Showing papers on "Triphenyl phosphate published in 1998"

Flame‐retardant properties of phenol–formaldehyde‐type resins and triphenyl phosphate in styrene–acrylonitrile copolymers

Abstract: The thermal and flame-retardant properties of phenol–formaldehyde-type resins (crosslinked and noncrosslinked) in mixtures with triphenyl phosphate and styrene–acrylonitrile resins were evaluated. The mixtures show a synergistic effect between triphenyl phosphate and novolacs. Those containing phenol–formaldehyde novolac resins are found to be most flame retardant. There does not seem to be a relationship between the oxygen index (OI) and UL 94 tests. Scanning electron microscopy analysis show a surface structure with cavities and stratification, very similar to that of intumescent additives. Evidence was found indicating that this flame-retardant system works in both the gas and condensed phase. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1067–1076, 1998

Pyrazolylborate)zinc Organophosphate Complexes Resulting from Hydrolytic Cleavage of Phosphate Esters

Abstract: Five different (pyrazolylborate)zinc hydroxide complexes Tp*Zn−OH (1) were used as hydrolytic reagents towards esters of various acids of phosphorus. Trimethyl phosphate and trimethyl phosphite could not be cleaved. Dimethyl and diphenyl phosphite yielded TptBu,MeZn−OPHO(OR) (2, 3). Triphenyl phosphate reacted slowly producing moderate yields of Tp*Zn−OPO(OPh)2 (4). Tris(p-nitrophenyl) phosphate was cleaved rapidly, forming Tp*Zn−OPO(OC6H4NO2)2 (5) and Tp*Zn−OC6H4NO2 (6). Alkylbis(p-nitrophenyl) phosphates showed intermediate reactivity, losing p-nitrophenolate upon hydrolysis and producing Tp*Zn−OPO(OR)(OC6H4NO2) (7, 8). When phosphorus acid diesters were employed, condensation between the Zn−OH and P−OH functions occurred. This proved to be the convenient way of preparing the organophosphate complexes Tp*Zn−OPO(Ph)2 (9), Tp*Zn−OPO(OPh)2 (4), and Tp*Zn−OPO(OC6H4NO2)2 (5). Six structure determinations showed the structural variability of the resulting complexes.

Interactions between Phosphorus-and Nitrogen-Containing Flame Retardants

Abstract: A halogen-free, flame-retardant polystyrene containing polyphenylene ether (PPE) with excellent melt flow, impact resistance, and heat resistance can be obtained through concurrent use of hydroxyphenyl-containing phosphate (resorcinyl diphenyl phosphate: triphenyl phosphate (TPP)-OH) as phosphorus-containing flame retardant and melamine cyanurate (MC) as nitrogen-containing flame retardant. Investigation of interactions between these two flame retardants showed that an intumescent process, which involves the formation of char that swells and foams, occurs upon the burning of this resin composition and lowers the burning surface temperature by 130°C compared with the resin composition without MC, in which the intumescent process does not occur. The resin composition containing TPP-OH/MC has higher impact resistance than that containing TPP/MC (TPP: contains no hydroxyl group). Viscoelastic measurement indicated significant interactions between TPP-OH and MC, including particularly hydrogen bonding between their hydroxyl and amino groups, which suggests that TPP-OH acts as a compatibilizer of MC.

Combustion and fire retardance of poly(2,6‐dimethyl–1,4‐phenylene ether)–high‐impact polystyrene blends. II. Chemical aspects

Abstract: The chemical reactions occurring during the intumescent process taking place in the combustion of the poly(2,6-dimethyl-1,4-phenylene ether )-high-impact polystyrene blends (PPE-HIPS) are studied in detail through the chemical characterization of the burnt and original material by infrared, pyrolysis-gas chromatographymass spectrometry, and direct insertion probe spectrometry. Evidence is given of thermal rearrangement in the blend of the polyether PPE chains to polybenzylic structures occurring in the heating conditions of pyrolysis or combustion, as previously shown, to take place in thermal degradation of PPE. The rearranged chain segments are shown to give a larger contribution to the intumescent char, while volatile blowing products are mostly formed by polystyrene and polybutadiene components. From PPE-HIPS blends, the volatilization of the fire-retardant triphenyl phosphate (TPP), which when heated alone volatilizes at a temperature below that of PPE-HIPS degradation, is delayed probably by hydrogen bonding with PPE. This allows TPP to play the typical flame inhibition role of volatile phosphorus compounds. Moreover, it is found that TPP favors the PPE rearrangement and henceforth increases the char yield of the burning blend, which is a typical condensed phase fire-retardant action.

Lithium ion secondary battery and its manufacture

Abstract: PROBLEM TO BE SOLVED: To suppress the deterioration of capacity and decrease the number of charge/discharge cycles of a battery by adding phosphoric ester as a surface active agent to at least one of a positive electrode material layer mainly comprising a lithium-containing composite oxide and a negative electrode material layer mainly comprising a carbon material. SOLUTION: Phosphoric ester acting as a surface active agent is added to at least one of a positive electrode material layer and a negative electrode material layer of a lithium ion secondary battery in which the positive electrode material layer mainly comprising a lithium-containing composite oxide (lithium cobaltate) and the negative electrode material layer mainly comprising a carbon material (graphite) absorbing/releasing lithium ions are stacked through a nonaqueous electrolyte layer. As the phosphoric ester, triphenyl phosphate or tricresyl phosphate is used and the adding amount is 2-20 wt.% based on the weight of the lithium-containing composite oxide or the carbon material. The phosphoric ester is eluted on the electrode surface, forms the unevenness on the electrode surface, and sufficiently heightens the wettability on the electrode surface. COPYRIGHT: (C)1999,JPO

Polyester composition for molding product having transparency and flame resistance

Abstract: PROBLEM TO BE SOLVED: To obtain the subject composition having flame resistance imparted without preventing the transparency of a polyester resin for a transparent molding material by formulating a an organic phosphorus compound having a specific structure with the polyester resin. SOLUTION: The subject composition is obtained by formulating (B) an organic phosphorus compound of the formula (R to R are each 6-20C aromatic hydrocarbon residue) with (A) a polyester resin for a transparent molding product (e.g. polyethylene terephthalate modified by 1,4-cyclohexanedimethanol). The component B is preferably triphenyl phosphate, tricresyl phosphate and tris(2,6-dimethylphenyl) phosphate. The component B is preferably formulated in an amount of 0.5-20 pts.wt. based on 100 pts.wt. component A.

Production of phosphate esters

Abstract: A process for the production of liquid meta-rich triaryl phosphate esters having low triphenyl phosphate content and low viscosity comprises (a) an alkylation stage wherein a phenol is reacted with an olefin having 2 to 12 carbon atoms in the presence of a strong acid catalyst to give a reaction product comprising a mixture of meta and para alkylated phenols; and (b) a transalkylation stage wherein the mixture of alkylated phenols from the alkylation stage is heated in the presence of a strong acid catalyst to increase the meta isomer content of the mixture to at least 25% whilst maintaining a phenol level below 22%; and (c) a phosphorylation stage wherein the mixture of alkylated phenols from the transalkylation stage is reacted with a phosphorylating agent; and wherein the strong acid catalyst used in stages (a) and (b) is a Bronsted acid having an acid strength of less than zero. Preferred catalysts are activated clays such as bentonite, montmorillonite or Fullers Earth clay. The alkylation and transalkylation are conducted at temperatures between 100° C. and 200° C., preferable 150° C. and 180° C.

Flame-retardant thermoplastic resin composition improved in resistances to moisture and heat

Abstract: PROBLEM TO BE SOLVED: To obtain a flame-retardant thermoplastic resin compsn. improved in resistances to moisture and heat by compounding a thermoplastic resin, an inorg. filler surface-treated with a phosphoric ester having a group having a free-radical-polymerizable ethylenic double bond, and an arom. orthophosphoric ester each in a specified amt. SOLUTION: A surface-treated inorg. filler is prepd. by mixing 0.01-10 pts.wt. phosphoric ester represented by the formula (wherein R is a 5-60C org. group having a free-radical-polymerizable ethylenic double bond; and l is 1 or 2) [e.g. mono(2-methacryloyloxyethyl) acidphosphate] with 100 pts.wt. inorg. filler in the form of a powder, rods, plates, etc., in an org. solvent (e.g. toluene) and removing the solvent by distillation. Then, 100 pts.wt. thermoplastic resin (e.g. a styrene resin), 5-100 pts.wt. surface-treated inorg. filler, and 5-50 pts.wt. arom. orthophosphoric ester (e.g. triphenyl phosphate) are compounded and kneaded, e.g. on a hot roll, to give the objective resin compsn.

Clear resin film and its production

Abstract: PROBLEM TO BE SOLVED: To obtain a clear resin film which hardly curls in all the humidity range and is used in photography or for protecting polarized plates by dissolving a clear resin (e.g. cellulose acetate) and a plasticizer in a solvent which contains a good common solvent for the resin and the plasticizer, the common solvent having a b.p. higher than the m.p. of the plasticizer and contg. a specified amt. of a cyclic diether compd., and then forming the resultant soln. into a film by casting followed by drying. SOLUTION: The soln. contains a clear resin, 2-20wt.% (based on the resin) plasticizer, and 10-50wt.% (based on the resin) solvent. The solvent contains at least 70wt.% common solvent, of which at least 10wt.% is a cyclic diether represented by the formula (wherein R1 to R6 are each H, an alkyl, etc.). Examples of the clear resin are cellulose triacetate, cellulose propionate, nitrocellulose, a polycarbonate, and polystyrene. Pref. the resin is cellulose triacetate; the plasticizer is triphenyl phosphate; and the good solvent having a b.p. higher than the m.p. of the plasticizer is 1,3-dioxolane.

Fire-resistant thermoplastic resin composition and molding thereof

Abstract: PROBLEM TO BE SOLVED: To obtain a molding having an improved staining without losing its fire-resistance and mechanical strength by blending specific amounts of a polycarbonate resin, a phosphoric ester compound and a sulfonic acid phosphonium salt. SOLUTION: This composition comprises 100 pts.wt. of a polycarbonate resin, 0.5-30 pts.wt. of a phosphoric ester of formula I such as triphenyl phosphate or the like, 0.0001-10 pts.wt. of a sulfonic acid phosphonium salt of formula II such as dodecyl sulfonic acid tetraalkylphosphonium salt or the like, optionally not more than 200 pts.wt of at least one thermoplastic resin selected from the group consisting of a styrene resin, an acrylic resin and the like, and 0.0001-1 pt.wt. of a phosphorus stabilizer. In formula I, R R4 are each hydrogen or an organic group; X is an organic group whose valence state is not less than two; p is 0 or 1; q is 1-30; r is 0 or more. In formula II, R is a 1-40C alkyl or a 6-40C aryl; R , R and R are each hydrogen, a 1-10C alkyl or a 6-10C aryl.