 Nozzle (° C.) 
                 210 
                 200 
               
               
                   
                 Zone 1 (° C.) 
                 204 
                 193 
               
               
                   
                 Zone 2 (° C.) 
                 199 
                 188 
               
               
                   
                 Zone 3 (° C.) 
                 199 
                 188 
               
               
                   
                 Mold (° C.) 
                 49 
                 27 
               
            
           
           
               
            
               
                 Speeds: 
               
            
           
           
               
               
               
               
            
               
                   
                 Screw RPM 
                 131 
                 65 
               
               
                   
                 Inj Vel Stg 1 
                 20% 
                 60% 
               
               
                   
                 Inj Vel Stg 2 
                 15% 
                 40% 
               
               
                   
                 Inj Vel Stg 3 
                 10% 
                 40% 
               
               
                   
                 Inj Vel Stg 4 
                  5% 
                 30% 
               
               
                   
                 Inj Vel Stg 5 
                  5% 
                 20% 
               
            
           
           
               
            
               
                 Pressures: 
               
            
           
           
               
               
               
               
            
               
                   
                 Injection Pressure 
                 8 
                 8 
               
               
                   
                 Stg1 - Time (sec) 
               
               
                   
                 Injection Pressure 1 
                 0 
                 90% 
               
               
                   
                 Hold Pressure 2 
                 90 
                 25% 
               
               
                   
                 Hold Pressure 3 
                 40 
                 0 
               
               
                   
                 Back Pressure 
                 5 
                  5% 
               
            
           
           
               
            
               
                 Timers: 
               
            
           
           
               
               
               
               
            
               
                   
                 Injection Hold (sec) 
                 8 
                 7 
               
               
                   
                 Cooling Time (sec) 
                 15 
                 20 
               
            
           
           
               
            
               
                 Operation Settings: 
               
            
           
           
               
               
               
               
            
               
                   
                 Shot Size (mm) 
                 43 
                 40 
               
               
                   
                 Cushion (mm) 
                 1.1 
                 1.1 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
               
             
               
                   
                 TABLE 5 
               
             
            
               
                   
                   
               
               
                   
                 Example 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                 A 
                 B 
                 C 
                 1 
                 2 
                 3 
                 4 
               
               
                   
                   
               
            
           
           
               
            
               
                 Ingredients (by weight % of compound) 
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Ultem ® 1000 
                   
                 100.0 
                   
                   
                   
                   
                   
               
               
                 Ultem ® 9085 
                   
                   
                 100.0 
               
               
                 PBS ENP01 G4560m 
                 100.0 
                   
                   
                 69.9 
                   
                 59.8 
                 59.8 
               
               
                 PBS ENP01 G4560J 
                   
                   
                   
                   
                 69.9 
               
               
                 Irganox ® B225 
                   
                   
                   
                 0.1 
                 0.1 
                 0.1 
                 0.1 
               
               
                 FP2200 
                   
                   
                   
                 24.2 
               
               
                 JLS-APP 
                   
                   
                   
                   
                 24.2 
                 29.2 
                 29.2 
               
               
                 Melapur MC-15 
                   
                   
                   
                 4.8 
               
               
                 JLS-MC25 
                   
                   
                   
                   
                 4.8 
                 4.8 
                 4.8 
               
               
                 Cloisite 30B 
                   
                   
                   
                 1.0 
                 1.0 
                   
                 5.0 
               
               
                 Jetfine ® 3CA 
                   
                   
                   
                   
                   
                 5.0 
               
               
                 DuPont TEFLON 6C 
                   
                   
                   
                   
                   
                 0.1 
                 0.1 
               
               
                 Joncryl 4368 
                   
                   
                   
                   
                   
                 1.0 
                 1.0 
               
               
                 Total 
                 100.0 
                 100.0 
                 100.0 
                 100.0 
                 100.0 
                 100.0 
                 100.0 
               
               
                   
               
            
           
         
       
     
     Samples were tested according to the procedures and test standards described below. 
     HDT (ASTM D648): was measured on the Tinius Olsen HDT from Tinius Olsen Inc (PA, USA) at heating rate of 20° C./min. Two measurements were made for each sample. 
     Notched Izod Impact (ASTM D-256) 
     Cone calorimetry: The cone calorimeter was used to measure the heat release and smoke release of these formulations, according to ASTM E1354-13. A square sample of 100 cm×100 cm was placed horizontally 25 mm below the radiant heat source, the cone. The heat flux used was 65 kW/m 2 . Upon exposure to the cone, a spark igniter was placed above the surface of the sample and the time to ignition is recorded. The time to flameout was also manually recorded, while the instrumentation measures the consumption of oxygen from the sample stream as well as the production of carbon monoxide and carbon dioxide. A laser placed across the exhaust duct measured the obstruction of the beam by the combustion products to output smoke measurements. 
     PCFC: The samples were tested with the MCC at 1° C./sec heating rate under nitrogen from 150° C. to 800° C. using method A of ASTM D7309 (pyrolysis under nitrogen). Each sample was run in triplicate to evaluate reproducibility of the flammability measurements. 
     
       
         
           
               
             
               
                 TABLE 6A 
               
             
            
               
                   
               
               
                 Test Results 
               
            
           
           
               
               
               
            
               
                 Example 
                 3 
                 4 
               
               
                   
               
               
                 Flex Modulus (KSI @ 0.5 in/min) 
                  234 ± 7.9 
                   246 ± 10.8 
               
               
                 Flex Strength (PSI @ 0.5 in/min) 
                 5576.8 ± 248.4 
                 5888.7 ± 55.6 
               
               
                 Tensile Modulus (KSI) @ 2 in/min 
                 192.7 ± 29.1 
                 283.4 ± 3.6 
               
               
                 Tensile Stength (PSI)@ 2 in/min 
                 3166.1 ± 147.3 
                 3369.4 ± 27.8 
               
               
                 Tensile Strain at Break (%)@ 2 in/min 
                 19.5 ± 3     
                  17.6 ± 1.6 
               
               
                 HDT @ 264 PSI 
                 56.9 ± 1.1 
                  58.8 ± 1.1 
               
               
                 Notched IZOD (ft · lb/in) 
                  0.6 ± 0.03 
                  0.47 ± 0.04 
               
               
                 Density (g/cm3) 
                 1.463 
                 1.448 
               
               
                 UL-94 @⅛″ 
                 V0 
                 V0 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 6B 
               
             
            
               
                   
               
               
                 Additional Flammability Tests 
               
            
           
           
               
               
               
               
               
            
               
                 Example 
                 1 
                 A 
                 B 
                 C 
               
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Cone 
                 Average HRR 
                 160.7 
                 N/A 
                 101.7 
                 119.1 
               
               
                 calorimetry 
                 (KW/m2) 
               
               
                   
                 Peak HRR 
                 217.8 
                 N/A 
                 251.2 
                 150 
               
               
                   
                 (KW/m2) 
               
               
                   
                 Total Smoke 
                 465.5 
                 N/A 
                 653.2 
                 782.4 
               
               
                   
                 (m2/m2) 
               
               
                   
                 Char Yield 
                 14.6 ± 0.2 
                  0.3 ± 0.1 
                  51.2 ± 0.5 
                 41.6 ± 0.4 
               
               
                   
                 (wt %) 
               
               
                   
                 HRR 
                    79 ± 56.6, 
                 545.1 ± 6.3 
               
               
                   
                 Peak(s)Value 
                 588 ± 49 
                   
                 312.4 ± 4.8 
                 202.7 ± 3.9  
               
               
                   
                 (W/g) 
               
               
                 PCFC 
                 HRR 
                 492.7 ± 1.2,  
                 427.3 ± 0.6 
               
               
                   
                 Peak(s)Temp(s) 
                 406 ± 1  
                   
                 567.6 ± 2.3 
                 516.4 ± 3.4  
               
               
                   
                 (° C.) 
               
               
                   
                 Total HR (kJ/g) 
                 17.2 ± 0.9 
                   20 ± 0.4 
                  8.8 ± 0.1 
                 10.9 ± 0.1 
               
               
                   
               
            
           
         
       
     
     Properties of the flame retardant polymer compound of the present invention are shown in Table 7. 
     
       
         
           
               
             
               
                 TABLE 7 
               
             
            
               
                   
               
               
                 Properties 
               
            
           
           
               
               
               
               
            
               
                   
                 Units 
                 Test Methods 
                 Value 
               
               
                   
                   
               
            
           
           
               
            
               
                 Physical 
               
            
           
           
               
               
               
               
            
               
                 Density 
                 g/cm 3   
                 ASTM D-792 
                 1.46 
               
               
                 Tensile Modulus 
                 GPa 
                 ASTM D-638 
                 1.3 
               
               
                 (2 in/min) 
               
               
                 Tensile Strength 
                 Mpa 
                 ASTM D-638 
                 22 
               
               
                 (2 in/min) 
               
               
                 Tensile Elongation 
                 % 
                 ASTM D-638 
                 19 
               
               
                 (2 in/min) 
               
               
                 Flexural Modulus 
                 GPa 
                 ASTM D-790 
                 1.6 
               
               
                 (0.5 in/min) 
               
               
                 Flexural Strength (0.5 
                 MPa 
                 ASTM D-790 
                 38.5 
               
               
                 in/min) 
               
               
                 Heat Deflection 
                 ° C. 
                 ASTM D-648 
                 57 
               
               
                 Temperature (264 psi) 
               
               
                 Notched Izod 
                 J/m 
                 ASTM D-256 
                 32 
               
               
                 Flammability (3 mm) 
                   
                 UL-94 
                 V0 
               
               
                 Glass Transition 
                 ° C. 
                 ASTM D3418 
                 74 
               
               
                 Temperature via DSC 
               
               
                 Melting Temperature 
                 ° C. 
                 ASTM D3418 
                 118 
               
               
                 via DSC 
               
               
                 Melt Flow Index 
                 (g/10 min) 
                 ASTM D1238 
                 29.3 
               
               
                 230° C./2.16 kg 
               
            
           
           
               
            
               
                 Injection Molding - Processing 
               
               
                 DRYING CONDITIONS 
               
            
           
           
               
               
               
               
            
               
                 Drying temperature 
                 ° C. 
                   
                 80 
               
               
                 Drying time 
                 hr 
                   
                 4 
               
            
           
           
               
            
               
                 MOLDING CONDITIONS 
               
            
           
           
               
               
               
               
            
               
                 Melt temperature 
                 ° C. 
                   
                 185-200 
               
               
                 Barrel temperature 
                 ° C. 
                   
                 185-200 
               
               
                 Mold temperature 
                 ° C. 
                   
                 25-30 
               
               
                 Maximum moisture 
                 % 
                   
                 0.05 
               
               
                 content