KR20000035969A - Blends containing an interpolymer of alpha-olefin - Google Patents

Abstract

PURPOSE: Blends containing an interpolymer of alpha-olefin are provided which have improved properties when compared to the individual polymers comprising the blend and provide materials with enhanced process ability and temperature ranges of performance. CONSTITUTION: The blends of polymeric materials comprise: (A) from about 1 to about 99weight percent of at least one interpolymer containing (1) from about 1 to about 65 mole percent of (a) at least one vinylidene aromatic monomer, or (b) at least one hindered aliphatic vinylidene monomer, or (c) a combination of at least one vinylidene aromatic monomer and at least one hindered aliphatic vinylidene monomer, and (2) from about 35 to about 99 mole percent of at least one aliphatic α-olefin having from 2 to about 20 carbon atoms; and (B) from about 1 to about 99 weight percent of at least one homopolymer or interpolymer of one or more vinylidene aromatic monomers and/or one or more hindered aliphatic vinylidene monomers.

Description

Blend containing an interpolymer of alpha-olefins {BLENDS CONTAINING AN INTERPOLYMER OF ALPHA-OLEFIN}

General classes of materials included in the substantially irregular interpolymers of α-olefin / hindered vinylidene monomers, including materials such as α-olefin / vinyl aromatic monomer interpolymers, are known in the art and these are described in US Pat. No. 5,460,818 It provides a variety of material structures and properties useful for a variety of applications, such as compatibilizers for blends of polyethylene and polystyrene as described.

D'Anniello et al., Journal of Applied Polymer Science, Vol. 58, pp. 1701-1706 (1995), is that such interpolymers can exhibit excellent elastic and energy scattering characteristics. In another aspect, certain interpolymers may be useful in adhesive systems, as described in US Pat. No. 5,244,996 to Mitsui Petrochemical Industries Ltd.

While useful in their own right, efforts are being made to improve the applicability of these interpolymers in the industry. Such improvement may be achieved by an additive or the like, but it is desirable to develop a technique that improves processability or performance without adding an additive, or provides an improvement effect that is greater than that obtained when adding an additive. To date, no possible benefit of blending that provides better properties has been found.

Materials that are based on α-olefin / vinylidene aromatic monomer interpolymers need to provide superior performance characteristics over unmodified polymers, which will further extend the utility of this class of materials of interest.

The present invention relates to blends of α-olefin / hindered vinylidene monomer interpolymers and vinyl aromatic polymers; Foams produced therefrom; And foams made from only α-olefin / hindered vinylidene monomer interpolymers. Blend components and ratios thereof were chosen to provide good performance and / or processability.

The present invention

(A) (1) (a) at least one vinylidene aromatic monomer, or (b) at least one hindered aliphatic vinylidene monomer, or (c) at least one vinylidene aromatic monomer and at least one hindered aliphatic vinylidene monomer. A combination of about 1 to about 65 mole%, and (2) about 1 to about 99 weight% of at least one interpolymer comprising about 35 to about 99 mole% of at least one aliphatic α-olefin having 2 to about 20 carbon atoms. ; And

(B) at least one homopolymer of (1) at least one vinylidene aromatic monomer, or (2) at least one interpolymer of at least one vinylidene aromatic monomer and / or at least one hindered aliphatic vinylidene monomer, or (3) about 1 to about 99 weight percent of one or more of (1) and (2), or (4) a combination of two or more of (1), (2) and (3), further containing an impact modifier

It relates to a blend of polymeric materials comprising.

The invention also

(I) at least one blowing agent; And

(II) (A) (1) (a) at least one vinylidene aromatic monomer, or (b) at least one hindered aliphatic vinylidene monomer, or (c) at least one vinylidene aromatic monomer and at least one hindered aliphatic About 1 to about 65 mole% of a combination of vinylidene monomer, and (2) about 1 to about 1 mole of at least one interpolymer comprising about 35 to about 99 mole% of at least one aliphatic α-olefin having 2 to about 20 carbon atoms. 100 wt%; And (B) a homopolymer of at least one vinylidene aromatic monomer and / or at least one hindered aliphatic vinylidene monomer, or at least one vinylidene aromatic monomer and / or at least one hindered aliphatic vinylidene monomer and optionally said vinyl One or more interpolymers or interpolymer blends comprising 0 to about 95.5% by weight of one or more interpolymers of at least one polymerizable ethylenically unsaturated monomer that is not a lidene aromatic monomer or a hindered aliphatic vinylidene monomer

It relates to a foamable composition comprising a.

Blends and foamable materials of the present invention may comprise, consist essentially of, or consist of two or more of the interpolymers listed herein. Likewise, the interpolymer may comprise, consist essentially of, or consist of two or more of the polymerizable monomers listed herein.

Such blends improve one or more polymer properties such as, but not limited to, mechanical performance and / or meltability.

The term "interpolymer" as used herein refers to a polymer in which two or more different monomers are polymerized to form a copolymer.

As used herein, the term "substantially irregular" in substantially irregular interpolymers comprising α-olefins and vinylidene aromatic monomers or hindered aliphatic vinylidene monomers indicates that the distribution of monomers of the interpolymers is Bernoulli statistics. It can be explained by a mathematical model or by a first- or second-order Markovian statistical model (JC Randall et al. Polymer Sequence Determination, Carbon-13 NMR Method, Academic Press New York). , 1977, pp. 71-78). Preferably, substantially irregular interpolymers comprising α-olefins and vinylidene aromatic monomers contain up to 15% total vinylidene aromatic monomer in a block composed of more than three vinylidene aromatic monomer units. More preferably, the interpolymer is not characterized by high isotacticity or syndiotacticity. This is due to the fact that the area of the peaks corresponding to the backbone methylene and methine carbons representing the meso diad sequence or racemic diad sequence in the 13C-NMR spectrum of the substantially irregular interpolymer is the backbone methylene and methine. It should not exceed 75% of the total peak area of carbon.

The numerical values referred to herein include all values from the lower limit to the upper limit in increments of one unit, with a difference of at least two units between any lower value and any higher value. By way of example, if the amount of a component or the value of a process variable (eg temperature, pressure time, etc.) is said to be 1 to 90, preferably 20 to 80, more preferably 30 to 70, this is 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc. means clearly listed herein. For values less than 1, one unit is considered to be 0.0001, 0.001, 0.01 or 0.1 as the case may be. These are only examples of what is specifically intended, and all possible combinations of numerical values between the lowest and highest enumerated values should be considered to be expressly described in this application in a similar manner.

Interpolymers suitable for use as component (A) for preparing blends comprising the present invention are prepared by polymerizing at least one α-olefin with at least one vinylidene aromatic monomer and / or at least one hindered aliphatic vinylidene monomer. Including but not limited to prepared interpolymers.

Examples of suitable α-olefins are α-olefins having 2 to about 20 carbon atoms, preferably 2 to about 12 carbon atoms, more preferably 2 to about 8 carbon atoms. Especially preferred are ethylene, propylene, butene-1, 4-methyl-1-pentene, hexene-1 and octene-1.

Examples of suitable vinylidene aromatic monomers are those represented by the following formula (I):

Where

R ¹ is selected from the group consisting of hydrogen and alkyl radicals having 1 to about 4 carbon atoms, preferably hydrogen or methyl;

Each R ² is independently selected from hydrogen and alkyl radicals having 1 to about 4 carbon atoms, preferably hydrogen or methyl;

Ar is a phenyl group or with one or more groups selected from halo, C _1-4 - alkyl and C _1-4 - a phenyl group substituted with 1 to 5 substituents selected from the group consisting of haloalkyl;

n has a value of 0 to about 6, preferably 0 to about 2, more preferably 0.

Examples of monovinylidene aromatic monomers include styrene, vinyl toluene, α-methylstyrene, t-butyl styrene, chlorostyrene and all isomers of these compounds. Particularly suitable such monomers are styrene and lower alkyl- or halo-substituted derivatives thereof. Preferred monomers include styrene, α-methyl styrene, lower alkyl- or phenyl-substituted derivatives of styrene (eg ortho-, meta- and para-methylstyrene), ring halogenated styrenes, para-vinyl toluene or their Mixtures and the like. More preferred monovinylidene aromatic monomer is styrene.

The term “hindered aliphatic or cycloaliphatic vinylidene monomers” refers to addition polymerizable vinylidene monomers corresponding to Formula II:

Where

Al is a steric bulky aliphatic substituent having up to 20 carbon atoms;

R ¹ is selected from the group consisting of hydrogen and alkyl radicals having 1 to about 4 carbon atoms, preferably hydrogen or methyl;

Each R ² is independently selected from hydrogen and alkyl radicals having 1 to about 4 carbon atoms, preferably hydrogen or methyl;

Alternatively, R ¹ and Al together form a ring system.

The term "sterically bulky" means that the monomers containing the substituents are not capable of addition polymerization by standard Ziegler-Natta polymerization catalysts at rates generally comparable to ethylene polymerization. Preferred hindered aliphatic or cycloaliphatic vinylidene monomers are those in which one of the ethylenically unsaturated carbon atoms is tertiary or quaternary substituted. Examples of such substituents are cyclohexyl, cyclohexenyl, cyclooctenyl, or their ring alkyl or aryl substituted derivatives, tert-butyl, norbornyl and the like. Most preferred hindered aliphatic vinylidene compounds are various isomeric vinyl-cyclic substituted derivatives of vinyl cyclohexene, cyclohexene and substituted cyclohexane, and 5-ethylidene-2-norbornene. In particular, vinyl cyclohexane is suitable.

Interpolymers of one or more α-olefins and one or more monovinylidene aromatic monomers and / or one or more hindered aliphatic or cycloaliphatic vinylidene monomers used in the present invention are substantially irregular polymers. These interpolymers are generally from about 1 to about 65 mole percent, preferably from about 5 to about 60 mole percent, more preferably from about 10 to one or more vinylidene aromatic monomers and / or hindered aliphatic or cycloaliphatic vinylidene monomers. About 55 mole%; And about 35 to about 99 mol%, preferably about 40 to about 95 mol%, more preferably about 45 to about 90 mol%, of at least one aliphatic α-olefin having 2 to about 20 carbon atoms.

The number average molecular weight (M _n ) of these interpolymers is generally greater than about 1,000, preferably about 5,000 to about 1,000,000, more preferably about 10,000 to about 500,000.

The present invention provides a blend of interpolymer components having a molecular weight and composition distribution selected such that the overall molecular weight and composition distribution provide improved properties or processability.

The blends of the invention comprise about 1 to about 99 weight percent of component (A), preferably about 3 to about 97 weight percent, more preferably about 5 to about 95 weight percent; And from about 1 to about 99 weight percent of component (B), preferably from about 3 to about 97 weight percent, more preferably from about 5 to about 95 weight percent. In some cases about 35 to about 99 weight percent of component (A), preferably about 40 to about 97 weight percent, more preferably about 60 to about 95 weight percent; And blends of the present invention which contain about 1 to about 65 weight percent of component (B), preferably about 3 to about 60 weight percent, more preferably about 5 to about 40 weight percent, in some cases they are This is because it exhibits much improved properties compared to blends containing less than about 35% of component (A).

When preparing component (A) which is a substantially irregular interpolymer, as described later, the homopolymerization of vinylidene aromatic monomers may result in the formation of an amount of atactic vinylidene aromatic homopolymer. In general, the higher the polymerization temperature, the more homopolymers are formed. The presence of vinylidene aromatic homopolymers is generally harmless in the present invention and may be acceptable. Vinylidene aromatic homopolymers may be separated from the interpolymers by extraction techniques such as optionally precipitation from solution using a non-solvent for the interpolymer or vinylidene aromatic homopolymer. In the present invention, vinylidene aromatic homopolymer is present in the interpolymer blend component in an amount of up to 20% by weight, preferably less than 15% by weight, based on the total amount of the interpolymer.

Substantially irregular interpolymers can be modified by typical grafts, hydrogenation, functionalization or other reactions known to those skilled in the art. The polymer may also be easily sulfonated or chlorinated according to established techniques to provide functionalized derivatives.

Substantially irregular interpolymers may be prepared as described in US Patent Application No. 545,403 (corresponding to European Patent Application No. 0,416,815) filed July 3, 1990 by James C. Stevens et al. These are incorporated herein by reference. The conditions for carrying out such a polymerization reaction are a pressure of 1 to 300 atm and a temperature of -30 ° C to 200 ° C. Polymerization and removal of unreacted monomers at temperatures above the autopolymerization temperature of the individual monomers may result in the formation of some amount of homopolymer polymerization product as a result of free radical polymerization.

Examples of suitable catalysts and methods for their preparation for preparing substantially irregular interpolymers are described in U.S. Patent Application No. 545,403, filed Jul. 3, 1990 (European Patent EP-A 416,815). ); US Patent Application No. 702,475, filed May 20, 1991 (European Patent EP-A 514,828); US Patent Application No. 876,268, filed May 1, 1992 (European Patent EP-A 520,732); US Patent Application No. 241,523, filed May 12, 1994; As well as US Pat. No. 5,055,438; No. 5,057,475; 5,096,867; 5,096,867; 5,064,802; 5,064,802; No. 5,132,380; 5,189,192; 5,189,192; 5,321,106; 5,321,106; 5,347,024; 5,347,024; No. 5,350,723; No. 5,374,696; And 5,399,635.

Substantially irregular α-olefin / vinylidene aromatic interpolymers are also described in detail by John G. Bradfute (WR Grace & Co.), which is also incorporated herein by reference. Patent Publication No. WO 95/32095; International Patent Publication No. WO 94/00500 to R.B. Pannell (Exxon Chemical Patents, Inc.); And Plastics Technolgy, p. 25 (September 1992).

Substantially having one or more α-olefin / vinyl aromatic / vinyl aromatic / α-olefin tetrads disclosed in the co-pending application by Francis J.Timmers et al. Irregular interpolymers are also suitable. These interpolymers contain additional signals that have an intensity that is at least three times the peak-to-peak noise. These signals are present in the chemical shift range of 43.75 to 44.25 ppm and 38.0 to 38.5 ppm. Specifically, main peaks are observed at 44.1, 43.9 and 38.2 ppm. Bound proton test (APT) NMR experiments show that the signal in the chemical shift range of 43.75 to 44.25 ppm is methine carbon and the signal in the range of 38.0 to 38.5 ppm is methylene carbon.

To measure the carbon-13 NMR chemical shifts of these interpolymers, the following procedures and conditions are used. 5-10% by weight of the polymer solution comprises 50% by volume of 1,1,2,2-tetrachloroethane-d ₇ and 50% by volume of 0.1 mole of chromium tris (acetylaceto in 1,2,4-trichlorobenzene Nate). NMR spectra are obtained at 130 ° C. using an inverse gated decoupling sequence, 90 ° pulse width and a pulse delay of at least 5 seconds. The spectrum is referred to as the isolated methylene signal of the polymer at 30,000 ppm.

These new signals may be produced before or after the insertion of one or more α-olefins, for example ethylene / styrene / styrene / ethylene tetrad, wherein the styrene monomer insertion of the tetrad takes place exclusively with the 1,2 (head to tail) technique. It is believed to be due to the sequence involving the two head-to-tail vinyl aromatic monomers of. Those skilled in the art have found that for such tetrades involving vinyl aromatic monomers different from styrene and α-olefins different from ethylene, the α-olefin / vinyl aromatic monomer / vinyl aromatic monomer / α-olefin tetrads are similar to carbon-13 NMR. It is thought to cause a peak but with slightly different chemical shifts.

These interpolymers are prepared by carrying out the polymerization in the presence of a catalyst as represented by the formula (III), optionally at a temperature of from about -30 ° C to about 250 ° C, preferably in the presence of an activating promoter:

Where

Each Cp is independently a substituted cyclopentadienyl group π-bonded to M;

E is C or Si;

M is a Group 4 metal, preferably Zr or Hf, most preferably Zr;

Each R is independently H or hydrocarbyl, silanehydrocarbyl or hydrocarbylsilyl containing up to about 30, preferably 1 to about 20, more preferably 1 to about 10 carbon or silicon atoms;

Each R ′ is independently H or halo or hydrocarbyl, hydrocarbyloxy, silane hydrocarbyl containing up to about 30, preferably 1 to about 20, more preferably 1 to about 10 carbon or silicon atoms Or hydrocarbylsilyl, or two R ′ groups can together be C _1-10 -hydrocarbyl substituted 1,3-butadiene;

m is 1 or 2.

In particular, suitable substituted cyclopentadienyl groups include those represented by Formula IV:

Where

Each R is independently H or halo or hydrocarbyl, hydrocarbyloxy, silane hydrocarbyl containing up to about 30, preferably 1 to about 20, more preferably 1 to about 10 carbon or silicon atoms, Or hydrocarbylsilyl, or two R groups together form a divalent derivative of this group. Preferably, R is each independently (including all suitable isomers) hydrogen, methyl, ethyl, propyl, butyl, pentyl, hexyl, benzyl, phenyl or silyl (where appropriate) and two such R groups bonded together to indenyl , Fluorenyl, tetrahydroindenyl, tetrahydrofluorenyl, octahydrofluorenyl, or substituted derivatives of these condensed ring systems.

Particularly preferred catalysts are, for example, racemic- (dimethylsilanediyl (2-methyl-4-phenylindenyl)) zirconium dichloride, racemic- (dimethylsilanediyl (2-methyl-4-phenylindenyl) Zirconium 1,4-diphenyl-1,3-butadiene, racemic- (dimethylsilanediyl (2-methyl-4-phenylindenyl)) zirconium di-C _1-4 alkyl, racemic- (dimethylsil Randidiyl (2-methyl-4-phenylindenyl)) zirconium di-C _1-4 alkoxide or any mixture thereof and the like.

Further methods for the preparation of the interpolymer blend component (A) of the present invention are described by Rongo and Grassie by Makromol. Chem., Volume 191, pages 2387-2396 (1990), and Danielo et al. (Journal of Applied Polymer Science, Vol. 58, pages. 1701-1706 (1995)) describe ethylene-styrene aerials. The use of catalyst systems based on methylalumoxane (MAO) and cyclopentadienyltitanium (CpTiCl ₃ ) has been reported to prepare the coalescence. Xu and Lin (Polymer Preprints, Am. Chem. Soc., Div. Polm. Chem. Volume 35, pages 686,687 (1994)) were used to obtain irregular copolymers of styrene and propylene. Copolymerization using a TiCl ₄ / NdCl ₃ / Al (iBu) ₃ catalyst was reported. Lu et al. (Journal of Applied Polymer Science, Volume 53, pages 1453-1460 (1994)) describe the copolymerization of ethylene and styrene using TiCl ₄ / NdCl ₃ / MgCl ₂ / Al (Et) ₃ catalysts. Described. The preparation of α-olefin / vinyl aromatic monomer interpolymers such as propylene / styrene and butene / styrene is described in US Pat. No. 5,244,996 to Mitsui Petrochemical Industries Ltd. All such methods disclosed for preparing the interpolymer blend components are incorporated herein by reference.

Polymers of vinylidene aromatic monomers used as component (B) in the present invention include homopolymers of a single vinylidene aromatic monomer or interpolymers prepared from one or more vinylidene aromatic monomers. Monovinylidene aromatic monomers are particularly suitable.

Monovinylidene aromatic polymers suitable for use in the component (B) and / or the expandable composition of the blends of the present invention are homopolymers or interpolymers of one or more monovinylidene aromatic monomers, or one or more monovinylidene aromatic monomers. Interpolymers of one or more monomers capable of interpolymerizing with other aliphatic α-olefins. Suitable monovinylidene aromatic monomers are represented by the following general formula (V):

Where

R ¹ is selected from the group of radicals consisting of hydrogen and hydrocarbyl radicals having up to 3 carbon atoms;

Ar is a phenyl group or a phenyl group substituted with 1 to 5 substituents selected from the group consisting of halo, C _1-4 -alkyl and C _1-4 -haloalkyl. Examples of monovinylidene aromatic monomers include styrene, para-vinyl toluene, α-methylstyrene, t-butyl styrene, chlorostyrene, and all isomers of these compounds and the like. Styrene is a particularly preferred monovinylidene aromatic monomer for the monovinylidene aromatic polymers used in the practice of the present invention.

Examples of suitable interpolymerizable comonomers other than monovinylidene aromatic monomers are C _4-6 -conjugated dienes, in particular butadiene or isoprene, N-phenyl maleimide, N-allyl maleimide, acrylamide, ethylenically unsaturated nitriles Monomers such as acrylonitrile and methacrylonitrile, ethylenically unsaturated mono- and difunctional carboxylic acids and derivatives thereof, such as esters, and anhydrides for difunctional acids such as acrylic acid, C _1-4- Alkylacrylates or methacrylates such as n-butyl acrylate and methyl methacrylate, maleic anhydride and the like or combinations thereof. In some cases, it is also desirable to copolymerize crosslinking monomers such as divinyl benzene to monovinylidene aromatic polymers.

The polymer of the monovinylidene aromatic monomer and other interpolymerizable comonomers is preferably at least 50 mol%, preferably at least 60 mol%, more preferably at least 70 mol% of at least one monovinylidene aromatic polymerized therewith. It contains a monomer.

Component B may also be a refractory rubber modified styrene blend composition. Fire resistant compositions are typically prepared by adding a flame retardant to a high impact polystyrene (HIPS) resin. The addition of flame retardants lowers the impact strength of HIPS and is restored to acceptable levels by the addition of impact modifiers, typically styrene-butadiene (SBS) block copolymers. The final composition is referred to as fire resistant polystyrene, IRPS. IRPS compositions typically contain the following ingredients:

Component R) about 50 to about 90 weight percent based on the total resin composition (R + S + T + U) of the rubber modified polymer (eg HIPS) derived from the vinyl aromatic monomer,

Component S) a halogen-containing flame retardant in an amount sufficient to provide 7-14% by weight of halogen to the composition (R + S + T + U),

Component T) about 2 to about 6 weight percent based on total resin composition (R + S + T + U) of the inorganic flame retardant synergist,

Component U) about 1 to about 8 weight percent based on total resin composition (R + S + T + U) of the impact modifier.

Component R is a rubber modified vinyl aromatic polymer. Suitable polymers typically include those made from vinyl aromatic monomers represented by the following formula (VI):

Where

R is hydrogen or methyl;

Ar is an aromatic ring structure having 1 to 3 aromatic rings with or without alkyl, halo or haloalkyl substituents, wherein any alkyl group has 1 to 6 carbon atoms and haloalkyl refers to a halogen substituted alkyl group. . Preferably, Ar is phenyl or alkylphenyl, with phenyl being most preferred. Typical vinyl aromatic monomers that can be used are all isomers of styrene, alpha-methylstyrene, vinyl toluene, especially all isomers of para-vinyl toluene, ethyl styrene, propyl styrene, vinyl biphenyl, vinyl naphthalene, vinyl anthracene, and mixtures thereof. It includes. Vinyl aromatic monomers may also be mixed with other copolymerizable monomers. Examples of such monomers include but are not limited to acrylic monomers such as acrylonitrile, methacrylonitrile, methacrylic acid, methyl methacrylate, acrylic acid and methyl acrylate, maleic anhydride, maleimide and phenylmaleimide It doesn't work.

Rubber modified vinyl aromatic polymers can be prepared by polymerizing vinyl aromatic monomers in the presence of pre-dissolved rubber to produce impact modified or grafted rubber containing products, examples of which are incorporated herein by reference in the United States. Patents 3,123,655, 3,346,520, 3,639,522 and 4,409,369. The rubber is typically butadiene or isoprene rubber, preferably polybutadiene. Preferably, the rubber modified vinyl aromatic polymer is high impact polystyrene (HIPS).

The amount of rubber modified vinyl aromatic polymer used in the composition of the present invention is typically from about 50 to about 90 weight percent, preferably from about 60 to about 88 weight percent based on the total resin composition (R + S + T + U) , More preferably about 70 to about 85 weight percent, most preferably about 72 to about 82 weight percent.

Component U is an impact modifier, which may be a polymer that increases the impact strength of the compositions of the present invention. Typical impact modifiers include copolymers of polybutadiene, polyisoprene and vinyl aromatic monomers with conjugated dienes, such as styrene-butadiene copolymers, styrene-isoprene copolymers, and include diblock copolymers and triblock copolymers . Other impact modifiers include copolymers of vinyl aromatic monomers and hydrogenated dienes, ethylene-acrylic acid copolymers and ethylene-styrene copolymers. Preferably, the impact modifier is a styrene-butadiene-styrene triblock copolymer containing about 25 to about 40 weight percent styrene component. When ethylene / styrene interpolymers are used as impact modifiers, the blend of ethylene / styrene interpolymers and polystyrene is a blend of the present invention.

The amount of impact modifier used in the compositions of the present invention is typically from about 1 to about 8% by weight, preferably from about 1 to about 7% by weight, more preferably based on the total resin composition (R + S + T + U). Is about 2 to about 6 weight percent, most preferably about 2 to about 5 weight percent.

Component S is a flame retardant which may be any halogen-containing compound or mixture of compounds that provides fire resistance to the compositions of the present invention. Suitable flame retardants are known in the art and include hexahalodiphenyl ether, octahalodiphenyl ether, decahalodiphenyl ether, decahalobiphenyl ethane, 1,2-bis (trihalophenoxy) ethane, 1, 2-bis (pentahalophenoxy) ethane, hexahalocyclododecane, tetrahalobisphenol-A, ethylene (N, N ')-bis-tetrahalophthalimide, tetrahalophthalic anhydride, hexa Halobenzenes, halogenated indane, halogenated phosphate esters, halogenated paraffins, halogenated polystyrenes and polymers of halogenated bisphenol-A with epichlorohydrin or mixtures thereof. Preferably, the flame retardant is a bromine or chlorine containing compound. In a preferred embodiment, the flame retardant is decabromodiphenyl ether or a mixture of decabromodiphenyl ether and tetrabromophenol-A.

The amount of flame retardant present in the composition of the present invention will depend on the halogen content of the particular flame retardant used. Typically, the amount of flame retardant is about 7 to about 14 weight percent, preferably about 7 to about 13 weight percent, more preferably about 8 to about 12 weight percent based on total resin composition (R + S + T + U) %, Most preferably about 9 to about 11 weight percent halogen is selected to be present in the composition of the present invention.

Component T is an inorganic flame retardant synergist known in the art as a compound which improves the effect of flame retardants, in particular halogenated flame retardants. Examples of inorganic flame retardant synergists include metal oxides such as iron oxide, tin oxide, zinc oxide, aluminum trioxide, alumina, antimony trioxide and antimony pentoxide, bismuth oxide, molybdenum trioxide and tungsten trioxide; Boron compounds such as zinc borate, antimony silicate, ferrocene and mixtures thereof, including but not limited to.

The amount of inorganic flame retardant synergist present is about 2 to about 6 weight percent, preferably about 2 to about 5 weight percent, more preferably about 2.5 to about 5 weight percent of the total resin composition (R + S + T + U). %, Most preferably about 2.5 to about 4 weight percent.

The compositions of the present invention are also suitable for small amounts of typical processing such as mold release agents, plasticizers, flow enhancers such as waxes or mineral oils, pigments, heat stabilizers, UV stabilizers, antioxidants, fillers such as glass fibers, glass beads, etc. It may contain an adjuvant.

The composition may be prepared by any blending or mixing technique that generally disperses all components uniformly through the resulting product. Examples of apparatuses include Banbury mixers, compound rolls, single screw extruders, twin screw extruders, and the like. In addition, the components of the composition may be mixed in an apparatus such as a dry blender before being fed to the mixing / melt extruder apparatus, or two or more components may be premixed and fed to the hot melt of the remaining components.

Suitable homopolymers and interpolymers that can be used in the foaming compositions of the invention include (a) at least one vinylidene aromatic monomer and / or at least one hindered aliphatic vinylidene monomer, and (b) optionally, listed in (a). Interpolymers prepared from one or more polymerizable ethylenically unsaturated monomers other than those listed above and those listed above. Suitable such polymerizable ethylenically unsaturated monomers include, for example, ethylenically unsaturated monocarboxylic acids having 3 to about 8 carbon atoms, preferably 3 to about 6 carbon atoms, more preferably 3 to about 4 carbon atoms; Anhydrides of ethylenically unsaturated dicarboxylic acids having 4 to about 10, preferably about 4 to about 8, more preferably about 4 to about 6 carbon atoms; Esters of ethylenically unsaturated monocarboxylic acids; Ethylenically unsaturated nitriles; Or combinations thereof, and the like. Particularly suitable such monomers are, for example, acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate. Latex, maleic anhydride, acrylonitrile, methacrylonitrile or combinations thereof. The interpolymer may contain from about 0 to about 50 weight percent, preferably up to about 40 weight percent, more preferably up to about 30 weight percent of a monomer different from the monomer of (a).

The blends of the present invention can be prepared by any suitable method known in the art, such as but not limited to melt blending in screw extruders, Banbury mixers, etc., after dry blending in pelletized form at the desired ratio. Dry blended pellets can be melt processed directly into the final solid product, for example by injection molding. Alternatively, the blend can be prepared, for example, by direct polymerization without the separation of the blend components using two or more catalysts in one reactor, or by the use of two or more reactors in a single catalyst and in series or in parallel.

An example of making a blend directly by polymerization is an in-reactor blend method as described in US Pat. No. 4,169,353. That is, the styrene monomer is immersed in the granules of the interpolymer blend component (A) suspended in a suitable liquid medium and graft-polymerized. The resulting blend granules are cooled and discharged from the vessel.

The foamed structure of the present invention may have any physical appearance known in the art, such as sheets, sheets or bun stock. Other useful forms are expandable or expandable particles, formable expanded particles or beads, and articles formed by expansion and / or bonding and adhesion of these particles.

The teaching of how to make and process ethylene-based polymer foam structures is edited by CP Park, edited by D. Klempner and KC Hanser Publisher, which is incorporated herein by reference. "Polyolefin Foam", Chapter 9, Handbook of Polymer Foams and Technology, Munich, Vienna, New York, Barcelona (1991).

The foamed structure of the present invention can be produced by conventional extrusion foaming methods. Structures are generally made by heating a polymeric material to form a plasticized or molten polymeric material, incorporating a blowing agent therein to form a foamable gel, and extruding the gel through a mold to form a foam product. Prior to mixing with the blowing agent, the polymeric material is heated to a glass transition temperature or above the melting point. The blowing agent may be incorporated into or mixed with the molten polymer material by means known in the art, such as extruders, mixers, blenders, and the like. The blowing agent may be mixed with the molten polymer material at an elevated temperature sufficient to prevent substantial expansion of the molten polymer material and generally to uniformly disperse the blowing agent. Optionally, the nucleating agent may be blended into the polymer melt prior to plasticization or utility, or dry blended with the polymeric material. Effervescent gels are typically cooled to low temperatures to optimize the physical properties of the foam structure. The gel is then extruded or conveyed through a mold of the desired type in a zone of reduced or low pressure to form a foam structure. The zone of low pressure is lower than that of the expandable gel prior to compression through the mold. The low pressure may be superatmospheric to low atmospheric pressure (vacuum), but is preferably at atmospheric pressure. By this method, boards, sheets, bars and tubular foamed products are produced.

The foamed structure of the present invention may be formed into stranded forms joined by extrusion of an ethylene-based polymeric material through a multi-hole mold. The holes are arranged such that contact between adjacent streams of the molten extrudate occurs during the foaming process and the contact surfaces adhere to each other with sufficient adhesion to create an integral foam structure. The stream of molten extrudate exiting the mold takes the form of strands or profiles, preferably foams and adheres to each other to form a unitary foam structure. Preferably, the individual strands or profiles joined should remain attached to the unitary structure to prevent strand delamination under the stresses that occur when producing, forming and using the foam. Apparatus and methods for making foamed structures in the form of bonded strands are shown in US Pat. Nos. 3,573,152 and 4,824,720, which are incorporated herein by reference.

The foamed structure of the present invention may also be formed by a cumulative extrusion method such as that shown in US Pat. No. 4,323,528, which is incorporated herein by reference. In this method, a low density foam structure having a large lateral cross section comprises: 1) forming a gel of the ethylene polymer material and the blowing agent under pressure at a temperature sufficient to retain the blowing agent when the viscosity of the gel expands the gel; 2) holding the gel into a retention zone maintained at a temperature and pressure that does not foam the gel, wherein the retention zone has an outlet mold that defines the aperture opening to a low pressure zone where the gel foams; the open gate closes the mold aperture. Extrude; 3) periodically open the gate; 4) Mold holes in the low pressure zone at a rate that is substantially greater than mechanical foaming by means of a movable ram on the gel, resulting in substantial foaming in the mold cavity and less than substantial irregularities in the cross-sectional area or cross section. Release it from the holding band through; 5) prepared by expanding the released gel to one or more dimensions without limitation in order to produce a foam structure.

The foamed structure of the present invention may also be formed from noncrosslinked foamed beads suitable for molding into articles. To produce foam beads, separate resin particles, such as granulated resin pellets, are suspended in a liquid medium, such as water, in which they are substantially insoluble; Being immersed in a blowing agent by introducing a blowing agent into the liquid medium at elevated pressure and at elevated temperature in an autoclave or other pressure vessel; It is quickly discharged to the area of atmospheric or reduced pressure to expand to form foam beads. Such methods are well taught in US Pat. Nos. 4,379,859 and 4,464,484, which are incorporated herein by reference.

Expandable and expanded beads can be produced by a batch or extrusion method. The batch method of making expandable beads is essentially the same as the process of making expandable polystyrene (EPS). Granules of the polymer blends produced by melt blending or in-reactor blending as described above are immersed in an aqueous suspension in a pressure vessel at elevated temperature and elevated pressure or with a blowing agent in anhydrous state. The granules are then quickly discharged into the reduced pressure area to expand to foam the beads, or cooled and discharged as unexpanded beads. The unexpanded beads are then expanded by heating with suitable means such as steam or hot air. The extrusion method is essentially the same as a conventional foam extrusion method as described above under a mold hole. The mold has multiple holes. To prepare the unfoamed beads, the foamed strands exiting the mold holes are quenched immediately in a cold water bath to prevent foaming and subsequently pelletized. Alternatively, the beads are expanded by expanding the strands by cutting them at the mold surface.

The foam beads are then molded by methods known in the art to place the foam beads into the casting, compress the casting to compress the beads, and heat the beads with a vapor, such as to bond and adhere the beads to form a product. Can be. Optionally, the beads may be dipped into air or other blowing agent at elevated pressure and at elevated temperature prior to entering the casting. The beads may also be heated before placing. Foam beads can then be molded into blocks or shaped articles by suitable molding methods known in the art. (Some methods are taught in US Pat. Nos. 3,504,068 and 3,953,558.) Excellent teachings of such methods and molding methods are described in Park, supra, p. 191.pp. 197-198, pp. 227-229.

Blowing agents useful in making the foamed structures of the present invention include inorganic blowing agents, organic blowing agents and chemical blowing agents. Suitable inorganic blowing agents include carbon dioxide, nitrogen, argon, water, air and helium. Organic blowing agents include aliphatic hydrocarbons having 1 to 6 carbon atoms, aliphatic alcohols having 1 to 3 carbon atoms, and fully or partially halogenated aliphatic hydrocarbons having 1 to 4 carbon atoms. Aliphatic hydrocarbons include methane, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane and the like. Aliphatic alcohols include methanol, ethanol, n-propanol and isopropanol. Fully or partially halogenated aliphatic hydrocarbons include fluorocarbons, chlorocarbons and chlorofluorocarbons. Examples of fluorocarbons are methyl fluoride, perfluoromethane, ethyl fluoride, 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-143a), 1,1 , 1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), pentafluoroethane, difluoromethane, perfluoroethane, 2, 2-difluoropropane, 1,1,1-trifluoropropane, perfluoropropane, dichloropropane, difluoropropane, perfluorobutane, perfluorobutane. Partially halogenated chlorocarbons and chlorofluorocarbons for use in the present invention include methyl chloride, methylene chloride, ethyl chloride, 1,1,1-trichloroethane, 1,1-dichloro-1-fluoroethane (HCFC -141b), 1-chloro-1,1-difluoroethane (HCFC-142b), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123) and 1-chloro-1, 2,2,2-tetrafluoroethane (HCFC-124). Fully halogenated chlorofluorocarbons include trichloromonofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), trichlorotrifluoroethane (CFC-113), 1,1,1-tri Fluoroethane, pentafluoroethane, dichlorotetrafluoroethane (CFC-114), chloroheptafluoropropane and dichlorohexafluoropropane. Chemical blowing agents include sodium bicarbonate, mixtures of sodium bicarbonate and citric acid, azodicarbonamide, azodiisobutyronitrile, benzenesulfonhydrazide, 4,4-oxybenzene sulfonyl-semicarbazide, p-toluene sulfonyl Semi-carbazide, barium azodicarboxylate, N, N'-dimethyl-N, N'-dinitrosoterephthalamide and trihydrazino triazine. Preferred blowing agents depend on the method and the product. In order to produce low density foams by the extrusion method, volatile organic blowing agents or carbon dioxide are preferred. Preferred volatile organic blowing agents include n-butane, isobutane, n-pentane, isopentane, HFC-152a and mixtures thereof. In order to produce expandable bead products, isobutane, n-pentane, isopentane and mixtures thereof are preferred.

The amount of blowing agent incorporated into the polymer melt material to prepare the foam-forming polymer gel is from about 0.05 to about 5.0 g moles, preferably from about 0.2 to about 0.4 g moles, most preferably from about 0.5 to 3.0 g moles per kg polymer. to be.

Numerous additives such as nucleating agents, inorganic fillers, pigments, antioxidants, acid removers, ultraviolet absorbers, flame retardants, processing aids, extrusion aids and the like can be incorporated into the foam structures of the present invention.

In addition, nucleating agents may be added to control the size of the foaming cells. Preferred nucleating agents include inorganic materials such as calcium carbonate, talc, clay, titanium oxide, silica, barium sulfate, diatomaceous earth and a mixture of citric acid and sodium bicarbonate. The amount of nucleating agent used may be about 0.01 to about 5 parts by weight per 100 parts by weight of the polymer resin.

The foamed structure of the present invention is substantially noncrosslinked or noncrosslinked. Alkenyl aromatic polymer materials, including foam structures, are substantially free of crosslinks. The foamed structure contains about 5% gel in accordance with ASTM D-2765-84 Method A. Some naturally occurring crosslinks can be tolerated without the use of crosslinkers or spinning.

The foamed structure of the present invention has a density of less than 450 kg / m ³ , more preferably 200 kg / m ³ , most preferably about 10 to about 80 kg / m ³ . The foam has an average cell size of about 0.02 to about 5.0 mm, more preferably about 0.2 to about 2.0 mm, most preferably 0.3 to about 1.8 mm according to ASTM D3576.

The foamed structure of the present invention may have any physical appearance known in the art, such as compressed sheets, rods, plates and profiles. The foam structure may also be formed by molding the expandable beads to any of the stated or any other shapes.

The foam structure of the present invention may be closed cell type or open cell type. Preferably, the foam of the present invention contains at least 80% closed cells according to ASTM D2856-A.

In addition, antioxidants (e.g. hindered phenols such as Iganox 1010 (IRGANOX)), phosphites (e.g. Igafos 168 (IRGAFOS)), UV stabilizers, adhesive additives Additives such as polyisobutylene, antiblock additives, colorants, pigments, fillers and the like can be included in the interpolymers used in the blends of the present invention to the extent that they do not interfere with the improved properties found by the applicant. .

The additives are used in functionally equivalent amounts known to those skilled in the art. For example, the amount of antioxidant used is that amount which prevents the polymer or polymer blend from oxidizing at the temperature and environment used during storage and ultimate use of the polymer. Such amount of antioxidant is from about 0.01 to about 10 weight percent, preferably from about 0.05 to about 5 weight percent, more preferably from about 0.1 to about 2 weight percent, based on the weight of the polymer or polymer blend.

Similarly, the amount of any other listed additive acts like an amount that renders the polymer or polymer blend antiblocking, loads the desired amount of filler to produce the desired result, and provides the desired color from the colorant or pigment. The same amount as the enemy. Such additives may suitably be used in about 0.05 to about 50 weight percent, preferably about 0.1 to about 35 weight percent, about 0.2 to about 20 weight percent, based on the weight of the polymer or polymer blend. However, in the case of fillers, they may be used at up to about 90% by weight, based on the weight of the polymer or polymer blend.

The blends of the present invention can be used to produce a wide range of products such as, for example, calendered sheets, blown films, injection molded parts and the like. Blends can also be used in the manufacture of fibers, foams and latexes. Blends of the invention can also be used in adhesive formulations.

The compositions of the present invention containing fire resistant polystyrene modified with ethylene / styrene interpolymers can be used in injection molding applications for making TV cabinets, computer monitors, printer equipment, and the like.

The following examples are illustrative of the invention but are not intended to limit the scope thereof in any way.

exam

The properties of the polymers and blends were determined by the following test procedure.

Melt flow rate (MFR) was measured by ASTM D-1238 (1979) Condition E (190 ° C .; 2.16 kg).

ASTM D-882- except that the tensile strength was repeated 5 times for each polymer blend tested and the grip separation was always 1 inch (2.54 cm) and the grip separation rate was always 5 mm / min. 91, measured by process A.

ASTM D-882-91 except that the modulus was repeated 5 times for each polymer blend tested and grip separation was always 1 inch (2.54 cm) and grip separation speed was always 5 mm / min. , Measured by process A.

ASTM D-882-91, except that elongation was repeated five times for each polymer blend tested and grip separation was always 1 inch (2.54 cm) and grip separation rate was always 5 mm / min. , Measured by process A.

ASTM D-882-91, except that the test was repeated five times for each polymer blend tested for toughness and the grip separation was always 1 inch (2.54 cm) and the grip separation rate was always 5 mm / min. , Measured by process A2.1.

Preparation of Ethylene / Styrene Interpolymers A to G

About 500 ml of mixed alkane solvent (ISOPA®, commercially available from Exxon Chemicals Inc.) and about 500 ml of styrene comonomer in a 2 liter stirred reactor Put it. Hydrogen was then added by differential pressure expansion from a 75 ml shot tank. The reactor was heated to the desired run temperature and the reactor saturated with ethylene at the desired pressure. (Tetramethylcyclopentadienyl) (tert-butylamido) di-methylsilane titanium dimethyl catalyst and tris (pentafluorophenyl) borane cocatalyst were mixed in isopa E® in an inert atmosphere glove box. The catalyst and cocatalyst were mixed by mixing in a dry box. The resulting solution was transferred to a catalyst addition tank and injected into the reactor. The polymerization was carried out as necessary with ethylene. It was optionally added during the subsequent addition of the catalyst solution prepared by the same technique. After the run time, the polymer solution was removed from the reactor and mixed with 100 mg of Iganox 1010® in 10 ml of toluene. The polymer was precipitated with propanol and the volatiles were removed from the polymer in a reduced pressure vacuum oven at 120 ° C. for about 20 hours.

The amount of monomers and polymerization conditions are provided in Table 1A. Yields and polymer properties are provided in Table 1B.

Example 1

A. Ethylene / Styrene Interpolymers

The ethylene / styrene interpolymers designated H in Tables 1A and 1B above were used in this example.

B. Preparation of E / S Interpolymers and Polystyrene Blends

The polymeric material was pelletized and mixed with general purpose polystyrene (PS) having a weight average molecular weight of about 200,000 and a polydispersity of 2.5. The content of E / S copolymer in this blend varied from 0 to 40%. The test is as follows. A total of 40 g of granule resin blend was melt blended at 30 rpm rotator speed under a blanket of nitrogen at 180 ° C. for 15 minutes using a Haake Rheocord Model 90 mixer. The blend was pressed to a thin sheet about 0.9 mm thick in a hot press maintained at 177 ° C. The sheet was cut into strips having a width of 1/2 inch (1.27 cm) using a Twin-Albert Model LDC-50 cutter. The tensile properties of this sample were measured at a crosshead speed of 5 mm / min and a jaw span of 1 inch (2.54 cm) with an Instron 1123 toughness tester. Five samples were taken for each blend and reacted and the average of the five data values reported as representative properties of each blend.

The test results are shown in Table 2. At an E / S content of less than 40%, the blend did not significantly improve mechanical strength. At a blend content of 40%, this property of the blend was greatly improved. 60/40 PS / ES blends can extend beyond 70% of their original length and have a relatively high modulus. Transmission electron micrographs showed that the blend had a co-continuous structure.

Example 2

In this example, the test of Example 1 was repeated with six different ES interpolymers having various ethylene / styrene ratios and melt indexes. ES interpolymers were prepared by applying different ethylene / styrene ratios as shown in Table 1A. All materials contained small amounts (less than 5.2%) of amorphous polystyrene. 40 parts by weight of each ES interpolymer were blended into 60 parts by weight of polystyrene as used in Example 1. As shown in Table 3, all ES interpolymer materials produced tough polyblends. In general, the ES interpolymer with more styrene showed better performance. The ES interpolymers used in test number 2.5 showed exceptional performance. The performance of this resin was much lower than the general tendency. It is believed that the relatively poor performance of this material is due to its high melt index (or low viscosity).

Example 3

In this example, test number 2.6 was repeated by replacing the polystyrene component with another polystyrene having a weight average molecular weight of 300,000 and a polydispersity of 2.4. As shown in Table 4, this resin blend has desirable toughness and relatively high modulus.

Example 4

In this example, an ES interpolymer (interpolymer A disclosed in Tables 1A and 1B) having 20.1 mol% (48.3% by weight) of styrene was mixed with the polystyrene resin in 10% and 20% content as used in Example 1 Mixed. The ES interpolymer contains about 4% amorphous polystyrene in the total polymer. As shown in Table 5, the ES interpolymer content of 20% or less in the blend was insufficient to achieve a tough blend.

Comparative Example A (Not an Example of the Invention)

In this comparative example, the polystyrene of Example 1 was commercially available from styrene-butadiene-styrene tri-block interpolymer (SBS) (Vector 6241-D, commercially available from Decoco Polymers). (VECTOR) .PS / SBS blends of 60/40 have good elongation and desirable toughness, as shown in Table 6. However, these blends exhibit low modulus values as compared to PS / ES blends. Low strength, as is high Modulus is preferred in most cases where polymer blends are used.

Example 5

Preparation of ES Copolymer

Substantially irregular ethylene / styrene (ES) copolymers, designated H in Tables 1A and 1B, were used in this example. This ES copolymer contains 76.9 wt% (47.3 mol%) of styrene moieties and has a melt index of 0.92 as measured by ASTM D-1238 at 190 ° C./2.16 kg.

Expansive test

In this example, the blend prepared in Example 1 was used. This blend was compression molded in a mold having a diameter of about 1 inch (25.4 mm) and a depth of 0.1 inch (2.5 mm) in a hot press maintained at about 180 ° C.

Three disc-shaped samples per formulation were mounted on a wire graduate carriage connected to a Teflon® fluoropolymer in a press. The carriage was bonded to the support, which was then placed so as not to come into direct contact with the liquid blowing agent present at the bottom of the reactor. About 2.8 g of isopentane was placed in the reactor. After the lid was closed and nitrogen was blown to remove oxygen, the reactor was heated in an oil bath maintained at 60 ° C. for about 6 days. The reactor was cooled down and the sample removed. The thickness of the sample after immersion in the blowing agent was 70 mils (1.8 mm) to 127 mils (3.2 mm). Soon, one sample for each formulation was cut in half and the fragments were exposed to steam for 5 minutes. As shown in Table 7, the PS / ES blends absorbed and expanded isopentane in excess of 10 parts by weight (pph) per 100 parts by weight of the polymer, resulting in low density. The 90/10 PS / ES blend had the lowest density of 44 kg / m 3.

In contrast, pure polystyrene samples absorb and expand isopentane at less than 3 pph, resulting in a density of 94 kg / m 3. The relatively high density foams of the PS / ES blend of 60/40 are thought to be due to excessive long exposure to steam. The blend foam showed shrinkage when taken out of the vaporizer.

Blowing agent

The blowing agent retention of the sample immersed in isopentane was examined by periodically measuring the weight of the sample during aging at room temperature of 23 ° C. The observations continued for eight months and the data are summarized in Table 10. Since the fractional loss of the blowing agent is inversely proportional to the square of the thickness, it is necessary to compare the data in terms of the corrected aging time (corrected with a 2 mm thick sample). For ease of comparison, data were interpolated to show blowing agent retention at separate aging times as shown in Table 8. The data indicate that the PS / ES blend retains isopentane better than pure polystyrene. The PS / ES blend retained at least 65% of the initial blowing agent for three months, but the polystyrene sample lost half of the blowing agent within one week.

The ethylene-styrene copolymer prepared above was compression molded into disks in the same manner as described above. Disk samples were immersed in HCFC-141b at 60 ° C. for 8 days in each of these procedures. Blowing agent retention of the samples was observed by weighing periodically during aging for 6 days at room temperature of 23 ° C. The thickness of the sample was about 3 mm. As shown in Table 9, the sample had a good retention of HCFC-141b blowing agent.

Examples 6-13

The preparation and properties of the interpolymers are as follows.

Preparation of Interpolymers J, K, and L

The polymer was prepared in a 400 gallon shaken semi-continuous batch reactor. The reaction blend consisted of a mixture of cyclohexane (85% by weight) and isopentane (15% by weight), and about 250 gallons of solvent comprising styrene. Prior to addition, the solvent, styrene and ethylene were purified to remove oxygen and moisture. Inhibitors present in styrene were also removed. Inert material was removed by filling the reactor with ethylene. The pressure in the reactor was then adjusted to the set point using ethylene. Hydrogen was added to adjust the molecular weight. The temperature of the reactor was adjusted to the set point by varying the water temperature of the reactor jacket. Prior to polymerization, the reactor is heated to the desired reaction temperature and the catalyst component vs. titanium vs. (N-1,1-dimethylethyl) dimethyl (1- (1,2,3,4,5-eta) -2,3, 4,5, -tetramethyl-2,4-cyclopentadien-1-yl) silaneaminato)) (2-) N) -dimethyl (CAS # 135072-62-7), tri (pentafluorophenyl) Mix and mix the boron (CAS # 001109-15-5) and modified methylalumine-oxane type 3A (CAS # 146905-79-5) ratios so that the molar ratio is 1/3/5 respectively, Added. After the polymerization reaction began, ethylene was optionally fed to the reactor to maintain pressure in the reactor. In some cases, hydrogen was added to the headspace of the reactor to maintain the molar ratio relative to the ethylene concentration. At the end of the reaction, the flow of catalyst was stopped and ethylene was removed from the reactor, then about 1000 ppm of Irganox 1010® antioxidant was added to the solution and the polymer was separated from the solution. The catalyst efficiency was generally greater than the efficiency of forming 100,000 pounds of polymer per pound of Ti. The resulting polymer was separated from the solution by stripping with steam in the reactor or using a devolatilization extruder. In the case of stripping the material with steam, a method of further reducing the residual moisture and any unreacted styrene in an apparatus such as an extruder was further used.

The properties of the interpolymers and vinyl aromatic polymers are described in Table 10. Unmixed polymers were provided as comparative examples.

The test portion and the characteristic data of the interpolymer and the blend of interpolymers were carried out according to the following procedure.

Compression Molding: Samples were melted at 190 ° C. for 3 minutes and compression molded at 190 ° C. again for 2 minutes at a pressure of 20,000 pounds. The molten material was then quenched in a press down to room temperature.

Density: The density of the samples was measured by ASTM-D792.

Differential scanning calorimetry (DSC): The thermal transition temperature and the calorific value of the interpolymer were measured using Dupont DSC-2920. In order to remove the pre-existing heat, the sample was first heated to 200 ° C. Heating and cooling curves were recorded at a rate of 10 ° C./min. Melting (by secondary heating) and crystallization temperatures were recorded from the temperature peaks of the endothermic and exothermic curves, respectively.

Melt Shear Rheology: Vibratory shear rheology was measured with a Rheometrics RMS-800 rheometer. Rheological properties were observed at a constant set temperature of 190 ° C. in a frequency sweep mode. In the tabulated data, η is the viscosity and η (100 / 0.1) is the viscosity ratio of the numerical value recorded at 100 / 0.1 rad / sec.

Mechanical Test: Shore A hardness was measured at 23 ° C. according to ASTM-D240. Flexible modulus was measured according to ASTM-D790. Tensile properties of the compression molded samples were measured using an Instron 1145 tension meter equipped with an extensiometer. ASTM-D638 samples were tested at an elongation rate of 5 min ⁻¹ . Four tensile measurements were averaged. Yield stress and yield strain were recorded at the inflection point of the stress / strain curve. The energy at break is the area under the stress / strain curve.

Relaxation of Tensile Stress: Relaxation of uniaxial tensile stress was measured with an Instron 1145 tensile meter. The compression molded film (thickness of ˜20 mils (0.058 cm)) having a gauge length of 1 inch (2.54 cm) was deformed to have a strain of 50% at a strain rate of 20 min ⁻¹ . The force required to maintain 50% strain was observed for 10 minutes. The magnitude of the stress relaxation is defined as (f _i -f _f / f _i ), where f _i is the initial force and f _f is the final force.

Thermomechanical Analysis (TMA): Data were obtained with a Perkin Elmer TMA Series 7 device. Using a heating rate of 5 ° C./min and a load of 1 Newton, probe permeability was measured at a depth of 1 mm for a 2 mm thick compression molded portion.

Examples 6-8

Blend Preparation: Three blend compositions (Examples 6, 7 and 8) were prepared using a Hake mixer equipped with a Rheomix 3000 bowl of the interpolymer (J) / vinyl aromatic polymer (D). The weight ratios were prepared at 90/10, 70/30 and 50/50. The blend ingredients were first dry mixed and then poured into a mixer at a temperature equilibrated to 190 ° C. Injection and temperature equilibration took about 3 to 5 minutes. The molten material was mixed at 190 ° C. at 40 rpm for 10 minutes.

The characterization data of these blends and their blend components is shown in Table 11.

In general, olefinic polymers have poor compatibility with vinyl aromatic polymers and there is a need to provide some form of compatibility technique to achieve good performance characteristics. This poor compatibility is generally associated with low toughness.

However, Table 11 shows that all blend compositions of Examples 6, 7, and 8 had good mechanical integrity and did not lose strength performance as shown in stress, strain and energy at break. The 50/50 composition showed lower toughness compared to the other two compositions, but showed ten times greater toughness than the unmodified vinyl aromatic polymer.

In addition, these blends have a surprising degree of stress relaxation compared to what would be expected of a component polymer. As shown in thermomechanical analysis (TMA) tests using probes penetrated to a depth of 1 mm, the high temperature performance of the compositions is greatly improved in these blends. Example 8, comprising 50% by weight of polystyrene, exhibits similar permeation resistance as polystyrene.

The melt rheological data of the three blend examples 6, 7 and 8 show that low shear performance (0.1 rad / sec) can be manipulated by blending with blends with low viscosity. At low shear rates of Examples 7 and 8, a low value of tangent δ appeared. This fact indicates that, compared to unmodified interpolymers, it has higher melt elasticity and improved parts that characterize under certain melt processing operations.

Examples 9-11

Blend Preparation: Three blend compositions (Examples 9, 10 and 11) were used with a Hake mixer equipped with a Leomix 3000 bowl to obtain a weight ratio of the interpolymer (K) / vinyl aromatic polymer (D) of 85/15, Prepared at 70/30 and 50/50. The blend ingredients were first dry mixed and then poured into a mixer at a temperature equilibrated to 190 ° C. Injection and temperature equilibration took about 3 to 5 minutes. The molten material was mixed at 190 ° C. at 40 rpm for 10 minutes.

The properties of these three blends and these blend components are shown in Table 12.

Table 12 shows that all blend compositions of Examples 9, 10 and 11 had good mechanical integrity and did not lose strength performance as shown in stress, strain and energy at break relative to each component polymer. The 50/50 composition showed lower toughness than the other two compositions, but showed higher toughness than the unmodified vinyl aromatic polymer.

In addition, blends 9 and 10 exhibit a high degree of stress relaxation compared to the component interpolymers.

The melt rheological data of the three blend examples 9, 10 and 11 show that low shear performance (0.1 rad / sec) can be manipulated by blending with blends with low viscosity.

Example 12 and Example 13

Blend Preparation: Two blend compositions (Examples 12 and 13) were used with a Hake mixer equipped with a Leomix 3000 bowl to reduce the weight ratio of the interpolymer (L) / vinyl aromatic polymer (D) to 75/25 and 50 /. It prepared by 50. The blend ingredients were first dry mixed and then poured into a mixer at a temperature equilibrated to 190 ° C. Injection and temperature equilibration took about 3 to 5 minutes. The molten material was mixed at 190 ° C. at 40 rpm for 10 minutes.

The properties of these blends and these blend components are shown in Table 13.

Examples 12 and 13 show excellent compatibility in olefin-rich interpolymers, as shown in the mechanical properties data. The blend shows high yield stress and good strain at break. In addition, Blend 12 exhibits a surprising degree of stress relaxation compared to interpolymer (L).

These blends exhibit low tangent δ values, which indicates that they have higher melt elasticity and improved properties that characterize under certain melt processing operations, compared to other blend compositions.

Example 14

A. Preparation of Ethylene / Styrene Copolymers:

The ethylene / styrene copolymer was then subjected to (tert-butyl-amido) dimethyl (tetramethyl-ta5-cyclopentadienyl) silane dimethyltitanium (IV) catalyst and tri (pentafluorophenyl) borane promoter It was prepared according to the procedure. In a 2-liter stirred reactor was charged about 360 g of mixed alkane solvent (commercially available as isopa E®) and about 460 g of styrene comonomer. Hydrogen was added to the reactor by differential pressure expansion from a 75 ml addition tank. The reactor was heated to 80 ° C. and the reactor saturated with ethylene at the desired pressure. The desired amount of 0.005 M solution of the promoter in toluene was added to the solution of the catalyst in toluene in a dry box by pipetting to mix the catalyst and promoter. The resulting solution was transferred to a catalyst addition tank and injected into the reactor. Ethylene was added as needed during the polymerization reaction. Additional amounts of catalyst and cocatalyst were periodically added to the reactor. After 20 minutes, the polymer solution was removed from the reactor and quenched with isopropyl alcohol. 100 mg of hindered phenolic antioxidant (Arganox 1010®, available from Ciba Geigy Corp.) was added to the polymer. The volatiles were removed from the polymer for about 20 hours in a reduced pressure vacuum oven at 135 ° C. Ethylene and delta H ₂ pressures were used to prepare the ethylene / styrene copolymer, and the melt index (I ₂ ) and styrene content of the resulting copolymers are shown in Table 14 below.

B. Preparation of Injection Molded Samples for Testing:

The components of Table 15 were compounded on a Baker Perkins MPC with a 30 mm twin screw V30 mixer at 190 ° C. to 210 ° C. followed by a 38 mm single screw extruder with air pores. The molten polymer was passed through a mold with two holes and the polymer strand was cooled in a water bath and cut into pellets.

Resin was injection molded on a Demag D100-75 injection molding machine equipped with a barrel of 31 mm diameter and a mold with space to place the sample was used for the property test.

The test results of the molded fire resistant polystyrene (IRPS) blends are shown in Table 16 below.

The total energy absorbed in the Gardner impact test was 73-157 in-lbs (84-181 kg-cm) for the SBS copolymer compared to 90 in-lbs (104 kg-cm). Numerical values in this range can improve (1) the impact strength of fire resistant HIPS by adding ES interpolymers, and (2) the impact strength of fire resistant polystyrene (IRPS) is affected by the composition of the E / S copolymer. And (3) indicate that the impact strength of the IRPS comprising the interpolymer is comparable to or greater than the impact strength of the IRPS comprising typical SBS (currently commercially available impact modifiers).

Claims (16)

(A) (1) (a) at least one vinylidene aromatic monomer, or (b) at least one hindered aliphatic vinylidene monomer, or (c) at least one vinylidene aromatic monomer and at least one hindered aliphatic vinylidene monomer. A combination of about 1 to about 65 mole percent, and (2) about 1 to about 99 weight percent of at least one interpolymer containing about 35 to about 99 mole percent of at least one aliphatic α-olefin having 2 to about 20 carbon atoms ; And (B) one or more homopolymers of (1) vinylidene aromatic monomers, or (2) one or more interpolymers of one or more vinylidene aromatic monomers and / or one or more hindered aliphatic vinylidene monomers, or (3) From about 1 to about 99 weight percent of one or more of (1) and (2), or (4) a combination of two or more of (1), (2) and (3), further containing an impact modifier Blend of polymeric material, including. The method of claim 1, Component (A) is used at about 35 to about 99 weight percent based on the total amount of components (A) and (B); Blend wherein component (B) is used at from about 1 to about 65 weight percent based on the total amount of components (A) and (B). The method of claim 1, Component (A) is used at about 40 to about 97 weight percent based on the total amount of components (A) and (B); Blend wherein component (B) is used at about 3 to about 60 weight percent based on the total amount of components (A) and (B). The method of claim 1, Component (A) is used at about 40 to about 95 weight percent based on the total amount of components (A) and (B); Blend wherein component (B) is used at about 5 to about 60 weight percent based on the total amount of components (A) and (B). The method according to any one of claims 1 to 4, (i) the carbon number of component (A2) is 2 to 12; (ii) Blends in which the monovinylidene aromatic monomer (s) of component (B) are represented by formula (V): Formula V Where R ¹ is selected from the group consisting of hydrogen and alkyl radicals of up to 3 carbon atoms, Ar is a phenyl group or a phenyl group substituted with 1 to 5 substituents selected from the group consisting of halo, C _1-4 -alkyl and C _1-4 -haloalkyl. The method according to any one of claims 1 to 5, The interpolymerizable monomer of component (B) is α-methyl styrene, N-phenyl maleimide, N-alkyl maleimide, acrylamide, acrylonitrile, methacrylonitrile, maleic anhydride, acrylic acid, C _1-4- Blend selected from the group consisting of alkyl acrylates or C _1-4 -alkyl methacrylates. The method according to any one of claims 1 to 6, Blend wherein component (B) is polystyrene or polystyrene containing an impact modifier. The method according to any one of claims 1 to 7, Component (A1a) is styrene; Blend wherein component (A2) is ethylene or a combination of ethylene with at least one of propylene, 4-methyl pentene, butene-1, hexene-1 and octene-1. The method according to any one of claims 1 to 8, Component (A1a) is styrene; Component (A2) is ethylene or a combination of ethylene and at least one of propylene, 4-methyl pentene, butene-1, hexene-1 and octene-1; Blend wherein component (B) is polystyrene or polystyrene containing an impact modifier. The method according to any one of claims 1 to 9, Blend wherein component (A) is produced by polymerization in the presence of a metallocene or a catalyst and cocatalyst of defined structure. Adhesive composition containing the blend according to any one of claims 1 to 10. A sheet or film formed by calendering, casting, or blowing a blend according to any one of claims 1 to 10. A product formed by injection, compression, extrusion or blow molding the blend according to any one of claims 1 to 10. Fibers, foams or latexes made from the blend according to any one of claims 1 to 10. (I) at least one blowing agent; And (II) (A) (1) (a) at least one vinylidene aromatic monomer, or (b) at least one hindered aliphatic vinylidene monomer, or (c) at least one vinylidene aromatic monomer and at least one hindered aliphatic About 1 to about 65 mole% of a combination of vinylidene monomer, and (2) about 1 to about 100 mole of at least one interpolymer comprising about 35 to about 99 mole% of at least one aliphatic α-olefin having 2 to about 20 carbon atoms. weight%; And (B) homopolymers of vinylidene aromatic monomers and / or hindered aliphatic vinylidene monomers, or one or more vinylidene aromatic monomers and / or one or more hindered aliphatic vinylidene monomers and optionally said vinylidene aromatic monomers or hindered aliphatic At least one interpolymer or interpolymer blend comprising 0 to about 99 weight percent of at least one interpolymer of at least one polymerizable ethylenically unsaturated monomer that is not a vinylidene monomer Foamable composition comprising a. A foam formed by applying the foamable composition according to claim 15 to foaming conditions.