×

Flame resistant polyester compositions, method of manufacture, and articles thereof

  • US 8,716,378 B2
  • Filed: 06/29/2010
  • Issued: 05/06/2014
  • Est. Priority Date: 06/29/2010
  • Status: Expired due to Fees
First Claim
Patent Images

1. A thermoplastic polyester composition comprising, based on the weight of the composition, a chlorine- and bromine-free combination of:

  • (a) from 40 to 60 wt % of poly(butylene terephthalate);

    (b) from 25 to 35 wt % of a glass fiber filler;

    (c) from 2 to 8 wt % of a flame retardant synergist selected from the group consisting of melamine polyphosphate, melamine cyanurate, melamine pyrophosphate, melamine phosphate, and combinations thereof;

    (d) from more than 10 to 15 wt % a phosphinate of formula (I)
    [(R1)(R2)(PO)—

    O]

    mMm+



    (I),a diphosphinate of formula (II)
    [(O—

    POR1)(R3)(POR2

    O)]2−

    nMm+x



    (II), and/ora polymer derived from the phosphinate of formula (I) or the diphosphinate of the formula (II),wherein R1 and R2 are identical or different and are H, linear or branched C1-C6 alkyl, or C6-C10 aryl;

    R3 is C1-C10, linear or branched alkylene, C6-C10 arylene, C7-C11 alkylarylene, or C7-C11 arylalkylene;

    M is an alkaline earth metal, alkali metal, Al, Ti, Zn, Fe, or B;

    m is 1, 2, 3 or 4;

    n is 1, 2, or 3; and

    x is 1 or 2;

    (e) at least 1% to less than 5 weight % of impact modifier component comprising a combination of (i) a poly(ether-ester) elastomer and (ii) a core-shell (meth)acrylate impact modifier;

    wherein the poly(ether-ester) elastomer comprises long-chain ester units of formula (III);


    -GOCOR′

    COO—





    (III);

    and short-chain ester units having units of formula (IV);


    -DOCOR′

    COO—





    (IV),wherein R′

    is a divalent aromatic radical remaining after removal of carboxyl groups from terephthalic acid, isophthalic acid, or a combination of terephthalic acid and isophthalic acid;

    G is a divalent polyalkylene oxide radical remaining after removal of terminal hydroxyl groups from a poly(alkylene oxide) glycol having a number-average molecular weight of 100 to 2500; and

    D is a divalent alkylene radical remaining after removal of hydroxyl groups from aliphatic diols having a molecular weight from 62 to 286; and

    wherein the core-shell meth(acrylate) impact modifier has a crosslinked poly(butyl acrylate) core with a grafted poly(methyl methacrylate) shell;

    (f) from more than 0 to 5 wt % poly(tetrafluoroethylene) encapsulated by a styrene-acrylonitrile copolymer; and

    (g) from more than 0 wt % to 2 wt % of a stabilizer;

    wherein the thermoplastic polyester composition contains 0 to less than 3 wt % of a polyetherimide; and

    wherein an article molded from the composition exhibits(a) a flexural modulus that is more than 9800 to less than or equal to 20000 MPa, measured in accordance with ASTM D790,(b) a flexural stress that is more than 150 to less than or equal to 190 MPa, measured in accordance with ASTM D790,(c) an unnotched impact strength that is more than 470 to less than or equal to 700 Joules/meter, measured at 23°

    C. in accordance with ASTM D256, and(d) a V0 rating at 0.8 mm, measured in accordance with UL 94.

View all claims
  • 4 Assignments
Timeline View
Assignment View
    ×
    ×