Title of Invention

A FLAME RETARDANT POLYMERIC COMPOSITION.

Abstract

The present invention relates to photsphorous containing flame retardant polymer composition and a arocess for their preparation. Accordingly, the present invention provides a flame retardant polyester composition prepared by insitu polymerization of at least one diol, at one dicarboxalic acid, at least one phosphorous compund as a flame retardant and at least one synergizer and optionally an antioxidant and a colorant.

Full Text

COMPLETE AFTER PROVISIONAL FORM-2 THE PATENT ACT, 1970 (39 of 1970) & THE PATENT RULES, 2003 COMPLETE SPECIFICATION (See section 10 and Rule 13) A FLAME RETARD ANT POLYMERIC COMPOSITION FUTURA POLYESTERS LIMITED An Indian Company of Paragon Condominium, 3r Floor, Pandurang Budhakar Marg, Mumbai-400 013, Maharashtra, India. THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED. Field of invention The present invention relates to flame retardant composition. In particular, the present invention relates to novel flame-retardant polymer compositions and method for preparing such compositions. Background of the invention Flame-retardants (FR) chemicals render combustible materials more resistant to ignition. The presence of FR minimizes the risk of a fire in case of contact with a small heat source such as cigarette, candle or an electrical fault. Even in case of a fire, the presence of a flame retardant slows down combustion and prevents fire from spreading. A wide variety of chemicals are used as flame-retardants. According to one of the classifications, the flame-retardants are categorized based on their contents such as: Nitrogen containing Minerals (based on aluminium and magnesium) containing Halogens (Bromine and Chlorine) containing, and Phosphorus containing etc. Typically, the nitrogen containing flame-retardants have lower efficiency and are useful only for certain specific polymers. Often, inorganic compounds like aluminum and magnesium hydroxides are added in large quantities to get the required activity. Flame-retardants acting chemically in the gas phase, particularly brominated compounds are most effective. However, based on the fire safety of products and its harmful effect on environment and health, their use is much regulated. Currently, therefore, non-halogen based flame-retardants such as Organic and Inorganic Phosphorous compounds are preferred. Non-halogenated phosphorous based flame-retardants have the advantage that they do not produce toxic halogenated dioxins and furans as well as corrosive smoke which are detrimental to the building and its associated sensitive equipments. The most important phosphorous-based flame-retardants include phosphate esters, phosphonates and phosphinates, red phosphorous and ammonium polyphosphate. Due to their advantageous properties, phosphorous-based flame-retardants are widely used in a variety of polymers including the engineering plastics, thermosets and textiles. There is considerable interest in use of flame-retardant polymers since polymers find applications in a variety of areas. Conventionally, the flame-retardant polymers are prepared by adding the appropriate flame-retardant material during processing of the polymer such as, for example, during extrusion etc. Published United States Patent Application No. 20040198878 discloses a flame retardant PTT resin composition comprising a mixture of phosphorous and nitrogen containing flame-retardants which are melt kneaded with PTT along with inorganic fillers and other additives, if necessary, using a single or multi screw extruder. Published United States Patent Application No. 20050256293 discloses flame-retardant resin compositions of PET, PTT, PBT, PTN comprising phosphorous-based biscumyl compound. United States Patent No. 6,617,379 discloses a combination of flame retardants like piperazinebis(neopentylglycol)phosphorous compound along with melamine as the co-additive for polyesters like PET, PTT, PBT etc. United States Patent No. 6,737,455 describes the feeding of resorcinol bis(diphenyl phosphate) or BPA-DP and glass fiber down-stream the extruder for obtaining the desired properties. Japanese Patent application No 2005015947 describes the use of resorcinol bis(diphenyl phosphate) as a self-emulsion dissolved in a water-soluble solvent and a small amount of water in the presence of an anionic surfactant and/or a nonionic surfactant for use as a flame retardant. The flame-retardant processing method comprises adding the flame-retardant processing agent to water with stirring, emulsifying and dispersing the agent into water to give a flame-retardant processing solution and immersing a polyester-based fiber in the solution by an immersion method or a continuous treatment method to adsorb RDP on the polyester-based fiber. Japanese Patent application No. 2004285226 provides a flame retardant PTT resin composition using a combination of phosphorous and nitrogen based flame retardants. Japanese Patent No. 2003292755 deals with flame retarded PTT resin composition consisting of a compound having mainly triazine rings along with inorganic filler. Japanese Patent No. 2003027369 provides a method for producing a flame retardant net having excellent flame proof properties at a low cost that has no adverse effect on the environment, etc., even though a flameproof agent is eluted from the net due to aged deterioration thereof. This method for producing the flame retardant net comprises immersing a net body during net making process in the flame retardant received in a tank, impregnating the net body with the flame retardant, removing an excess of the flame 4 retardant adhered to the net body with a squeezing means, and drying the net body to anchor the flame retardant agent to the net body, wherein at least one kind of compound selected from resorcinol bis(diphenyl phosphate). Japanese Patent No. 2000328445 describes process to perform durable flame-proof finishing of a polyester fiber with little deterioration of light-fastness by adding an emulsion composition containing a resorcinol bis(diphenyl phosphate) to a dyeing bath for a polyester fiber. Resorcinol bis(diphenyl phosphate) is dispersed in water in the presence of 2-30 wt.% (based on the resorcinol compound) nonionic surfactant such as polyoxyalkylene alkylphenyl ether and/or anionic surfactant such as an alkylsulfate salt. The obtained emulsion composition is added to a dyeing bath for a polyester fiber and a polyester fiber is dipped in the bath and subjected to the flame-proof treatment simultaneously with dyeing treatment at > 80 °C for 2-60 min to achieve the flame-proof finishing of the polyester fiber. United States Patent application no. 20060217469 discloses thermally stabilized phosphorous containing flame retardant agglomerates comprising at least one binder, one stabilizer to the phosphorous containing flame retardant. An International Patent Application No. WO 2006005716 discloses a curable composition that provides fire retardant, self extinguishing properties fro adhesive applications. The curable composition contains a particulate, phosphorous containing compound (preferably ammonium polyphosphate or triphenyl phosphate) and another compound which is a liquid phosphorous compound or particulate compound. 5 All the developments till date have made the polyester flame retardant by either compounding the additive with the polymer in an extruder or processing the fiber by a further step which is similar to the conventional finishing treatments. None of the prior art documents, suggest the addition of non halogen-free phosphorous based flame retardant, during the polymerization reaction itself. The additional operation of extruder blending or extra finishing step is avoided if the flame retardant additive is incorporated in the polymerization reaction itself as disclosed in the present invention. In selecting a Flame Retardant (FR) additive, one has to match up the decomposition temperature of flame retardant with the self ignition temperature of the polymer in addition to considering the thermal stability during processing, efficiency of flame retardant, its ultra-violet stability, non blooming tendency and the cost. Considering these requirements, amongst the phosphorous flame retardants, organo- Phosphorous compounds that act both in the vapor phase and condensed phase like Resorcinol & Bis-phenol-A phosphates are suitable and particularly Resorcinol Bis(diphenyl phosphate) (RDP) is ideally suited for polyesters. Other phosphorous flame retardants like ammonium phosphates, melamine pyrophosphates and polyphosphates acts only in the condensed phase and phosphorous flame retardants like triphenylphosphate act largely in vapor phase. Objects of the invention It is one of the objects of the present invention to provide a flame retardant polymer material. 6 It is another object of the invention to provide flame retardant polymer composition containing phosphorous compound. It is a further object of the present invention to provide a novel process for preparing a phosphorous containing flame retardant polymer composition. It is yet another object of the invention to produce polymer with phosphorus containing flame retardant additive, which has been incorporated in the polymerization reaction itself and therefore does not need any further processing. Summary of the invention The present invention relates to a phosphorous based flame retardant polyester resin composition for fiber spinning and molding applications. The flame retardant composition acts as an intumescent for suppressing the flammability. Intumescent products are those which expand (or intumesce) to several times their original size when activated by high temperatures. This action prevents the spread of flames and smoke to other parts of a building. A non-reactive synergizer in the form of a nanoparticle particularly nanosilica, nanoclay, etc. is also added in the polymerization reaction. The synergy that occurs between the phosphorous based flame retardant and the nano additives helps to reduce the loading of the phosphorous based flame retardant and thus reduce their negative effect on the properties of the compounds. The reactive and the non-reactive components add synergy to the flame retardation mechanism of intumescence. Non-reactive passive fire protection construction components are used to resist, retard and isolate flames and the associated smoke and fumes. They do not in themselves extinguish flames hence they are classed as 'passive protection'. 7 The addition of the flame retardant in the polymerization reaction eliminates a further step of processing the resin like coating of the fibers, filaments or fabrics with flame retardant or compounding with flame retardant through extruder. Elimination of one more processing stage is the novelty obtained when the phosphorus based flame retardant could be successfully added in the polymerization reaction without affecting the forward rate of polymerization reaction. The present invention relates to flame retardant polymer composition and a process for their preparation. Accordingly, the present invention provides a flame retardant polymeric composition consisting of dicarboxylic acid and diols in the ratio of 1:1 to 1:2 and intimately mixed with o a phosphorous containing compound in the range of 0.1 to 20 wt % based on the mass of reactants and o a synergiser compound in the range of 1000 ppm to 10000 ppm o and optionally comprising an antioxidant in the range of 0 ppm to 500 ppm o and optionally a colorant in the range of 0.1 ppm to 60 ppm In one of the embodiments, the dicarboxalic acid is selected from a group of dicarboxylic acids consisting of terephthalic acid, comprises terephthalic acid, naphthalene 1,2 dicarboxylate, ethanedionic acid, propanedionic acid, methanedionic acid, butanedionic acid, hexanedionic acid, heptanedionic acid, octanedionic acid and decanedionic acid. In another embodiment, the diol is selected from a group of diols consisting of 1,3-propane diol, ethylene glycol, 1, 4-butane diol, propylene glycol, cyclohexane dimethanol. 8 In another embodiment, the phosphorus compound is selected from a group of compound consisting of triaryl phosphate, e.g, resorcinol bis (diphenyl) phosphate and cresyl diphenyl phosphate. In another embodiment, the synergizer is at least one compound selected from a group of compounds consisting of nanosilica, nanocarbon tubes, fullerenes and nanoclay. Typically, phosphorus based compound is added in doses varying from 0.1 wt. % to 20 wt. % in the polymerization reaction. Preferably, the process the addition of a non reactive synergizer, specifically a nanoparticle, more specifically, nanosilica, nanoclay, etc., in the polymerization reaction in a concentration range of 1000 ppm to 10000 ppm, more preferably 3000 ppm to 5000 ppm. In yet another embodiment, the particle size of nanosilica and nanoclay is in the range of 60-90 nm. Typically, the intrinsic viscosity of the polyester made with ethylene glycol and terephthalic acid being 0.40 dL/g to 0.70 dL/g for the textile grade fibers/filaments and 0.70 dL/g to 1.00 dL/g for the technical grade filaments and molding applications. Again, typically, the intrinsic viscosity of the polyester made with 1,3-propane diol and terephthalic acid being 0.6 dL/g to 1.3 dL/g for the various textile and technical fibers and filaments and molding applications. As one of the embodiments, the composition is spinnable into textile grade fibers/filaments or can be process able into molds of desired shapes. 9 In accordance with another aspect of the invention there is envisaged the addition of a synergizer, a non reactive component which is necessary for the reactive component to synergize the flame retardancy by the process of intumescence through the reactive component. In accordance with yet another aspect of the invention, the incorporation of phosphorus based flame retardant additive is possible during the preparation of various polymers viz. polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) and polybutylene terephthalate (PBT). The phosphorous based compound used typically is resorcinol bis(diphenyl phosphate) (RDP) or cresyl diphenyl phosphate (CDP). Aromatic oligomeric phosphate ester flame retardants have high thermal stability and low volatility compared to the triaryl phosphates. The addition of these flame retardants was carried out at the end of polymerization reaction after purging the reactor with N2 under pressure. The reaction was further carried out for 10 to 30 minutes for the proper miscibility of the flame retardant in the molten polymer. Samples were evaluated for the flame-retardancy by ASTM D2863 test which evaluates the minimum concentration of oxygen that will just support flaming combustion in a flowing mixture of oxygen and nitrogen and reports the flame retardancy in volume percent. The value is also called as Limiting Oxygen Index (LOI). Few experiments were carried out by adding various flame retardants to the polymer at constant temperature and pressure. The phosphorous containing flame retardants like 2-Carboxyethyl (phenyl)phosphinic acid and Resorcinol Bis(diphenyl phosphate) were incorporated in the polymerization reaction of Polyethylene terephthalate (PET) and 10 Polytrimethylene terephthalate (PTT). The Limiting oxygen index of these polyester resins was tested and tabulated in Table 1. Table 1: Limiting Oxygen Index (LOI) of Various Flame Retardants Polyester Resin Flame Retardant FRppm level Limiting Oxygen Index,% PET - 21 2-carboxyethyl(phenyl)phosphinicacid 2500 30 Resorcinol Bis(diphenyl phosphate) 3500 29 PTT - 23 2-carboxyethyl(phenyl)phosphinicacid 2500 24 Resorcinol Bis(diphenyl phosphate) 3500 28 The results presented in Table 1 shows that addition or name retardant has worked better with PET and PTT polymer. It was observed that 2-Carboxyethyl (phenyl) phosphinic acid leached out of polyester fiber and therefore a large quantity of 2-Carboxyethyl (phenyl) phosphinic acid was needed during reaction, which made it unsuitable economically and chemically. Resorcinol Bis(diphenyl phosphate) was found to be the better FR for PET as well as PTT. Therefore, further experiments were carried out using Resorcinol Bis(diphenyl phosphate) as a phosphate containing flame retardant. The invention will now be explained more specifically by referring to the following examples. However, the present invention is not limited by these examples in any way. 11 Example 1 In a typical experiment for preparing the flame retardant polymer composition, 8.06 kg of terephthalic acid and 4.61 kg of 1,3-propane diol were taken in a reactor vessel. To this, 30 g of nanosilica having 30 % dispersion and of size 80 nm was added. The mixture was stirred for some time and then 2.7 g of phosphorus based antioxidant was added. This mixture was stirred at 20 rpm and at 240 to 250 °C temperature for about 3.5 hrs to obtain bis (hydroxy propylene terephthalate) as a product, which was further polymerized to poly(trimethylene terephthalate) by addition of 2.28 g tetra-n-butyl titanate. The polymerisation reaction was carried out at 260 to 285 °C for 2.5 hrs. At the end of the polymerization reaction, 0.40 kg of resorcinol bis(diphenyl phosphate) as the flame retardant compound (4 % by weight based on 10 kg final polymer weight) was added and the polymerization was continued further for 15 minutes to have uniform dispersion. The reaction was stopped by switching the stirrer off. The polymeric resin was filtered and converted into plaque. The flame retardancy was evaluated by ASTM D 2863, which gave LOI value of 28 %. Example 2 In another experiment for preparing the flame retardant polymer composition, 8.06 kg of terephthalic acid and 4.61 kg of 1,3-propane diol were taken in a reactor vessel. To this, 30 g of nanosilica having 30 % dispersion and of size 80 nm was added. The mixture was stirred for some time and then 2.7 g of phosphorus based antioxidant was added. This mixture was stirred at 20 rpm and at 240 to 250 ° C temperature for 3.35 hrs to obtain bis (hydroxy propylene terephthalate) as a product, which was further polymerized to poly(trimethylene terephthalate) by addition of 2.28 g tetra-n-butyl titanate. The polymerisation reaction was carried out at 265 to 285 °C for 2.00 hrs. 12 At the end of the polymerization reaction, 1.20 kg of resorcinol bis(diphenyl phosphate) as the flame retardant compound (12 % by weight based on 10 kg final polymer weight) was added and the polymerization was continued further for 15 minutes to have uniform dispersion. The reaction was stopped by switching the stirrer off. The polymeric resin was filtered and converted into plaque. The flame retardancy was evaluated by ASTM D 2863, which gave LOI value of 32 %. Example 3 In aother experiment for preparing the flame retardant polymer composition, 8.65 kg of terephthalic acid and 3.71 kg of ethylene glycol were taken in a reactor vessel. To this, 30 g of nanosilica having 30 % dispersion and of size 80 nm was added. The mixture was stirred for some time and then 2.22 g of phosphorus based antioxidant was added. This mixture was stirred at 20 rpm and at 250-260°C temperature for 3.5 hrs to obtain bis (hydroxy ethylene terephthalate) as a product, which was further polymerized to poly (ethylene terephthalate) by addition of 3.59 g antimony trioxide. The polymerisation reaction was carried out at 265 to 285 °C for 3.0 hrs. At the end of the polymerization reaction, 0.463 kg of resorcinol bis(diphenyl phosphate) as the flame retardant compound (4.63 % by weight based on 10 kg of final polymer weight) was added and the polymerization was continued further for 15 minutes to have uniform dispersion. The reaction was stopped by switching the stirrer off. The polymeric resin was filtered and converted into plaque. The flame retardancy was evaluated by ASTM D 2863, which gave LOI value of 32 %. 13 Example 4 The molar Ratio of Purified Terephthalic acid (PTA) and Monoethylene glycol (MEG) is 1:1.15. 8.65 kg of PTA and 3.7 kg of MEG are taken in a reactor vessel. To this, esterification and polymerization catalyst, Titanium dioxide 50 g (5000 ppm as Ti02), Diethylene glycol (DEG) suppressor, Sodium acetate trihydrate 7.00 g (700 ppm as such) and colorants, Cobalt acetate 2.1 g (50 ppm as Co), Red Toner 0.01 g (1 ppm as such) and Blue toner 0.01 g (1 ppm as such) are added to the reaction mixture. The esterification temperature is increased from 220 - 265 °C for a period of 300 minutes. The prepolymer formed is transferred to a polyreactor. To the prepolymer, 2.2 g of thermal stabilizer Triethylphosphonoacetate (TEPA, 30 ppm as P) and 3.5 g of polymerization catalyst Antimony trioxide (300 ppm as Sb) are added. The polymerization temperature is increased from 265 °C to 285 °C and the pressure is decreased from 1030 mbar to 4 mbar for a period of 80 minutes. After reaching the required molecular weight, 4.5 wt% of Resorcinol Bis(diphenyl phosphate) (RDP) is added. RDP was allowed to interact thoroughly with the melt for about 20 minutes. The amorphous polymer melt is then extruded under nitrogen pressure and collected as pellets. During esterification water is removed and during prepolymerization and polymerization excess glycol and reaction glycol are removed and the final polymer obtained will be 10 kg. It is customary to consider the batch weight based on final polymer weight and the additives in ppm are expressed based on the final polymer weight. Example 5 The molar ratio of Purified Terephthalic acid (PTA) and Monoethylene glycol (MEG) is 1:1.2 . 8.64 kg of PTA and 3.8 kg of MEG are taken in the reactor vessel. To this 50 g Titanium dioxide (5000 ppm as Ti02), 5 g Sodium acetate trihydrate (500 ppm as such), 2.1 g Cobalt acetate (50 ppm 14 as Co), 0.01 g Red Toner (1 ppm as such) and 0.01 g Blue toner (1 ppm as such) are added to the reaction mixture. The esterification temperature is increased from 220 - 265 °C for a period of 280 minutes. The prepolymer formed is transferred to a polyreactor. To the prepolymer, 2.2 g of Triethylphosphonoacetate (TEPA, 30 ppm as P) and of 3.5 g Antimony trioxide (300 ppm as Sb) are added. The polymerization temperature is increased from 265 °C to 290 °C and the pressure is decreased from 1030 mbar to 4 mbar for a period of 70 minutes. After reaching the required molecular weight, 3 wt% of Resorcinol Bis(diphenyl phosphate) (RDP) is added. RDP was allowed to interact thoroughly with the melt for about 20 minutes. The amorphous polymer melt is then extruded under nitrogen pressure and collected as pellets. Example 6 Molar Ratio of Purified Terephthalic acid (PTA) and Propane diol (PDO) is 1:1.2. 4.83 kg of PTA and 2.73 kg of PDO are taken in the reactor vessel. To this antioxidant, 1.5 g Octadecyl-3-(3,5-di-?-butyl-4-hydroxyphenyl)propionate (Irganox 1076, Ciba Specialty Chemicals Corporation, USA) (250 ppm as such), a non-reactive synergize, 18 g Nyacol® (Nanotechnologies, Inc., Austen, TX) (3000 ppm as such) and colorants, 0.5 g Cobalt acetate (20 ppm as Co), 0.006 g Red Toner (1 ppm as such) and 0.006 g Blue toner (1 ppm as such) are added to the reaction mixture. The esterification temperature is increased from 220 - 265 °C for a period of 220 minutes. The prepolymer formed is transferred to a polyreactor. To the prepolymer, 2.2 g of polymerization catalyst Tetrabutyl titanate (TnBT) (50 ppm as Ti), 3 g of glacial acetic acid (500 ppm, as such) and 2.1 g of Antimony trioxide (300 ppm as Sb) are added. The polymerization temperature is increased from 265 °C to 285°C and the pressure is decreased from 1030 mbar to 4 mbar for a period of 120 minutes. After 15 reaching the required molecular weight, 12 wt% of Resorcinol Bis(diphenyl phosphate) (RDP) is added. RDP was allowed to interact thoroughly with the melt for about 20 minutes. The amorphous polymer melt is then extruded under nitrogen pressure and collected as pellets. Here, ppm concentrations are based on 6 kg final polymer weight. Example 7 The resin composition is similar to Example 6 except for the addition of Nyacol. Esterification and polymerization are carried out under similar temperature and pressure. The total time taken for esterification is 200 minutes and polymerization is 120 minutes. The amorphous polymer is extruded under nitrogen pressure and collected as pellets. Table 2: Resin Composition of the Examples 1 to 7 Ingredients Example 1 Example2 Example3 Example4 Example5 Example 6 Example7 Batch weight 10 10 10 10 10 6 6 Molar ratio 1:1.2 1:1.2 1:1.15 1:1.15 1:1.2 1:1.2 1:1.2 Antioxidant 2-7 g 2-7 g 2.2 g 1.5 g 1.5 g 270 ppm as such 270 ppm as such 220 ppm as such 250 ppm as such 250 ppm as such Nyacol 30 g 30 g 18 g 3000 ppm as such 3000 ppm as such 3000 ppm as such Ti02 50 g 50 g 5000 ppm as Ti02 5000 ppm as Ti02 Sodiumacetatetrihydrate 7g 5g 700 ppm as such 500 ppm as such Co(OAc)2 2.1 g 2.1 g 0.5 g 0.5 g 50 ppm as Co 50 ppm as Co 20 ppm as Co 20 ppm as Co RT/BT 0.01 g 0.01 g 0.006 g 0.006 g 1 ppm as such 1 ppm as such 1 ppm as such 1 ppm as such 16 Ingredients Example 1 Example2 Example3 Example 4 Example5 Example 6 Example7 Sb203 3.5 g 3.5 g 3.5 g 2-1 g 2.1 g 300 ppm as Sb 300ppm as Sb 300ppm as Sb 300 ppm asSb 300 ppm asSb TnBT 2.28 g 2.28 g 2.2 g 2.2 g 30 ppm as Ti 30 ppm as Ti 50 ppm as Ti 50 ppm as Ti TEPA 2.2 g 2.2 g 30 ppm asP 30 ppm asP Additive FR (RDP) 400 g 1200 g 463 g 450 g 300 g 720 g 720 g 4wt% 12wt% 4.63 wt% 4.5 wt% 3 wt% 12wt% 12wt% Table 3: Characteristics of the Amorphous Polymer ExampleNo IV (dL/g) CarboxylNumber(meq/kg) DiethyleneGlycolwt% Dipropylene Glycol wt% L*CIELab a*CIELab b*CIELab Tg°C Tm°C Teh °C 4 0.448 4 0.71 - 72.1 -2.6 4 63 217 136 5 0.615 32 1.31 - 61.8 -2.6 2.4 73 251 141 6 0.654 28 - 1.52 69.8 -5.9 10.9 46 227 70 7 0.637 31 - 1.30 75.5 -4.4 18.5 43 227 70 The Limiting oxygen index (LOI) was measured in accordance with ASTM D2683 and are given in Table 4 below: Table 4: Limiting Oxygen Index values for final product Example No Polyester FR, wt% Limiting Oxygen Index, % 3 PET 4.63 32 4 4.5 28 5 3 25 1 PTT 4 28 2 12 32 6 12 32 7 12 29 11 The results presented in Table 4 shows that LOl of final product depends on the quantity of flame retardant. The LOI of PTT is more than PET. Comparing examples 6 and 7, wherein 12 wt % of flame retardant compound i.e. RDP is added to PTT polymer during the reaction, LOI of the final product wherein a non reactive synergize i.e. Nyacol was added to the PTT was observed to be 32% whereas in absence of Nyacol, LOI was found to be only 29%. This difference in LOI may be attributed to the synergetic effect between the non-reactive component, Nyacol and the reactive component, RDP. Example 3 with Nyacol and Example 4 without Nyacol also show a similar difference in LOI. The polyester thus obtained is made into knitted fabric by any known method. The vertical flammability and the inclined flammability of the knitted fabric were measured in accordance with ASTM D6413:1999 and Technical Bulletin 117 (California) and the results are shown in Table 5. Table 5: Flammability Tests for RDP added Polyethylene terephthalate (Knitted fabric made from Example 4 resin) Method Test Value Vertical flammability Melt length 130 mm Average time after flame1 0.0 Sec Average time after glow 0.0 Sec Inclined flammability Flame spread"' 0.0 Sec Flame extinguishing time 0.0 sec This test method is used to measure the vertical flame resistance of textiles. As a part of the measure of flame resistance, after-flame and afterglow characteristics are evaluated. The melt length is an indication of the extent of charring without flame propagation. The maximum char length of a 18 specimen shall not exceed 200 mm. The parameters like 1, 2, 3 & 4 have limits as follows: 1. The max. afterflame shall not exceed 10 seconds 2. The max. afterglow shall not exceed 15 seconds 3 & 4. Limits not specified. Thus, the present invention discloses a flame retardant polyester composition containing Polyethylene Terephthalate (PET), Polytrimethylene Terephthalate (PTT), Polybutylene Terephthalate (PBT) etc. characterized by its processability in terms of spinning into textile and technical grade fibers/filaments and molding into desired shapes for different applications, along with flame resistance. The composition contains halogen-free phosphorous-containing flameproof agents, along with a non-reactive synergizer, incorporated in the polyester features flame resistance of LOI > 28 % in thickness -1.6 mm and spin ability into fibers. While considerable emphasis has been placed herein on the steps of the preferred embodiments, it will be appreciated that many permutations and combinations of the process steps and the composition can be made and that many changes can be made in the preferred scheme without departing from the principles of the invention. These and other changes in the preferred process steps as well as other steps of the process of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. 19 We Claim: 1. A flame retardant polymeric composition consisting of dicarboxylic acid and diols in the range of 1:1 to 1:2, intimately mixed with a. at least one phosphorous containing compound in the range of 0.1 to 20 wt % based on the mass of composition and b. at least one synergiser compound in the range of 1000 ppm to 10000 ppm; c. optionally comprising an antioxidant in the range of 0 ppm to 500 ppm; and d. optionally comprising a colorant in the range of 0.1 ppm to 60 ppm 2. A flame retardant polymeric composition as claimed in claim 1, wherein the acid is at least one acid selected from a group of dicarboxylic acids consisting of terephthalic acid, dimethyl naphthalene 2, 6-dicarboxylate, benzene 1,2 dicarboxalic acid, ethanedionic acid, propanedionic acid, methanedionic acid, butanedionic acid, hexanedionic acid, heptanedionic acid, octanedionic acid and decanedionic acid. 3. A flame retardant polymeric composition as claimed in claim 1, wherein the diol is at least one diol selected from a group of diols consisting of 1,3-propane diol, 1, 4-butane diol, ethylene glycol, propylene glycol and cyclohexane dimethanol. 4. A flame retardant polymeric composition as claimed in claim 1, wherein the phosphorus compound is a compound selected from a group of compounds consisting of triaryl phosphate, e.g, resorcinol bis (diphenyl phosphate) and cresyl diphenyl phosphate. 20 5. A flame retardant polymeric composition as claimed in claim 1, wherein the synergizer is at least one compound selected from a group of compounds consisting of nanosilica, nanocarbon tubes, fullerenes and nanoclay. 6. A flame retardant polymeric composition as claimed in claim, wherein the particle size of synergizer used is in the range of 60-90 nm. 7. A flame retardant polymeric composition as claimed in claim 1, wherein the catalyst is at least one titanium based compound selected from a group of compounds consisting of tetra-n-butyl titanate, titanium dioxide and tetrabutyl titanate. 8. A process for making a flame retardant polymeric composition comprising the following steps, (a) adding predetermined quantities of dicarboxylic acid, diol and a titanium based catalyst in a reactor vessel along with optionally antioxidant, a non reactive synergizer and a colorant; (b) heating the reactor vessel to a temperature in the range of 200 °C to 270 °C for a period in the range of 200 minutes to 350 minutes to form a prepolymer; (c)transferring the prepolymer formed to a polyreactor; (d) adding further predetermined amounts of titanium based catalyst to the prepolymer and heating the polyreactor to a temperature in the range of 260 °C to 290 ° C at a pressure in the range of 1000 to 2 mbar for a time period in the range of 100 minutes to 200 minutes to obtain a molten polymer; (e) dispersing at least one phosphorous containing compound to the polymer in the range of 0.1 to 20 wt % based on mass of composition to form a flame retardant polymer composition; and 21 (f) extruding the flame retardant polymer composition under nitrogen pressure in the form of pellets. Dated this on 8l day of January 2007. Dewan of R. K. Dewan & Company Applicants' Patent Attorney 22 Abstract The present invention relates to phosphorous containing flame retardant polymer composition and a process for their preparation. Accordingly, the present invention provides a flame retardant polyester composition prepared by insitu polymerization of at least one diol, at least one dicarboxalic acid, at least one phosphorous compound as a flame retardant and at least one synergizer and optionally an antioxidant and a colorant. 8 JAiM 2007

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56-mum-2006-form 2(title page)-(6-4-2009).pdf

56-MUM-2006-FORM 2(TITLE PAGE)-(COMPLETE)-(8-1-2007).pdf

56-MUM-2006-FORM 2(TITLE PAGE)-(GRANTED)-(24-6-2009).pdf

56-MUM-2006-FORM 2(TITLE PAGE)-(PROVISIONAL)-(13-1-2006).pdf

56-MUM-2006-FORM 3(13-1-2006).pdf

56-MUM-2006-FORM 5(8-1-2007).pdf

56-mum-2006-form-26.pdf

56-MUM-2006-POWER OF ATTORNEY(6-4-2009).pdf

56-MUM-2006-SPECIFICATION(AMENDED)-(3-6-2009).pdf