JPH0262568B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD OF THE INVENTION The present invention relates to a method for producing a fluorinated acrylic multistage copolymer resin having excellent weather resistance, solvent resistance, water and oil repellency, high elongation, and transparency. To explain in more detail, application at room temperature -
High resistance to elongation failure in strain tests,
The present invention also relates to a method for producing a fluorinated acrylic multi-stage copolymer resin having excellent weather resistance, solvent resistance, and water and oil repellency. The multistage polymer resin obtained by the method of the present invention is useful as a weather-resistant film and a sheath material for optical fibers. Prior Art Fluorinated acrylic resins, particularly fluorinated alkyl methacrylate polymers, are used in optical materials that take advantage of their beautiful appearance, outstanding transparency, and low refractive index. Also, since it is water and oil repellent,
It is also used as a fiber treatment agent, and recently SR
(SoilRelease) Used as a processing agent. On the other hand, among fluorinated acrylic polymers, lower fluorinated alkyl methacrylate homopolymers in particular have the characteristics of being hard and brittle, so when used for special purposes, it is difficult to impart elasticity to them. is desired, and various studies have been made for this purpose. As mentioned above, as a method of imparting elasticity to fluorinated acrylic resin, higher fluorinated alkyl methacrylate, such as 3,3,4,4,
5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10,
A copolymer of 10,10-heptadecafluorodecyl methacrylate (hereinafter abbreviated as 17FMA) and methyl methacrylate or fluorinated alkyl methacrylate, and/or an elastic polymer (polyvinylidene fluoride, vinylidene fluoride-tetra A method of blending polymethyl methacrylate with fluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, etc. has been carried out. The former, 17FMA, is a polymer whose main component is a methacrylate vinyl monomer with a long-chain fluorinated alkyl group in the side chain, and its homopolymer has a low refractive index, but it does not change at room temperature. It is rubber-like and difficult to mold, so we improved processability by copolymerizing methyl methacrylate with a relatively high Tg or fluorinated alkyl methacrylate with a relatively high Tg. This is what keeps the rate constant. However, this method is difficult because higher fluorinated methacrylates are currently expensive on the market, and the resulting copolymer has unsatisfactory elongation at low temperatures due to the simple structure of the copolymer. There are drawbacks such as being In the case of the latter elastic polymer, it is a rubber elastic body with a high degree of fluorination and is a vinylidene fluoride derivative that exhibits extremely specific compatibility with polymethyl methacrylate or polyfluorinated alkyl methacrylate. and polymethyl methacrylate, a high range of blend component regions is possible and a transparent resin body with a low refractive index is obtained. However, since vinylidene fluoride derivatives are crystalline polymers, their crystallinity increases when heated, resulting in a major drawback in that the transparency of the blend resin decreases. Currently, it is used as a molding material such as an injection molding material while retaining such defects. That is, the heat resistance of the above blended resin is an extremely important property when used alone as a film or sheet or as a laminated material on other base materials.If heating causes softening or whitening due to crystallization, This will cause a significant decrease in the product value. In view of the current situation, the present inventors further investigated the structure of the polymer itself in detail, and aimed to obtain a multi-stage copolymer resin that is particularly excellent in high elongation, as well as excellent in heat resistance, weather resistance, and low refractive index. As a result of intensive studies, the present invention was completed. OBJECT AND SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a fluorinated acrylic multi-stage copolymer resin that has excellent elongation, excellent heat resistance and weather resistance, and a low refractive index. The method for producing a fluorinated acrylic multi-stage copolymer resin of the present invention includes the following steps: (a) having 50 to 100% by weight of fluorinated alkyl methacrylate A ₁ and 0 to 50% by weight of ethylenic double bonds; 1 to 25 parts by weight of the innermost polymer layer A is obtained by polymerizing with at least one member selected from the group consisting of other monomers A ₂ , polyfunctional monomers A ₃ and graft cross-agents A ₄ . (b) 50-100% by weight of at least one member B ₁ selected from fluorinated alkyl acrylates and fluorinated alkyl methacrylates, and 0-50% by weight of
Other monomers B ₂ with ethylenic double bonds,
Polymerized with at least one member selected from the group consisting of polyfunctional monomer B ₃ and graft cross-agent B ₄ and having a glass transition point Tg of 0° C. or lower,
(c) 50-100% by weight of fluorinated alkyl methacrylate C ₁ and 0-50% by weight of other ethylenic double bonds. a step of polymerizing monomer C ₂ to form an outermost polymer layer C having a glass transition point Tg of 50° C. or higher and having an amount of 19 to 93 parts by weight; and (d) 50 to 100% by weight of at least one member selected from the group consisting of fluorinated alkyl acrylate and fluorinated alkyl methacrylate, and ₀ to 50
% by weight of at least one member selected from the group consisting of another monomer D ₂ having an ethylenic double bond and a grafting agent D ₃ to obtain a glass transition point of the rubber elastic polymer layer B. Tg higher than the glass transition point Tg of the outermost polymer layer C
forming an intermediate polymer layer D of 1 to 75 parts by weight having a lower glass transition point Tg;
Step (b) of forming the rubber elastic polymer layer B, step (d) of forming the intermediate polymer layer D, and step (c) of forming the outermost polymer layer C, and step (b) , (d) and
The polymerization operations in each of (c) are carried out in the presence of the polymer formed by its preceding step, such that the polymer layer of each step is the same as the polymer layer obtained by its preceding step. A monomer (A ₂ ,
B ₂ , C ₂ and D ₂ ) are lower alkyl (meth)acrylate, lower alkoxy (meth)acrylate, cyanoethyl (meth)acrylate, acrylamide, acrylic acid, methacrylic acid, styrene, alkyl-substituted styrene, acrylonitrile and methacrylate. The polyfunctional monomer (A ₃ and B ₃ ) having an ethylenic double bond is selected from the group consisting of nitriles, ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene selected from the group consisting of glycol dimethacrylate, propylene glycol dimethacrylate, divinylbenzene, trivinylbenzene and alkylene glycol diacrylate, and said grafting cross-agent (A ₄ , B ₄ and D ₃ )
It is characterized in that it is selected from the group consisting of allyl, methallyl and crotyl esters of α-, β-unsaturated carboxylic acids and dicarboxylic acids, triallyl cyanurate and triallyl isocyanurate. Another method for producing a fluorinated acrylic multi-stage polymer resin of the present invention includes the following steps: (a) 50 to 100% by weight of fluorinated alkyl methacrylate A ₁ and 0 to 50% by weight of ethylenic double bonds. 1 to ₂₅ parts by weight of _the innermost _polymer layer A (b) 50-100% by weight of at least one member _B1 selected from fluorinated alkyl acrylates and fluorinated alkyl methacrylates, and 0-50% by weight of
Other monomers B ₂ with ethylenic double bonds,
Polymerized with at least one member selected from the group consisting of polyfunctional monomer B ₃ and graft cross-agent B ₄ and having a glass transition point Tg of 0° C. or lower,
(c) 50 to 100% by weight of fluorinated alkyl methacrylate C ₁ and 0 to 50% by weight of an ethylenic double bond. (d) 50 to 100% by weight of the outermost polymer layer C having a glass transition point Tg of 50° C. or higher by polymerizing the monomer C ₂ of 19 to 93 parts by weight; at least one member selected from the group consisting of fluorinated alkyl acrylate and fluorinated alkyl methacrylate, and ₀ to 50
% by weight of at least one member selected from the group consisting of another monomer D ₂ having an ethylenic double bond and a grafting agent D ₃ to obtain a glass transition point of the rubber elastic polymer layer B. Tg higher than the glass transition point Tg of the outermost polymer layer C
forming an intermediate polymer layer D of 1 to 75 parts by weight having a lower glass transition temperature Tg; and (e) 50 to 100% by weight of a fluorinated alkyl acrylate and a fluorinated alkyl methacrylate. Polymerizing at least one selected member _E1 ,
lower than the glass transition point Tg of the innermost polymer layer A;
forming a second intermediate polymer layer E of 1 to 75 parts by weight having a glass transition point Tg higher than the glass transition point Tg of the rubber elastic polymer layer B; Forming step (a) of combined layer A,
Forming step (e) of second intermediate polymer layer E, forming step (b) of rubber elastic polymer layer B, forming step of intermediate polymer layer D
(d), and the formation step (c) of the outermost polymer layer C, and the polymerization operations in each of steps (e), (b), (d), and (c) are performed before the polymerization step (c). carried out in the presence of the polymer formed by the steps, whereby the polymer layer of each step is formed outside the polymer layer obtained by the preceding step, and the ethylenic double bonds are removed. Monomers with (A ₂ ,
B ₂ , C ₂ and D ₂ ) are lower alkyl (meth)acrylate, lower alkoxy (meth)acrylate, cyanoethyl (meth)acrylate, acrylamide, acrylic acid, methacrylic acid, styrene, alkyl-substituted styrene, acrylonitrile and methacrylate. The polyfunctional monomer (A ₃ and B ₃ ) having an ethylenic double bond is selected from the group consisting of nitriles, ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene selected from the group consisting of glycol dimethacrylate, propylene glycol dimethacrylate, divinylbenzene, trivinylbenzene and alkylene glycol diacrylate, and said grafting cross-agent (A ₄ , B ₄ and D ₃ )
It is characterized in that it is selected from the group consisting of allyl, methallyl and crotyl esters of α-, β-unsaturated carboxylic acids and dicarboxylic acids, triallyl cyanurate and triallyl isocyanurate. Description of the invention In the method for producing a fluorinated acrylic multi-stage copolymer resin of the present invention, the polymer constituting the innermost polymer layer A contains fluorinated alkyl methacrylate A ₁ as a main component, and if desired, fluorinated alkyl methacrylate A 1 is used as a main component. methacrylate A ₁ , a monomer A ₂ having an ethylenic double bond copolymerizable with it, a polyfunctional monomer A ₃ ,
It is obtained by copolymerizing at least one selected from the group consisting of and graft cross-agent _A4 . The innermost polymer layer A must contain 50 to 100% by weight of fluorinated alkyl methacrylate A ₁ as a polymerization component. The rubber elastic polymer layer B, which forms a double structure together with the innermost polymer layer A, has a fluorinated alkyl acrylate and/or a fluorinated alkyl methacrylate B ₁ as a main polymer component, and has a glass transition temperature Tg of 0°C or lower. It has the following. In this rubber elastic polymer layer B, the fluorinated alkyl acrylate and/or the fluorinated alkyl methacrylate B ₁ may optionally contain a monomer B ₂ having an ethylenic double bond copolymerizable therewith, a polyfunctional It is obtained by copolymerizing with at least one member selected from the group consisting of monomer B ₃ or graft cross-agent B ₄ . It is necessary that the rubber elastic polymer layer B contains 50 to 100% by weight of fluorinated alkyl acrylate and/or fluorinated alkyl methacrylate _B1 as a polymerization component. The outermost polymer layer C has fluorinated alkyl methacrylate C ₁ as the main polymerization component, and
Tg is 50℃ or higher. This fluorinated alkyl methacrylate C ₁ is obtained by copolymerizing with another monomer C ₂ having an ethylenic double bond that can be copolymerized with it, if necessary. The outermost polymer layer C contains 50% fluorinated alkyl methacrylate _C1 as a polymerization component.
~100% by weight is required. The intermediate polymer layer D contains 50 to 100% by weight of fluorinated alkyl acrylate and/or fluorinated alkyl methacrylate _D1 as a main polymer component, and
If necessary, 0 to 50% by weight of other copolymerizable ethylenic double bond monomers D ₂
It is obtained by copolymerizing with at least one selected from _the group consisting of The intermediate polymer layer D is composed of one layer or two or more layers made of the above polymer, and each Tg is higher than that of the rubber elastic polymer layer B, and the Tg of the outermost polymer layer C is higher than that of the rubber elastic polymer layer B. Needs to be lower. That is,
The following relationship holds: Tg of rubber elastic polymer layer B < Tg of intermediate polymer layer D < Tg of outermost polymer layer C, and Tg increases monotonically in the direction of layer B → layer D → layer C. It is necessary. Between the innermost polymer layer A and the rubber elastic polymer layer B, at least one layer consisting of a fluorinated alkyl methacrylate and/or a copolymer containing fluorinated alkyl acrylate as a main component is formed. Second
An intermediate layer E may also be formed. In this case the second
The Tg of the intermediate layer E is lower than the Tg of the innermost polymer layer A and higher than the Tg of the rubber elastic polymer layer B. Therefore, the Tg is as follows: layer A → second intermediate layer E → layer B. It is preferable to decrease monotonically in the direction. Moreover, in order to form a graft between each of the layers A to E, it is preferable to copolymerize a graft cross-agent in each layer. In each of the above polymer layers A to E, the monomer component copolymerized with the main polymerization component is effective for adjusting the Tg value of each layer, but it reduces the processability of the resulting resin. This is not always necessary, as it can sometimes cause In addition, in the innermost polymer layer A and the rubber elastic polymer layer B, the polyfunctional monomers A ₃ and B ₃ used as copolymerization components form a crosslinked rubber elastic polymer, and the resulting multistage polymer layer This has the effect of improving the rubber elasticity and extensibility of the combined resin. When a graft reaction between the innermost polymer layer A and rubber elastic polymer layer B having rubber elasticity as described above and the intermediate layer D and outermost polymer layer C is required, each of these layers is formed. Sometimes grafting cross-agents can be used. In this way, a multistage polymer resin having good rubber elasticity as well as good transparency and extensibility can be obtained. The innermost polymer layer A contains a graft cross-agent component _A4 , and the rubber elastic polymer layer B contains a polyfunctional monomer component.
B ₃ and graft cross agent B ₄ , and when the intermediate polymer layer D contains the graft cross agent component D ₃ , the obtained multistage polymer resin has high elongation, due to its rubber elasticity effect and graft effect. It has good transparency and film formability, and does not cause whitening when folded. In order to obtain a multistage polymer resin with good rubber elasticity, it is necessary that the Tg of the rubber elastic polymer layer B is 0° C. or less. If the Tg of layer B is higher than 0°C, the obtained multistage polymer resin will not exhibit rubber elasticity at room temperature. Furthermore, in order to obtain a multistage polymer resin with excellent mechanical properties, it is necessary that the outermost polymer layer C has a Tg of 50° C. or higher. When the Tg of the C layer is lower than 50° C., the processing properties of the resulting multistage polymer resin, such as film moldability, extrusion moldability, and injection moldability, become unsatisfactory. In the multistage polymer resin of the present invention, the composition weight ratio of each layer is: Innermost polymer layer A: 1 to 25 parts, more preferably 5 parts
~15 parts Rubber elastic polymer layer B: 5 to 75 parts, more preferably
10 to 50 parts Outermost polymer layer C: 19 to 93 parts, more preferably 35 parts
-80 parts Intermediate polymer layer D: 1-75 parts, more preferably 5-75 parts
50 parts Second intermediate polymer layer E: 1 to 75 parts, more preferably 5 to 50 parts. In the method of the present invention, if the content of the innermost polymer layer A is less than 1 part by weight, the film processability and resistance to whitening on bending of the film will be unsatisfactory, and if the content is more than 25 parts by weight, , which is undesirable because it reduces film processability. The higher the Tg of the innermost polymer layer A, the better the moldability of the obtained multi-stage polymer resin film, and the higher the resistance to whitening when the film is folded. Further, if the Tg of the layer A is low, for example, approximately equal to the Tg of the rubber elastic polymer layer B, the resulting resin will have unsatisfactory film formability and resistance to film folding and whitening. If the content of the rubber elastic polymer layer B is less than 5 parts by weight, high elongation cannot be obtained, and if it is more than 75 parts by weight, the resin processability becomes unsatisfactory. If the content of layer B is 5 parts by weight or more and is relatively small compared to the content of outermost polymer layer C, even if the Tg of outermost polymer layer C is higher than 50 ° C. ,
Even when the temperature is close to 50°C, the processability and elongation of the obtained multistage polymer resin are good. In addition, when the content of layer B is 75 parts by weight or less and is relatively high compared to the content of layer C, the processability and elongation of the resulting multistage polymer resin are 50 parts by weight or less.
The higher the Tg above °C, the better the performance tends to be. If the content of the intermediate polymer layer D is less than 1 part by weight, the resulting multi-stage polymer resin will have insufficient resistance to whitening on film bending;
When the amount exceeds the weight part, high elongation cannot be obtained due to the relatively small amount of the rubber elastic layer B, and good processability cannot be obtained due to the relatively small amount of the outermost layer polymer C. Generally, as the content of the intermediate polymer layer D increases within the range of 1 to 75 parts by weight, the resistance of the resulting resin to film folding and whitening improves. In the method of the present invention, the main polymeric components of the innermost polymer layer A, the rubber elastic polymer layer B, the intermediate polymer layer D, the outermost polymer layer C, and optionally the second intermediate layer E of the multistage polymer resin The polyfluorinated alkyl acrylate and polyfluorinated alkyl methacrylate that constitute the formula have the following structural formula () or (). K0035 or K0036 However, in the above formula, m represents an integer of 1 to 5, n represents an integer of 1 to 10, X represents F or H atom, and Z represents H atom or -CH ₃ group. . Examples of the above-mentioned fluorinated alkyl acrylate polymers or fluorinated alkyl methacrylates include:
2,2-difluoroethyl-methacrylate (2FM) and -acrylate (2FA), 2,2,
2-trifluoroethyl-methacrylate (3FM) and -acrylate (3FA), 2,2,
3,3-tetrafluoropropyl-methacrylate (4FM) and -acrylate (4FA), 2,
2,3,3,3-pentafluoropropyl-methacrylate (5FM) and -acrylate (5FA), 2,2,3,3,4,4-hexafluorobutyl-methacrylate (6FM) and -acrylate (6FA), 2, 2, 3, 3, 4, 4,
5,5-octafluoropentyl-methacrylate (8FM) and -acrylate (8FA), 1,
1-di(trifluoromethyl)-2,2,2-trifluoroethyl-methacrylate (9FM) and -acrylate (9FA), 2,2,3,3,
4,4,5,5,6,6,7,7-dodecafluoropentyl-methacrylate (12FM) and -
Acrylate (12FA), 3, 3, 4, 4, 5,
5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10,
Examples include 10-heptadecafluorodecanyl methacrylate (17FM) and -acrylate (17FA). Generally, the fluorinated alkyl acrylate or fluorinated alkyl methacrylate used in the rubber elastic polymer layer B may have either a linear or branched side chain, but the resulting polymer A lower Tg is preferable. The ethylenic double bond-containing monomers (A ₂ , B ₂ , C ₂ , D ₂ ) copolymerizable with the above-mentioned fluorinated alkyl acrylate and/or fluorinated alkyl methacrylate include lower alkyl (meth)acrylate, lower Acrylic monomers such as alkoxy (meth)acrylate, cyanoethyl (meth)acrylate, acrylamide, acrylic acid, and methacrylic acid are preferred. Furthermore, styrene, alkyl-substituted styrene, acrylonitrile, methacrylonitrile, etc. can also be used. Such a copolymer component is effective in adjusting the Tg of the resulting polymer, but it also changes the refractive index of the polymer, so its content should be kept at 30% or less based on the total amount of the polymer, and should be kept as low as possible. Less is preferable. In addition, examples of polyfunctional monomers (A ₃ , B ₃ ) copolymerizable with fluorinated alkyl acrylate and/or fluorinated alkyl methacrylate include ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1, Alkylene glycol dimethacrylates such as 4-butylene glycol dimethacrylate and propylene glycol dimethacrylate are preferred, and divinylbenzene, trivinylbenzene, alkylene glycol diacrylate and the like can also be used.
These polyfunctional monomers are effective in crosslinking the polymer in which they are contained, but are not effective in interlayer crosslinking with other layers. Even if no polyfunctional monomer is used, if a grafting agent is used, cross-linking between layers is formed, and a multi-stage polymer resin with excellent safety can be obtained. However, although polyfunctional monomers are effectively used when the resulting resin is required to have excellent hot strength elongation, the amount used is preferably 10 parts by weight or less. Furthermore, as the grafting agent used with fluorinated alkyl acrylate and/or fluorinated alkyl methacrylate, copolymerizable α-, β-
- allyl of unsaturated carboxylic or dicarboxylic acids,
Methallyl or crotyl esters are used, preferably acrylic acid, methacrylic acid, maleic acid,
and allyl esters of fumaric acid are used, with allyl methacrylate being particularly effective. Other effective examples include triallyl cyanurate and triallyl isocyanurate. Such graft cross-agents mainly have conjugated unsaturated bonds in their ester structures that bond with allyl groups, methallyl groups, or crotyl groups of other polymer components, and a substantial portion of the conjugated unsaturated bonds in the ester structure of It effectively bonds with the above-mentioned group in the union and provides a graft bond between two adjacent layers. The amount of grafting agent used is important for adjusting the properties of the resulting resin, and
It is preferably used in a range of 10 parts by weight or less, and more preferably in a range of 0.01 to 5 parts, based on the intermediate polymer layer D. The multistage polymer resin of the present invention is produced by the following method. First, the innermost layer polymer A is produced by polymerizing predetermined monomer components in the presence of a catalyst at a temperature of 30° C. to 100° C. for 5 to 120 minutes. This polymerization may be carried out by any polymerization method, but it is generally preferable to use an emulsion polymerization method. As a catalyst, cumene hydroperoxide (CHP), di-tert-butyl peroxide, dicumyl peroxide, methyl ethyl ketone peroxide, tert-butyl perphthalate, tert-butyl perbenzoate, methyl isobutyl ketone peroxide, lauroyl peroxide, cyclohexyl peroxide, 2,
Organic peroxides such as 5-dimethyl- or 2,5-tert-butyl-peroxyhexane, tert-butyl peroctanoate, tert-butyl perisobutyrate, tert-butyl peroxyisopropyl carbonate, and methyl 2,2 '-Azobisisobutyrate, 1,1'-azobiscyclohexanecarbonitrile, 2-phenylazo-2,4-dimethyl 4-methoxyvaleronitrile, 2-carbamoylazobisisobutyronitrile, 2,2'-azobis Azo compounds such as (2,4-dimethylvaleronitrile) and 2,2'-azobisisobutyronitrile can be used, and the amount used is relative to the amount of monomer.
It is preferably used in a range of 0.01% to 5% by weight. Next, in the presence of the innermost polymer layer A, predetermined monomers and catalysts are polymerized at a temperature of 30° C. to 100° C. for 5 to 120 minutes. This polymerization operation also
Although any polymerization method may be used, it is generally preferable to use an emulsion polymerization method. The type and amount of catalyst used are the same as in the case of polymerization of the innermost layer polymer. Next, a predetermined monomer is polymerized in the presence of a catalyst in the presence of the innermost layer polymer-rubber elastic polymer double structure polymer to form an intermediate polymer layer on the outside of the rubber elastic polymer. do. The polymerization method, polymerization conditions, and catalyst at this time can be selected from the conditions and catalysts described above. Further, in the presence of the triple structure polymer obtained in the above step, a predetermined monomer is polymerized in the presence of a catalyst to form an outermost polymer layer. The polymerization method, conditions and catalyst at this time can be selected from those mentioned above. The resulting multistage polymer resin can be isolated, washed, and dried to obtain a powdered resin. The fluorinated acrylic multi-stage polymer resin obtained by the method of the present invention can be used by mixing with other thermoplastic resins, if necessary, and can also be used with other additives, such as oxidized It may be mixed with inhibitors, ultraviolet absorbers, fillers, pigments, antistatic agents, etc. The fluorinated acrylic multi-stage polymer resin of the present invention is used to form weather-resistant films, and is also useful as a sheath material for plastic or quartz-based optical fibers. The present invention will be further explained below with reference to Examples. In the examples, "parts" and "%" are by weight unless otherwise specified. In addition, the Tg of each polymer used in the examples is described in, for example, Polymer Handbook (published by John Willey & Sons).
It was calculated from the Tg value using the commonly known Fox formula: 1/Tg = a ₁ /Tg ₁ +a ₂ /Tg ₂ (a ₁ and a ₂ are weight fractions, respectively). In addition, if the Tg of the polymer is unknown, the PSC (differential thermal measurement) of the polymer
The Tg was determined from the measured value. The total light transmittance is
Measurement was performed using an integrating sphere haze meter in accordance with ASTMD-1003-61. Tear strength is JIS-P-
Measurement was performed using the Elmendorf method with a cut depth of 2 mm in accordance with 8116. The resistance to whitening on bending of the film sheet was expressed as follows based on the whitening state when the film sheet was bent by 180°. ◎...No whitening at all. 〇…Extremely slight whitening. △...Whitening is observed. ×... Severe whitening. ××...Severe whitening and breakage. For the contact angle, the advancing contact angle θ with respect to water was determined, and water repellency was evaluated based on this. (A Kyowa Kundak tangle meter CA-P type was used.) Processability was determined by using a 25 mmφ extruder to make a 100 mm wide T-
The film forming processability by die was evaluated. ×...Poor △...Medium 〇...Good The refractive index was measured by molding into a film of about 50 μm and using an Atsube refractometer. Example 1 250 parts of ion-exchanged water in a polymerization vessel with a cooler,
1 part of perfluoroalkyl sulfonate (Megafac F-110, manufactured by Dainippon Ink Chemical) and 0.05 part of sodium formaldehyde sulfoxylate were charged, and after stirring at room temperature in a nitrogen atmosphere, 2, 4 parts of 2,2 trifluoroethyl methacrylate (3FM), 1 part of methyl methacrylate (MMA), 0.25 part of 1,3-butylene dimethacrylate (BD), 0.05 part of allyl methacrylate (AMA), and cumene hydroperoxide (CHP) A mixture consisting of 0.05 parts was added and mixed. This mixture was heated to 70° C. and maintained at this temperature for 60 minutes to complete polymerization of the innermost layer polymer A.
Subsequently, 25 parts of 2,2,2-trifluoroethyl acrylate (3FA),
1,3-butylene dimethacrylate (BD) 2.5
0.7 parts of allyl methacrylate, and 0.25 parts of cumene hydroperoxide (CHP) were added dropwise over a period of 60 minutes, and the resulting mixture was kept at a temperature of 70°C for 60 minutes with stirring to obtain a rubber elastic weight. Polymerization of Coalesce B was completed. Further, in the resulting polymerization mixture, 5 parts of 2,2,2-trifluoroethyl acrylate (3FA), 5 parts of 2,2,2-trifluoroethyl methacrylate (3FM),
A mixture of 0.1 part of allyl methacrylate (AMA) and 0.1 part of cumene hydroperoxide (CHP) was added.
The mixture was added dropwise over 30 minutes, and the mixture was maintained at a temperature of 70° C. for 60 minutes while stirring to complete the polymerization of intermediate polymer D. Further, the resulting polymerization mixture contained 40 parts of 2,2,2-trifluoroethyl methacrylate (3FM), 20 parts of methyl methacrylate (MMA), and 0.5 parts of n-octyl mercaptan.
part, and cumene hydroperoxide (CHP)
A mixture of 0.5 parts was added dropwise over 60 minutes.
This mixture was maintained at a temperature of 70° C. for 60 minutes while stirring to complete polymerization of the outermost layer polymer. The obtained multistage polymer was in the state of a water-dispersed latex, and the polymerization conversion rate was 99%. The latex particle size was 950 angstroms. Multistage polymer emulsion obtained in this way
The multistage polymer resin was salted out by mixing 5 parts of calcium chloride to 100 parts, washed, dried, and subjected to extrusion molding. The residual amount of calcium in the final multistage polymer resin composition was 230 ppm. This dry powder of multi-stage polymer resin is processed into pellets using a 25 mm extrusion molding machine, and then the pellets are made into pellets with a width of 100 mm.
The film was formed using a T-die. As a result, this multistage polymer resin showed good film processability, and a film with a thickness of 50 μm was obtained that was highly transparent and flexible. The refractive index of this film is 1.4213
(Measured by 25℃ NaD ray 589.3nm Atsube refractometer)
The advancing contact angle with water was 76°. Also,
The resulting film had good resistance to whitening upon folding, and no whitening was observed. When measuring the viscoelastic behavior of this film, we found that E″ (dyne/
cm ² ) The peak of the loss modulus showed a gentle dispersion in the range of 25 to 80°C, and the tan δ showed a peak at a temperature of 83°C. Further, the obtained film had a total light transmittance of 92% and a haze of 2%, showing good transparency. Moreover, the tensile elongation at break of the obtained film was 30%. The composition of the multistage polymer resin of this example and the Tg of each component polymer layer are shown in Table 1, the amounts of the crosslinking monomer and grafting agent used are shown in Table 2, and the test results are shown in Table 3. Shown below. Examples 2-8 In each of Examples 2-8, the same operations as in Example 1 were carried out. However, the composition of each component polymer is as shown in Table 1, the amount of crosslinking monomer and grafting agent used is as shown in Table 2, and the test results are as shown in Table 3. It was as shown in. Comparative Example 1 The same operation as described in Example 1 was performed. However, the composition of each component polymer was as shown in Table 1, and the amounts of the crosslinking monomer and grafting agent used were as shown in Table 2. That is, in rubber elastic polymer B, 3FM is used instead of 3FA,
Its Tg is set to 0°C or higher, and 3FA is used instead of 3FM/MMA in the outermost layer polymer C.
Tg was set to 0°C or lower. The test results are shown in Table 3. That is, the film formability of the obtained multistage polymer resin is poor;
The obtained film easily whitened upon bending. Comparative Example 2 The same operation as in Example 1 was performed. However, the innermost layer polymer manufacturing operation was omitted, the composition of each component polymer was as shown in Table 1, and the amounts of crosslinking monomer and grafting agent were as shown in Table 2. It was hot. The obtained multi-stage polymer resin film easily whitened upon bending. Other test results were as shown in Table 3. Comparative Example 3 The same operation as in Example 1 was performed. However, the composition of each component polymer is as shown in Table 1, the manufacturing operation of the outermost layer polymer is omitted, and the amounts of crosslinking monomer and grafting agent used are as shown in Table 1. It was as shown in the table. The test results are shown in Table 3, but the film moldability of the obtained multi-stage polymer resin was so poor that no film to be used in the test could be obtained.

【table】

【table】

[Table] Effects of the Invention The fluorinated acrylic multi-stage polymer resin having a specific composition obtained by the method of the present invention not only has satisfactory light transmittance, haze, and refractive index, but also has excellent elongation at break. It is extremely useful as a weather-resistant film and an optical fiber sheath material because it has resistance to whitening upon film bending, and weather resistance.

Claims (1)

[Claims] 1. The following steps: (a) 50 to 100% by weight of fluorinated alkyl methacrylate (A ₁ ) and 0 to 50% by weight of
Other monomers A ₂ with ethylenic double bonds,
(b) forming an innermost polymer layer A of 1 to 25 parts by weight by polymerizing the polyfunctional monomer A ₃ and at least one member selected from the group consisting of the grafting agent A ₄ ; 50-100% by weight of at least one member _B1 selected from fluorinated alkyl acrylates and fluorinated alkyl methacrylates; 0-50% by weight of
Other monomers B ₂ with ethylenic double bonds,
Polymerized with at least one member selected from the group consisting of polyfunctional monomer B ₃ and graft cross-agent B ₄ and having a glass transition point Tg of 0° C. or lower,
(c) 50-100% by weight of fluorinated alkyl methacrylate C ₁ and 0-50% by weight of other ethylenic double bonds. a step of polymerizing monomer C ₂ to form an outermost polymer layer C having a glass transition point Tg of 50° C. or higher and having an amount of 19 to 93 parts by weight; and (d) 50 to 100% by weight of at least one member selected from the group consisting of fluorinated alkyl acrylate and fluorinated alkyl methacrylate, and ₀ to 50
% by weight of at least one member selected from the group consisting of another monomer D ₂ having an ethylenic double bond and a grafting agent D ₃ to obtain a glass transition point of the rubber elastic polymer layer B. Tg higher than the glass transition point Tg of the outermost polymer layer C
forming an intermediate polymer layer D of 1 to 75 parts by weight having a lower glass transition point Tg;
Step (b) of forming the rubber elastic polymer layer B, step (d) of forming the intermediate polymer layer D, and step (c) of forming the outermost polymer layer C, and step (b) , (d) and
The polymerization operations in each of (c) are carried out in the presence of the polymer formed by its preceding step, such that the polymer layer of each step is the same as the polymer layer obtained by its preceding step. A monomer (A ₂ ,
B ₂ , C ₂ and D ₂ ) are lower alkyl (meth)acrylate, lower alkoxy (meth)acrylate, cyanoethyl (meth)acrylate, acrylamide, acrylic acid, methacrylic acid, styrene, alkyl-substituted styrene, acrylonitrile and methacrylate. The polyfunctional monomer (A ₃ and B ₃ ) having an ethylenic double bond is selected from the group consisting of nitriles, ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene selected from the group consisting of glycol dimethacrylate, propylene glycol dimethacrylate, divinylbenzene, trivinylbenzene and alkylene glycol diacrylate, and said grafting cross-agent (A ₄ , B ₄ and D ₃ )
Fluorinated acrylic multistage polymer resin, characterized in that it is selected from the group consisting of allyl, methallyl, and crotyl esters of α-, β-unsaturated carboxylic acids, and dicarboxylic acids, triallyl cyanurate, and triallyl isocyanurate. manufacturing method. 2 The glass transition point Tg of the innermost combined layer A is
2. The method according to claim 1, wherein the rubber elastic polymer layer B has a glass transition point Tg higher than that of the rubber elastic polymer layer B. 3 Following steps: (a) 50 to 100% by weight of fluorinated alkyl methacrylate A ₁ and 0 to 50% by weight of other monomer A ₂ having an ethylenic double bond, polyfunctional monomer A ₃ and at least one member selected from the group consisting of graft cross-agent A ₄ to form an innermost polymer layer A of 1 to 25 parts by weight; (b) 50 to 100 parts by weight of at least one member _B1 selected from fluorinated alkyl acrylates and fluorinated alkyl methacrylates, and from 0 to 50% by weight of
Other monomers B ₂ with ethylenic double bonds,
Polymerized with at least one member selected from the group consisting of polyfunctional monomer B ₃ and graft cross-agent B ₄ and having a glass transition point Tg of 0° C. or lower,
(c) 50 to 100% by weight of fluorinated alkyl methacrylate C ₁ and 0 to 50% by weight of an ethylenic double bond. (d) 50 to 100% by weight of the outermost polymer layer C having a glass transition point Tg of 50° C. or higher by polymerizing the monomer C ₂ of 19 to 93 parts by weight; at least one member selected from the group consisting of fluorinated alkyl acrylate and fluorinated alkyl methacrylate, and ₀ to 50
% by weight of at least one member selected from the group consisting of another monomer D ₂ having an ethylenic double bond and a grafting agent D ₃ to obtain a glass transition point of the rubber elastic polymer layer B. higher than Tg, the glass transition point Tg of the outermost polymer layer C
forming an intermediate polymer layer D of 1 to 75 parts by weight having a lower glass transition temperature Tg; and (e) 50 to 100% by weight of a group consisting of fluorinated alkyl acrylates and fluorinated alkyl methacrylates. At least one _member selected from
1 to 75 with a glass transition temperature Tg higher than
forming a second intermediate polymer layer E in parts by weight, the step comprising forming an innermost polymer layer A (a);
Forming step (e) of second intermediate polymer layer E, forming step (b) of rubber elastic polymer layer B, forming step of intermediate polymer layer D
(d), and the formation step (c) of the outermost polymer layer C, and the polymerization operations in each of steps (e), (b), (d), and (c) are performed before the polymerization step (c). carried out in the presence of the polymer formed by the step, whereby the polymer layer of each step is formed outside the polymer layer obtained by the preceding step, and having said ethylenic double bond. Monomer (A ₂ ,
B ₂ , C ₂ and D ₂ ) are lower alkyl (meth)acrylate, lower alkoxy (meth)acrylate, cyanoethyl (meth)acrylate, acrylamide, acrylic acid, methacrylic acid, styrene, alkyl-substituted styrene, acrylonitrile and methacrylate. The polyfunctional monomer (A ₃ and B ₃ ) having an ethylenic double bond is selected from the group consisting of nitriles, ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene selected from the group consisting of glycol dimethacrylate, propylene glycol dimethacrylate, divinylbenzene, trivinylbenzene and alkylene glycol diacrylate, and said grafting cross-agent (A ₄ , B ₄ and D ₃ )
Fluorinated acrylic multistage polymer resin, characterized in that it is selected from the group consisting of allyl, methallyl, and crotyl esters of α-, β-unsaturated carboxylic acids, and dicarboxylic acids, triallyl cyanurate, and triallyl isocyanurate. manufacturing method.