Resin blend

Abstract

Disclosed are a resin blend, a copolymer, a pellet, a method of manufacturing a resin-molded article using the same, and a resin-molded article. The exemplary resin blend can be useful in providing a protective film for polarizing plates having excellent adhesive strength to a polarizer. Also, the resin blend can be useful in exhibiting excellent adhesive strength to the polarizer without performing an additional primer coating process on a surface(s) of the protective film for polarizing plate, thereby reducing production time and cost and improving productivity.

Claims

1. A resin blend comprising: a first resin; and a second resin that is an acrylic polymer having a difference in surface energy, melt viscosity or solubility parameter from the first resin, wherein the first resin is a polymer of a monomer blend comprising: an alkyl (meth)acrylate containing an alkyl group having 1 to 14 carbon atoms; a monomer represented by Formula 1; and a monomer represented by Formula 3, wherein the second resin is a polymer of a monomer blend comprising: 47 to 73 parts by weight of an alkyl (meth)acrylate containing an alkyl group having 1 to 14 carbon atoms; 20 to 30 parts by weight of a monomer represented by Formula 1; and 3 to 27 parts by weight of a monomer at least one selected from the group consisting of -butyrolactone (meth)acrylate, N-vinyl pyrrolidone, N-vinyl phthalimide, N-succinimidyl acrylate, norbonene lactone (meth)acrylate, hydroxyethyl (meth)acrylate, N-methylol acrylamide and N-phenyl acrylamide, wherein the second resin has a difference in surface energy of 0.1 to 35 mN/m at 25 C. from the first resin, and wherein the second resin has a difference in melt viscosity of 0.1 to 3,000 Pa*s from the first resin at a shear rate of 100 to 1,000 s.sup.1 and a processing temperature of the resin blend: ##STR00007## wherein R.sub.1 represents hydrogen, or an alkyl group having 1 to 4 carbon atoms, Ar represents a phenyl group, R.sub.2 represents hydrogen, or XR.sub.6, where X represents O, or OC(O), and R.sub.6 represents an alkyl group having 1 to 4 carbon atoms, Y represents oxygen, or NR.sub.10, where R.sub.10 represents hydrogen, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 8 carbon atoms.

2. The resin blend of claim 1, wherein the second resin has a difference in solubility parameter at 25 C. of 0.001 to 10.0 (J/cm.sup.3).sup.1/2 from the first resin.

3. The resin blend of claim 1, wherein the monomer blend for the first resin comprises: 85 to 98 parts by weight of the alkyl (meth)acrylate containing an alkyl group having 1 to 14 carbon atoms; 1 to 5 parts by weight of the monomer represented by Formula 1; and 3 to 10 parts by weight of the monomer represented by Formula 3.

4. The resin blend of claim 1, wherein the monomer of Formula 1 is styrene or -methyl styrene, and the monomer of Formula 3 is a cyclohexyl maleimide or a maleic anhydride.

5. The resin blend of claim 1, wherein R.sub.1 represents hydrogen, or a methyl group, Ar represents a phenyl group, R.sub.2 represents hydrogen, or XR.sub.6, where X represents O, or OC(O), and R.sub.6 represents a methyl group, or an ethyl group.

6. The resin blend of claim 1, wherein the second resin has a molecular weight distribution of 1 to 2.5.

7. The resin blend of claim 1, wherein the second resin has a weight-average molecular weight of 5,000 to 200,000.

8. The resin blend of claim 1, wherein the second resin is included at a content of 0.1 to 50 parts by weight, based on 100 parts by weight of the first resin.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows an SEM image of a layer-separated cross-sectional shape of a resin-molded article prepared in Example 4.

(2) FIG. 2 shows an SEM image of a layer-separated cross-sectional shape of a resin-molded article prepared in Comparative Example 1.

BEST MODE

(3) Hereinafter, the resin blend will be described in further detail with reference to Examples and Comparative Examples. However, it should be understood that the resin blend according to one exemplary embodiment of the resent invention is not limited to the Examples disclosed below.

(4) Elongation films prepared in the following Examples and Comparative Examples were evaluated for physical properties, as follows.

(5) 1. Measurement of Optical Properties (Haze and Transmittance)

(6) Elongation films were measured for haze and transmittance using a haze meter HM-150 (commercially available from Murakami Color Research Laboratory).

(7) 2. Measurement of Melt Viscosity

(8) The elongation films were measured for melt viscosity using a capillary rheometer (Capillary Rheometer 1501 commercially available from Gottfert).

(9) Specifically, a capillary die was attached to a barrel, and a resin obtained in Examples or Comparative Examples was put into the barrel three times. Thereafter, the shear viscosity (Pa*s) of the resin according to a shear rate at a processing temperature of 250 C. was measured.

(10) 3. Measurement of Adhesive Strength

(11) To evaluate an adhesive strength between a polarizer and a protective film in a polarizing plate, a polarizing plate having a width of 18 mm was prepared. Specifically, a polarizing plate was prepared by attaching each of test samples prepared as protective films in Examples and Comparative Examples to a surface of a polarizer, which was prepared by elongating a polyvinyl alcohol-based resin film, staining the resin film with iodine and treating the stained resin film with an aqueous boric acid solution, so that each of the test sample faced toward the polarizer. The prepared polarizing plates were measured for 90 peel strength at a peel rate of 300 mm/min using a Texture analyzer (commercially available from MHK Trading Co.). The peel strength was measured in triplicate, and an average value was recorded.

(12) 4. Section Observation

(13) The test samples prepared in Examples and Comparative Examples were subjected to a low-temperature impact test, and fracture surfaces of the test samples were etched with THF vapor. Thereafter, layer-separated cross-cross-sectional shapes of the test samples were observed using an SEM (commercially available from Hitachi Chemical Co., Model name: S-4800).

(14) The observed cross-cross-sectional shapes were evaluated according to the following evaluation criteria.

(15) : Complete layer separation is observed

(16) : Layer separation is insufficient

(17) x: Layer separation is not observed

(18) 5. Measurement of Surface Energy

(19) Test samples were measured for surface energy using a drop shape analyzer (Trade name: DSA100 commercially available from KRUSS GmbH) according to an Owens-Wendt-Rabel-Kaelble method.

(20) Specifically, 15% by weight of each of the resins obtained in Examples or Comparative Examples was dissolved in a methyl ethyl ketone solvent, and an LCD glass was then bar-coated with the resulting resin solution. Thereafter, the coated LCD glass was pre-dried at 60 C. for 2 minutes in an oven, and dried at 90 C. for one minute in the oven.

(21) After the drying (or curing), each of deionized water and diiodomethane was dropped 10 times on the coated surface, and an average value of contact angles was calculated, and then applied to the Owens-Wendt-Rabel-Kaelble method to calculate surface energy.

Preparative Example: Preparation of Second Resins

Preparative Example 1

(22) 1,144 g of a solvent, methyl ethyl ketone, and 520 g of methyl methacrylate (MMA), 200 g of styrene and 80 g of -butyrolactone methacrylate (GBLMA) as monomers, and 0.4 g of a chain transfer agent, n-dodecyl mercabtane (n-DDM), were put into a reactor, and a nitrogen atmosphere was formed. Thereafter, 1.6 g of an initiator, azobisisobutyronitrile (AIBN), was added into the reactor, and the resulting blend was stirred at a rate of 400 rpm. Polymerization was performed at a reaction temperature of 70 C. for 18 hours, and the resulting polymerization product was precipitated in normal hexane, repeatedly washed and dehydrated three times, and dried at 80 C. in an oven.

Preparative Example 2

(23) A second resin was prepared in the same manner as in Preparative Example 1, except that 440 g of methyl methacrylate, 200 g of styrene, and 160 g of -butyrolactone methacrylate were used as the monomers.

Preparative Example 3

(24) A second resin was prepared in the same manner as in Preparative Example 1, except that 560 g of methyl methacrylate, 200 g of styrene, and 40 g of 2-hydroxyethyl methacrylate (2-HEMA) were used as the monomers.

Preparative Example 4

(25) A second resin was prepared in the same manner as in Preparative Example 1, except that 400 g of methyl methacrylate, 200 g of styrene, 160 g of -butyrolactone methacrylate, and 40 g of 2-HEMA were used as the monomers.

Preparative Example 5

(26) A second resin was prepared in the same manner as in Preparative Example 1, except that 520 g of methyl methacrylate, 200 g of styrene, and 80 g of N-vinyl pyrrolidone were used as the monomers.

Preparative Example 6

(27) A second resin was prepared in the same manner as in Preparative Example 1, except that 400 g of methyl methacrylate, 200 g of styrene, 160 g of -butyrolactone methacrylate, and 40 g of N-vinyl pyrrolidone were used as the monomers.

Preparative Example 7

(28) A second resin was prepared in the same manner as in Preparative Example 1, except that 600 g of methyl methacrylate, and 200 g of styrene were used as the monomers.

Preparative Example 8

(29) A second resin was prepared in the same manner as in Preparative Example 1, except that 280 g of methyl methacrylate, 200 g of styrene, and 320 g of -butyrolactone methacrylate were used as the monomers.

Preparative Example 9

(30) A second resin was prepared in the same manner as in Preparative Example 1, except that 360 g of methyl methacrylate, 200 g of styrene, 160 g of -butyrolactone methacrylate, and 80 g of 2-HEMA were used as the monomers.

Preparative Example 10

(31) A second resin was prepared in the same manner as in Preparative Example 1, except that 360 g of methyl methacrylate, 200 g of styrene, 160 g of -butyrolactone methacrylate, and 80 g of N-vinyl pyrrolidone were used as the monomers.

Example 1

(32) 90 parts by weight of a first resin (a thermoplastic resin including methyl methacrylate at 91 parts by weight, cyclohexyl maleimide at 6 parts by weight, and -methyl styrene at 3 parts by weight) was mixed with 10 parts by weight of the second resin prepared in Preparative Example 1, and the resulting mixture was extruded at a temperature of 250 C. in a twin-screw extruder (commercially available from Leistritz Corp.) to obtain a pellet. Thereafter, such a pellet was extruded at a temperature of 250 C. in an extruder having a T-die gap of 1 t (commercially available from EM Industries, Inc.) to prepare an extrusion film having a film thickness of approximately 180 to 210 m. The extrusion film was biaxially elongated in machine (MD) and traverse (TD) directions at a temperature of 135 C. to prepare an elongation film having a thickness of approximately 50 m.

Example 2

(33) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 2 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Example 3

(34) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 3 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Example 4

(35) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 4 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Example 5

(36) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 5 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Example 6

(37) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 6 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Comparative Example 1

(38) 100 parts by weight of a pellet of the first resin used in Example 1 was dried in an oven, and the pellet was extruded in the same manner as in Example 1 to prepare an extrusion film. The extrusion film was elongated in the same manner as in Example 1 to prepare an elongation film.

Comparative Example 2

(39) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 7 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Comparative Example 3

(40) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 8 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Comparative Example 4

(41) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 9 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Comparative Example 5

(42) A test sample was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparative Example 10 was mixed with 90 parts by weight of the same first resin as used in Example 1.

(43) TABLE-US-00001 TABLE 1 Difference Difference in surface Adhesive in melt energy Optical properties strength Phase viscosity (mN/m) Haze T (%) (N/cm.sup.2) separation (Pa*s) Example 1 6 0.2 93.8 2.8 1,120 Example 2 5 0.2 93.7 3 1,210 Example 3 5 0.2 93.9 2.6 1,075 Example 4 7 0.2 93.7 3.5 1,200 Example 5 5 0.2 93.8 2.5 1,205 Example 6 6 0.2 93.7 3.4 1,200 Comparative 0.3 93.7 2 x Example 1 Comparative 5 0.3 93.8 2.5 1,010 Example 2 Comparative 6 1,250 Example 3 (unelongatable) (unelongatable) (unelongatable) Comparative 7 1,205 Example 4 (unelongatable) (unelongatable) (unelongatable) Comparative 5 1,195 Example 5 (unelongatable) (unelongatable) (unelongatable)