JPH11228755A - Surface protection film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a surface protection film which has a high adhesion property, shows little staining property against the articles to be protected and has a high transparency. SOLUTION: The film comprises an ethylene/α-olefin copolymer composition containing from 80 to 99.5 wt.% ethylene/α-olefin copolymer component having the following characteristics (a-1)-(a-5) and from 20 to 0.5 wt.% high-density polyethylene component. (a-1) The carbon number of the α-olefin is from 3 to 12, (a-2) the melt flow rate(MFR) is from 0.1 to 50 g/10 min, (a-3) the density (d) is from 0.880 to 0.935 g/cm<3> , (a-4) the coefficient of variation of composition distribution Cx, defined as Cx=σ/SCB ave. [σ: standard deviation of composition distribution, SCB ave.: average of short-chain branching per 1,000 (1/1,000C)], is 0.5 or smaller, and (a-5) the weight ratio (a) (wt.%) of the cold xylene soluble portion is smaller than 4.8×10<4> ×(0.95-d)<3> +10<6> ×(0.95-d)<4> +1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface protection film. More specifically, the present invention relates to a surface protective film suitable for protecting the surface of an article, comprising a resin composition containing a specific ethylene / α-olefin copolymer and low-density polyethylene or high-density polyethylene by a high-pressure radical polymerization method. .

[0002]

2. Description of the Related Art In general, a surface protective film is formed by attaching an adhesive film to the surface of an article by an adhesive force, thereby causing scratches due to contact or friction of the article from the outside during storage and transportation of the article, dust, and the like. It is used to prevent contamination of the surface due to adhesion of such as. Specifically, it is used for surface protection of metal plates such as aluminum and stainless steel, synthetic resin plates such as acryl and engineering plastic, and wood decorative plates used for industrial and architectural uses. The properties required of the films used for surface protection include high self-adhesiveness, excellent transparency, and low contamination to articles. Conventionally, ethylene-α-
Films composed of olefin copolymers have been used. Ethylene-α-olefin copolymers with solid catalysts contain low molecular weight components with adhesive properties, so they have good adhesiveness, but depending on the environment such as long-term storage or storage at high temperatures, Since low molecular weight bleeds migrate from the film to the surface, there is a problem of contamination of the protected article. In addition, recently found polyethylene having a uniform structure represented by a metallocene-based catalyst-based ethylene / α-olefin copolymer has a drawback of low contamination to articles, but poor adhesion.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a surface protective film which is excellent in tackiness, has low contamination to a protected article, and is excellent in transparency.

[0004]

SUMMARY OF THE INVENTION The present inventors have for many years eagerly been concerned with materials that are tacky, less contaminating, and have superior transparency to protected articles that are important as surface protection films. I have been studying. As a result, a specific ethylene / α-olefin copolymer, and found that a surface protective film made of a resin composition containing low-density polyethylene or high-density polyethylene by a high-pressure radical polymerization method achieves the object of the present invention, The present invention has been completed.

That is, the present invention provides the following (a-1) to (a-
80 to 99.5% by weight of an ethylene / α-olefin copolymer (A) component having the property of 5), and 20 to 0.5% of a low density polyethylene (B) component by a high-pressure radical polymerization method.
% By weight or high density polyethylene (C) component 20-0.
A surface protective film comprising an ethylene / α-olefin copolymer composition containing 5% by weight. Component (A): (a-1) carbon number of α-olefin: 3 to 12 (a-2) melt flow rate (MFR): 0.1 to 50 g
/ 10 min (a-3) Density (d): 0.880 to 0.935 g / cm ³ (a-4) Composition distribution variation coefficient Cx defined by the following equation (1)
Is 0.5 or less Cx = σ / SCBave. Equation (1) σ: Standard deviation of composition distribution SCBave .: Average value of short-chain branching per 1000C (1 /
(1000C) (a-5) The weight ratio a (wt%) of the cold xylene-soluble portion is the density d.
A <4.8 × 10 ⁴ × (0.95-d) ³ +10 ⁶ × (0.95-d) ⁴ +1 which satisfies the relational expression (2) Expression (2) Hereinafter, the present invention will be described in detail.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Ethylene / α used in the present invention
The olefin copolymer (A) component is a copolymer of ethylene and one or more (a-1) α-olefins having 3 to 12 carbon atoms. Specific examples of these copolymer components include propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1, nonene-1, decene-1, dodecene-1, 4-methyl-pentene. -1, 4
-Methyl-hexene-1, vinylcyclohexane, vinylcyclohexene, styrene, norbornene, butadiene, isoprene and the like, but the present invention is not limited to the above compounds. Among these, butene-1, hexene-1, octene-1, and 4-methyl-pentene-1 are preferred.

The ethylene / α-olefin copolymer comprises:
(A-2) Melt flow rate (MFR) of 0.1 to 5
0g / 10 min, and its (a-3) density is 0.880.
0.935 g / cm ³ .

In the present invention, the melt flow rate (MF)
R) means a load of 2.16 kg and a measurement temperature of 190 ° C. according to the method specified in JIS K6760-1981.
Is a value measured under the condition of If this value is less than 0.1 g / 10 minutes, the extrusion load increases in film forming and the surface of the film becomes rough, which is not preferable because the adhesiveness decreases. On the other hand, when this value exceeds 50 g / 10 minutes, the strength of the film is greatly reduced, which is not preferable. The preferred range of the melt flow rate is 0.3 to 20.
g / 10 minutes, more preferably 0.5 to 10 g / 10 minutes,
Most preferably, it is 0.8 to 5 g / 10 minutes.

The ethylene / α-olefin copolymer weight referred to here
The density (d) of the coalescence is defined by JIS K6760-1981.
It is measured by the method specified in. The density is 0.88
0 g / cm^ThreeIf it is smaller than this, the rigidity is too low
Used as a packaging film for handling
Not suitable for On the other hand, the density is 0.935 g / cm
^ThreeIf it is larger than this, transparency and impact strength will decrease.
Not preferred. The preferred density is 0.890-0.9
30g / cm^Three, More preferably 0.895 to 0.9
25g / cm^ThreeIt is.

The ethylene / α-olefin copolymer used in the present invention satisfies the following (a-4) and (a-5). (a-4) Composition distribution variation coefficient Cx defined by the following equation (1)
Is 0.5 or less Cx = σ / SCBave. Equation (1) σ: Standard deviation of composition distribution SCBave .: Average value of short-chain branching per 1000C (1 /
(1000C) (a-5) The weight ratio a (wt%) of the cold xylene-soluble portion is the density d.
A <4.8 × 10 ⁴ × (0.95-d) ³ +10 ⁶ × (0.95-d) ⁴ +1 which satisfies the relational expression (2) with (g / cm ³ ) Expression (2)

The composition distribution variation coefficient Cx referred to here indicates a measure of the composition distribution, and the smaller the value, the narrower the composition distribution. When the composition distribution variation coefficient Cx is 0.
It is preferably 5 or less, which gives an excellent result in the balance between transparency and tackiness of the surface protective film of the present invention. If the composition distribution variation coefficient Cx exceeds 0.5, the strength may decrease, and the adhesiveness and transparency may be poor.

The outline of the measurement of the composition distribution variation coefficient Cx is as follows. The ethylene / α-olefin copolymer (A) component used in the present invention is dissolved in a solvent heated to a predetermined temperature, put into a column in a column oven, and the oven temperature is lowered. Subsequently, the temperature is raised to a predetermined temperature, and the relative concentration and short-chain branching degree of the copolymer distilled out during that time are measured by FT-IR connected to a column. The temperature is raised to the final temperature while obtaining the relative concentration and short-chain branching degree of the copolymer distilled out during that time. A composition distribution curve is determined from the obtained relative concentration and the degree of short-chain branching. The standard deviation of the composition distribution curve was σ, and the average branching degree (Σ (SCB × the ratio of the amount of elution with each SCB)) was SCBave, and the composition distribution variation coefficient Cx was calculated by the above equation.

[0013] The cold xylene-soluble part mentioned here is
code of federal regulations, Food and Drugs Admini
It is measured by the method specified in §175.1520 of stration. It is preferable to use an ethylene / α-olefin copolymer in which the weight ratio a of the cold xylene-soluble portion satisfies the above range, and excellent results are obtained in the balance between transparency and mechanical strength of the resin composition used in the present invention. give. When the weight ratio a of the cold xylene-soluble portion is larger than the range shown in the above formula, the strength is reduced and the contamination of the protected article is increased. A more preferable range of a is the formula (6)
, Most preferably the range of equation (7). a <4.8 × 10 ⁴ × (0.95-d) ³ +10 ⁶ × (0.95-d) ⁴ Equation (6) a <4.8 × 10 ⁴ × (0.95-d) ³ Equation (7) (where a is a cold The weight ratio a (% by weight) of the xylene-soluble part and d represent the density (g / cm ³ ) of the ethylene / α-olefin copolymer.)

The ethylene / α-olefin copolymer satisfying these more preferable conditions is produced by a catalyst containing a transition metal compound, and particularly a catalyst comprising a transition metal compound having a group having a cyclopentadiene type anion skeleton. Those produced in the presence are preferred. The transition metal compound is a so-called metallocene compound, usually,
In the formula ML _a X _na (wherein, M is a transition metal atom of Group 4 or Lanthanide series of the Periodic Table of Elements .L is a group containing a group or a hetero atom having a cyclopentadiene type anion skeleton , At least one is a group having a cyclopentadiene-type anion skeleton, a plurality of Ls may be cross-linked to each other, X is a halogen atom, hydrogen or a hydrocarbon group having 1 to 20 carbon atoms, and n is a transition. Represents the valence of a metal atom, and a is an integer satisfying 0 <a ≦ n.) And can be used alone or in combination of two or more. Further, the catalyst may include an organic aluminum compound containing an alumoxane compound and / or an ionic compound such as trityl borate and anilinium borate, and / or SiO ₂ , Al ₂
It is used in combination with a particulate carrier including an inorganic carrier such as O _{3 and} an organic polymer carrier such as an olefin polymer such as ethylene and styrene. However, the catalyst for producing the ethylene / α-olefin copolymer used in the present invention is not limited to the above compounds. The polymerization method is not particularly limited, and examples thereof include a gas phase polymerization method, a liquid phase polymerization method, and a high pressure ionic polymerization method, and a gas phase polymerization method is particularly preferable.

The low-density polyethylene (B) component obtained by the high-pressure radical polymerization method used in the present invention is generally used in a tank reactor or a tube reactor in the presence of a radical generator.
Polymerization pressure 1400-3000 kg / cm ² , polymerization temperature 2
It is produced by polymerizing ethylene under the condition of 00 to 300 ° C. The melt flow rate can be adjusted by using a hydrocarbon such as hydrogen, methane, or ethane as a molecular weight modifier.

The low-density polyethylene (B) component obtained by the high-pressure radical polymerization method used in the present invention has (b-1) a melt flow rate (MFR) of 0.2 to 20 g / 10 minutes and a (b-2) density of (b-2). Those satisfying 0.910 to 0.935 g / cm ³ are preferable.

In the present invention, the melt flow rate is J
According to the method specified in IS K6760-1981, the load was 2.16 kg, and the measurement temperature was a value measured at 190 ° C. A more preferred melt flow rate range is 0.35 to 10 g / 10 min, most preferably 0.4 to 10 g / 10 min.
５5 g / 10 min.

The above density is defined in JIS K6760-19.
It is measured by the method specified in 81. More preferred density 0.915~0.930g / cm ^3, most preferably from 0.918~0.925g / cm ^3.

Further, the low-density polyethylene (B) component obtained by the high-pressure radical polymerization method used in the present invention comprises the (b-
3) The swell ratio (SR) is the melt flow rate (MFR)
It is preferable to satisfy the relational expression (Expression 3). 1.81 × 10 ⁻¹ × log (MFR) +1.58>SR> 1.29 (Equation 3) Regarding the structure of low-density polyethylene by high-pressure radical polymerization, the average molecular weight, molecular weight distribution, long-chain branching degree, etc. are controlled by the polymerization conditions. It is possible. The swell ratio (SR) used here is an index indicating the degree of long-chain branching, and is determined according to JIS K7210. The swell ratio (SR) of the low density polyethylene by the high pressure radical polymerization method used in the present invention is the melt flow rate
The effect of the present invention can be further exhibited when a specific range satisfying the relational expression with (MFR) is used.

High density polyethylene (C) used in the present invention
The component (c-1) has a melt flow rate of 0.2 to 20.
g / 10 min, (c-2) the density is 0.940 g / cm ³ or more, and (c-3) the value of [g] ^* defined by the following formula (4) is 0.2 to 0.8. High density polyethylene is preferred. [G] ^* = [η] / [η] _l Equation (4) where [η] represents the intrinsic viscosity of the component (C) measured with a tetralin solution at 135 ° C., and [η] _l is the component (C) Is the limiting viscosity of the linear high-density polyethylene having the same weight average molecular weight as that obtained by the following formula (5). [Η] _l = 4.86 × 10 ⁻⁴ [Mw] ^0.705 Formula (5) Here, [Mw] is the weight average molecular weight (GP) of the component (C).
C-LALLS method).

The melt flow rate of the high-density polyethylene (C) component is more preferably 0.5 to 10 g / 10 minutes. The density of the high-density polyethylene is more preferably 0.945 to 0.955 g / cm ³ . The value of [g] ^* defined by the above formula (4) for high-density polyethylene is
More preferably, it is 0.3 to 0.6. The weight average molecular weight of the component (C) is GPC-LALLSS (Gel Permiation Chr
omatography-Low Angle Laser Light Scatterring method)
Is measured by Equation (5) is described, for example, in the literature (H. Rachapudy, GGSmith, VRRaju, and WW
Glassley, J. Polym. Sci., Polym. Phys. Ed., 17, 1211 (19
79)). The method for obtaining the high-density polyethylene (C) component includes, for example, the following method. That is, ethylene alone, or ethylene and a small amount of an α-olefin having 3 to 18 carbon atoms, using a Ziegler-Natta catalyst or a metallocene catalyst, in the presence or absence of a solvent, gas-solid, liquid- Polymerizes under a solid or homogeneous liquid layer. The polymerization temperature is usually from 30 to 300 ° C, and the polymerization pressure is from normal pressure to
3000 kg / cm ² . In addition, it can be selected from those commercially available as high-density polyethylene.

The proportion of each component in the ethylene / α-olefin copolymer composition used in the present invention is ethylene / α-olefin.
-80 to 99.5% by weight, preferably 90 to 99% by weight, more preferably 95% by weight of the olefin copolymer (A) component.
-99% by weight, 20-0.5% by weight, preferably 10-1% by weight, more preferably 5-1% by weight, of the low-density polyethylene (B) component or the high-density polyethylene (C) component by a high-pressure radical polymerization method. is there. If the content of the component (B) or the component (C) exceeds 20% by weight, a satisfactory impact strength as a surface protective film cannot be obtained,
On the other hand, if it is less than 0.5% by weight, it is not possible to obtain a desired balance between excellent tackiness and low contamination.

In producing the surface protective film of the present invention, the ethylene / α-olefin copolymer (A) component and the low-density polyethylene (B) component or the high-density polyethylene (C) component obtained by high-pressure radical polymerization are used. Is dry-blended or melt-blended, and then the composition is made into a surface protective film using an inflation film production apparatus or a T-die cast film production apparatus. Various blenders such as a Henschel mixer and a tumbler mixer are used for the dry blending, and various mixers such as a single screw extruder, a twin screw extruder, a Banbury mixer and a hot roll are used for the melt blending. In addition, the surface protective film of the present invention employs an ethylene / α-olefin copolymer composition comprising each component by employing a technique such as coextrusion or extrusion coating (also referred to as extrusion lamination). Can be used as a multilayer film. However, in this case,
The component to be the surface protective film of the present invention must be at least a surface layer.

The surface protective film of the present invention may be used with various resins other than the components (A) and (B) or (C) as long as the effects of the present invention are not impaired. May be blended. For example, polyolefin-based resins such as low-density elastomers can be used to improve impact strength, and these can be used alone or in combination of two or more.

In order to further improve the physical properties of the surface protective film of the present invention, 2,6-di-t-butyl-p-cresol (BHT) and tetrakis [methylene-
3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane (IRGANOX 101
0), n-octadecyl-3- (4'-hydroxy-
A phenolic stabilizer represented by 3,5′-di-t-butylphenyl) propionate (IRGANOX 1076); bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite and tris (2,2)
Phosphite-based stabilizers represented by 4-di-t-butylphenyl) phosphite; lubricants represented by higher fatty acid amides and higher fatty acid esters; glycerin esters and sorbitanate esters of fatty acids having 8 to 22 carbon atoms; polyethylene An antistatic agent such as a glycol ester; and a processability improver represented by a fatty acid metal salt such as calcium stearate may be contained.

[0026]

Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples. The evaluation method is as follows. (1) Density (d) According to the method specified in JIS K6760. (2) Melt flow rate (MFR) According to the method specified in JIS K6760. The load is 2.16 kg and the temperature is 190 ° C. (3) Composition distribution variation coefficient (Cx) It was measured using a multifunctional LC manufactured by Tosoh Corporation. The ethylene / α-olefin copolymer used in Examples and Comparative Examples was 14
The resin was dissolved in an orthodichlorobenzene solvent heated to 0 ° C, placed in a column filled with sea sand in a column oven, and the temperature of the oven was lowered to -14 ° C. Subsequently, the temperature was raised to a predetermined temperature, and the relative concentration and the degree of branching of the copolymer flowing out during that time were measured by FT-IR connected to a column. The temperature was raised to the final temperature while obtaining the relative concentration and the degree of branching of the copolymer flowing out at each set temperature. A composition distribution curve was obtained from the obtained relative concentration and the degree of branching, and a composition distribution variation coefficient Cx representing the average composition and the breadth of the distribution was obtained from the curve. (4) Cold xylene soluble part (a) US code of federal regulations, Food and Drugs
The method specified in §175.1520 of the Administration was followed. (5) Swell ratio (SR) The diameter D of the extruded strand was measured at the time of melt flow rate measurement using a melt flow rate measurement device specified in JIS K7210, and the ratio D / D ₀ to the orifice diameter D ₀ was determined. The swell ratio was determined. Measurement temperature is 19
Performed at 0 ° C. (6) [g] ^* Connect a Chromatix LALLS device (KMX-6) to a Tosoh GPC device (HLC811), solvent tetralin, concentration = 0.5% by weight, temperature = 140 ° C., flow rate = 1 ml / Measured in minutes. (7) Haze (haze degree) The haze was measured according to the method defined in ASTM D1003. The smaller the value, the better the transparency. (8) Adhesiveness The processed film was slit into 400 mm width, rewound around a paper tube, and adjusted at 23 ° C. for 18 hours.
Then, the sample for the temperature 23 ° C. taken out in a state in close contact from the paper tube in two upper and lower, under the conditions of 50% RH, using a vertical peelable blocking tester, the load movement speed 20 g / min 100 cm ² A peeling force was applied to the contact portion, and a force (g / 100 cm ² ) required for peeling was measured. The higher the value, the higher the adhesive strength and the better the stretch film. (9) Stain resistance Three films each having a size of 15 cm × 15 cm and a thickness of 18 μm were laminated on an aluminum plate having a mirror surface and treated in an oven at 60 ° C. for 7 days. After the treatment, the aluminum plate and the film were peeled off, and the surface of the aluminum plate was visually observed to evaluate the degree of contamination. Evaluation was made on a scale of 1 to 3 from those with little contamination. 1: No spots due to contamination are seen at all. 2 ... Spots due to contamination are slightly observed. 3: Many spots due to contamination are seen on the surface.

Table 1 shows the properties of the ethylene / α-olefin copolymer (A) used, Table 2 shows the properties of the low-density polyethylene (B) obtained by the high-pressure radical polymerization method, and Table 2 shows the properties of the high-density polyethylene (C). Are shown in Table 3.

Examples 1 to 5 and Comparative Examples 1 to 4 The components (A) and (B) or (C)
By mixing with a tumble mixer to obtain the composition shown in Table 5, an ethylene / α-olefin copolymer resin composition was obtained,
This was extruded from a modern machinery 40 mm / 50 mm co-extruder (L / D = 32), die 600 mm wide, lip 0.
9mm width, processing temperature 280 ° C by T-die processing machine,
An 18 μm thick film was processed under the conditions of an extrusion rate of 34 kg / h, a chill roll temperature of 30 ° C., and a take-up speed of 75 m / min. Tables 4 and 5 show the physical properties of the obtained films.

[0029]

[Table 1] (Note 1) 4.8 × 10 ⁴ × (0.95-d) ³ +10 ⁶ × (0.95-d) ⁴ +1 A1: Made by Evolu Japan, sold by Sumitomo Chemical Co., Ltd.
Sumikasen E FV403 A2: manufactured by Nippon Evolu Co., Ltd., sold by Sumitomo Chemical Co., Ltd.
Sumikasen E FV402 A3: Sumikasen α FZ202, manufactured by Sumitomo Chemical Co., Ltd.
-0 A4: Sumikasen α FZ201, manufactured by Sumitomo Chemical Co., Ltd.
-0 A1 to A4 are all ethylene-hexene-1 copolymers

[0030]

[Table 2] (Note 2) 1.81 × 10 ^-1 × log (MFR) +1.58 B1, B2: Sumikasen, manufactured by Sumitomo Chemical Co., Ltd., manufactured by high-pressure radical polymerization

[0031]

[Table 3] C1: Idemitsu Petrochemical Co., Ltd., Idemitsu Polyethylene 440
MC2: manufactured by Maruzen Polymer Co., Ltd., Chemiretz 2010

[0032]

[Table 4]

[0033]

[Table 5]

[0034]

As described above in detail, according to the present invention, a surface protective film having remarkably excellent transparency and adhesiveness and excellent contamination resistance can be provided as compared with the conventional surface protective film.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 23:06)

Claims (3)

[Claims] An ethylene / α-olefin copolymer (A) component having the following properties (a-1) to (a-5): 80 to 99.
An ethylene / α-olefin copolymer containing 5% by weight and 20 to 0.5% by weight of a low density polyethylene (B) component or 20 to 0.5% by weight of a high density polyethylene (C) component by a high pressure radical polymerization method A surface protective film comprising a composition. Component (A): (a-1) carbon number of α-olefin: 3 to 12 (a-2) melt flow rate (MFR): 0.1 to 50 g
/ 10 min (a-3) Density (d): 0.880 to 0.935 g / cm ³ (a-4) Composition distribution variation coefficient Cx defined by the following equation (1)
Is 0.5 or less Cx = σ / SCBave. Equation (1) σ: Standard deviation of composition distribution SCBave .: Average value of short-chain branching per 1000C (1 /
(1000C) (a-5) The weight ratio a (wt%) of the cold xylene-soluble portion is the density d.
A <4.8 × 10 ⁴ × (0.95-d) ³ +10 ⁶ × (0.95-d) ⁴ +1 which satisfies the relational expression (2) with (g / cm ³ ) Expression (2) 2. The surface protective film according to claim 1, wherein the low-density polyethylene (B) component obtained by the high-pressure radical polymerization method has the following properties (b-1) to (b-3). Component (B): (b-1) Melt flow rate (MFR): 0.2 to 20 g
/ 10 min (b-2) Density (d): 0.910 to 0.935 g / cm ³ (b-3) The swell ratio (SR) is expressed by the following relational expression (3) with the melt flow rate (MFR). Satisfy 1.81 × 10 ^-1 × log (MFR) +1.58>SR> 1.29 Equation (3) 3. The high-density polyethylene (C) component has the following (c)
The surface protective film according to claim 1, which has the properties of -1) to (c-3). Component (C): (c-1) Melt flow rate (MFR): 0.2 to 20 g
/ 10 min (c-2) Density (d): 0.940 g / cm ³ or more (c-3) The value of [g] ^* defined by the following formula (4) is 0.2
-0.8 [g] ^* = [η] / [η] _l Equation (4) where [η] represents the intrinsic viscosity of component (C) measured with a tetralin solution at 135 ° C., and [η] _l is The intrinsic viscosity of a linear high-density polyethylene having the same weight average molecular weight as the component (C), and is determined by the following formula (5). [Η] _l = 4.86 × 10 ⁻⁴ [Mw] ^0.705 Formula (5) Here, [Mw] is the weight average molecular weight (GP) of the component (C).
C-LALLS method).