JP3400103B2 - Thermoplastic resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition comprising a mixture of a polycarbonate polymer and a specific block copolymer having a terminal hydroxyl group. [0002] polycarbonate over preparative polymer transparency, impact resistance, heat resistance, electrical has dimensional stability superior characteristics, electrons, are used in wide range of fields such as automobiles I have.
However, this excellent impact resistance is also significantly reduced in the low temperature range. For the purpose of improving the low-temperature impact resistance, styrene-
An elastomer such as a hydrogenated conjugated diene copolymer may be added. However, the method of adding this elastomer has problems that the effect of improving the impact resistance at low temperatures is insufficient, the compatibility is not sufficient, and delamination occurs in the molded article. An object of the present invention is to provide a thermoplastic resin composition comprising a polycarbonate polymer having improved impact resistance at low temperatures without delamination. . [0004] According to the present invention, the above object is achieved by a composition comprising a polycarbonate resin mixed with a block copolymer having a hydroxyl group at a terminal. More specifically, (a) 95 to 30 parts by weight of a polycarbonate resin, (b) a polymer block mainly composed of an aromatic vinyl compound and polybutadiene having a 1,2-bond content of 20% or less are hydrogenated. At least one block A selected from the group consisting of hydrogenated polybutadiene blocks obtained by the above method, hydrogenated polyisoprene blocks, and water obtained by hydrogenating polybutadiene having a 1,2-bond content of 30 to 70%. A modified block copolymer having a hydroxyl group at a terminal of a block copolymer containing a polybutadiene block and at least one block B selected from the group consisting of a hydrogenated isoprene and a random copolymer block of butadiene (b) −
1 ) Achieved by a thermoplastic resin composition containing 5 to 70 parts by weight. Hereinafter, the present invention will be described in detail. The polycarbonate resin used as the component (a) in the thermoplastic resin composition of the present invention is a polymer having a carbonate structure in the main chain, and has a structure of bisphenol A carbonate. The modified block copolymer (b-1) having a hydroxyl group at a terminal, which is the component (b) used in the thermoplastic resin composition of the present invention, is obtained by an anionic polymerization method. be able to. The modified block copolymer having a hydroxyl group at a terminal obtained by the anionic polymerization method includes aromatic aromatic compounds such as styrene, α-methylstyrene, 3-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene and 2-vinylnaphthalene. block obtained by polymerizing a family vinyl compound of at least one block or one butadiene monomer, 2-bond content was exposed, selected from among a polybutadiene block polymerization was carried out such that the 2 0% or less, (Block A)
And a polyisoprene block, or a polyvinylisoprene block obtained by polymerizing isoprene monomer so that 1,2 bonds or 3,4 bonds become 30% to 60%, or a random copolymerized block of isoprene and butadiene, or The butadiene monomer has a 1,2 - bond content of 30%
Adding hydroxyl-terminated block copolymer having at least one block (Block B) selected ~ 70% become so the polymerization from the port re butadiene block was performed, block comprising a conjugated diene It is obtained by hydrogenating the double bonds in it. [0010] modified block copolymer having a hydroxyl group to such end (b-1) is the block A and the block B
Are (AB) p-OH, (BA) q-OH, A (B
A) r-OH, and B (AB) s-OH (where p,
q, r, and s each represent an integer of 1 or more, and OH represents a hydroxyl group).
p, q, r and s can be arbitrarily determined, but are usually selected from a range of 5 or less. The modified block copolymer (b-1) having a hydroxyl group at the terminal may be used in a state where a modified block copolymer having a hydroxyl group at the terminal of two or more types of structures is mixed in some cases. There is no problem. The modified block copolymer (b-1) having a hydroxyl group at the terminal is obtained by a conventional method such as anion living polymerization using an organic alkali metal catalyst, and after adding a hydroxyl group to the terminal, this is added to water. Obtained by adding. For example, (AB) p-OH, or A
(BA) To polymerize r-OH, a saturated aliphatic hydrocarbon compound such as hexane, heptane, cyclohexane or the like, or benzene, toluene or the like is used by using an anionic polymerization initiator such as n-butyllithium or s-butyllithium. A living polymer is produced by anionic polymerization of an aromatic vinyl compound monomer or a butadiene monomer at a temperature of 30 to 60 ° C. using an aromatic hydrocarbon compound as a solvent, followed by isoprene monomer Is dropped into the system and
Obtain the original block copolymer. Further aromatic vinyl reactivated
If a compound monomer or a butadiene monomer is dropped into the system, a ternary block copolymer can be produced. By repeating this operation, a quaternary or higher block copolymer is obtained. On the other hand, to polymerize (BA) q-OH or B (AB) s-OH, a living polymer is produced by anionic polymerization of an isoprene monomer, followed by aromatic vinylation .
The compound monomer or butadiene is dropped into the system to obtain a binary block copolymer. Furthermore it is possible to produce a ternary block copolymer if again dropwise a conjugated diene emissions monomer in the system. This operation is repeated to obtain a quaternary or higher block copolymer. The 1,2-bond amount of 30% to 70% Po Li <br/> butadiene block in addition an appropriate amount to the system dioxane or tetrahydrofuran, can be obtained by dropwise addition of butadiene monomer. Similarly, a polyvinyl isoprene block can be obtained by adding an appropriate amount of dioxane or tetrahydrofuran to the system and then dropwise adding an isoprene monomer. When ethylene oxide or propylene oxide is added when the block copolymer reaches a desired molecular structure and molecular weight, the polymerization is terminated by adding alcohols, carboxylic acids, water, and the like. Subsequently, the resulting copolymer is hydrogenated to obtain a modified block copolymer having a hydroxyl group at the terminal (b-
1) is manufactured. As the hydrogenation catalyst, a homogeneous catalyst or a heterogeneous catalyst can be used. When a homogeneous catalyst is used, an organic transition metal catalyst (for example, nickel acetylacetonate, cobalt acetylacetonate, nickel naphthenate, cobalt naphthenate, etc.) and aluminum,
Isoprene monomer contained in a polymer subjected to hydrogenation with a Ziegler catalyst or the like in combination with an alkylated metal such as an alkali metal and an alkaline earth metal;
Is 0.01 to per double bond based on butadiene monomer.
Use about 0.1 mol%. Hydrogenation reaction is normal temperature to 150
C., under a hydrogen pressure of normal pressure to 50 kg / cm ² ,
It ends in ~ 50 hours. After the reaction is completed, acidic water is added to the vessel, and the mixture is vigorously stirred to dissolve the hydrogenation catalyst in water. Phase separation two phases the aqueous phase of the removal is, by further distilling off the solvent, varying with terminal hydroxyl groups of interest
To obtain a functional block copolymer (b-1) . In the modified block copolymer (b-1) having a terminal hydroxyl group used in the present invention, 50% or more of the carbon-carbon double bonds in the block comprising the conjugated diene monomer are hydrogenated. The degree of hydrogenation is desirably 80% or more from the viewpoints of heat deterioration resistance, weather resistance, and the like. The hydroxyl group of the modified block copolymer (b-1) having a hydroxyl group at the terminal is the terminal of the block A and the block
Although it may be added to any of the B-terminals , one added to the end of block A which is a hard block is preferable, and one added to the end of the styrene block is most preferably used. The number average molecular weight of the block A of the block copolymer having a hydroxyl group at the terminal is 5,000 to 5,000.
It is preferably in the range of 0. The number average molecular weight of the block B is preferably in the range of 10,000 to 100,000. Further, the number average molecular weight of the entire modified block copolymer (b-1) is in the range of 15,000 to 150,000. The weight ratio between block A and block B is
Although there is no particular limitation, those in the range of 1: 9 to 7: 3 are preferably used. Further, the concentration of hydroxyl group of the terminal is required to be 0.5 or more per molecule. The concentration of hydroxyl groups is high keep it difficult mechanical properties of the compositions of the present invention is smaller than the above range. The concentration of hydroxyl groups from such a viewpoint is more preferably a modified block copolymer 1 0.75 or <br/> more per molecule. In the thermoplastic resin composition of the present invention, the ratio of the polycarbonate resin to the modified block copolymer having a hydroxyl group at a terminal is from 95/5 to 30/7 by weight.
Must be in the range of 0. Less place than the proportion of the modified block copolymer is 5 wt% terminated with a hydroxyl group
In such a case, the effect of improving the impact resistance of the finally obtained resin composition is undesirably reduced. The decrease in the elastic modulus of the thermoplastic resin composition obtained when exceeding the above range, such as reduction of mechanical strength is too large is not preferable. From this viewpoint, this ratio is 90/10 to 60/4.
More preferably it is 0. [0019] The thermoplastic resin composition of the present invention may optionally added to <br/> components described above were mixed other additives simultaneously or sequentially, to be produced was melt-kneaded by a conventional method it can. For melt kneading, single screw extruder, twin screw extruder, kneader,
It can be performed using a kneader such as a Banbury mixer. The type of equipment to be used and the conditions for melt-kneading are not particularly limited, but the kneading is generally performed at 180 to 270 ° C. for 3 to 30 minutes. The thermoplastic resin composition of the present invention may optionally contain styrene-isoprene having no functional group at a terminal,
Hydrogenated styrene-butadiene block copolymer, styrene-based resins such as polystyrene and ABS, various thermoplastic resins, reinforcing agents such as glass fibers, fillers such as mica and talc, antioxidants, release agents, coloring Agents, ultraviolet absorbers, antistatic agents, nucleating agents, flame retardants and the like. The thermoplastic resin composition of the present invention has the characteristics of maintaining the characteristics inherent to polycarbonate resins and improving the low-temperature impact resistance without delamination. The thermoplastic resin composition of the present invention can be molded by any molding method such as injection molding, extrusion molding, press molding, blow molding, extrusion blow molding, calendar molding, cast molding, and the like. It is possible to manufacture a molded article of any shape and use such as electronic parts, mechanical parts, automobile parts, pipes, sheets, films, daily necessities and the like. The present invention will be described below in more detail with reference to examples, but the present invention is not limited thereto. In the following Examples and Comparative Examples, each polymer is represented by an abbreviation, and the specific contents are shown in Tables 1 and 2 below. [Table 1] (Production of a block copolymer having a hydroxyl group at the terminal) Production Examples 1 and 2, styrene, isoprene, and styrene were polymerized in cyclohexane in the order of s-butyllithium as an initiator, and after the polymerization was completed, 10 times the polymerization active terminal. By adding ethylene oxide in a molar amount, a styrene-isoprene-styrene block copolymer having a hydroxyl group at one end of the molecular chain was obtained. This was further hydrogenated to obtain SEPS-OH (I) having a terminal hydroxyl group. Also, by changing the amount of the monomer used, SEPS-OH
(II) was obtained. Table 2 shows the molecular characteristics. Preparation Example 3 SEBS-OH (III) was obtained in the same manner as in Preparation Example 1 except that butadiene was used instead of isoprene. Production Example 4 Production Example 1 without addition of ethylene oxide after completion of polymerization
A block copolymer having no functional group at the terminal in the same manner as
SEPS ( IV ) was obtained. [Table 2] (Examples 1 to 6, Comparative Examples 1 to 3) Each of the polymers shown in Tables 1 and 2 was blended at 250 ° C by a twin-screw extruder at a weight ratio shown in Table 3 below.
A test piece was prepared from the obtained composition by injection molding at 270 ° C., and the flexural strength was measured in accordance with JIS K7113, and the impact resistance at −20 ° C. at room temperature using an Izod tester was measured. The state of delamination was determined by visually observing the cross section of the test piece. As a result, the results shown in Table 3 below were obtained. [Table 3] The results in Table 3 above show that the compositions according to the present invention have improved low temperature impact resistance. When the thermoplastic resin composition of the present invention is used, it is possible to improve the low-temperature impact resistance of a polycarbonate resin without delamination.

(56) References JP-A-6-65466 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 53/02 C08L 69/00

Claims (1)

(57) [Claim 1] (a) Polycarbonate resin 95 to 3
0 parts by weight, and at least one selected from the group consisting of (b) a hydrogenated polybutadiene block obtained by hydrogenating a polymer block mainly composed of an aromatic vinyl compound and a polybutadiene having a 1,2-bond amount of 20% or less. One block A, a hydrogenated polyisoprene block, a hydrogenated polybutadiene block obtained by hydrogenating polybutadiene having a 1,2-bond content of 30 to 70%, and a random copolymer of hydrogenated isoprene and butadiene. Modified block copolymer (b-1 ) 5 to 70 having a hydroxyl group at a terminal of a block copolymer containing at least one block B selected from the group consisting of polymer blocks.
A thermoplastic resin composition comprising parts by weight.