FR2652815A1 - THERMOPLASTIC RESIN COMPOSITION HALOGEN CONTENT. - Google Patents

Abstract

This invention provides a halogen content thermoplastic resin composition comprising 100 parts by weight of a halogen content thermoplastic resin (A), 0.1 to 100 parts by weight of a moldable vinyl alcohol polymer. the molten state (B), and 0.1 to 300 parts by weight of a thermoplastic polyurethane resin (C).

Description

The present invention relates to a thermoplastic resin composition

  with halogen content, excellent with regard to workability, appearance, resistance, hydrophilicity, resistance to oils and solvents, and the property of

gas barrier.

  Not only are vinyl chloride polymers relatively inexpensive, but they also have high clarity and excellent mechanical properties,

  and they have therefore been used in a variety of applications.

  cations, such as films, sheets, flexible pipes, flexible containers, coated fabrics, artificial leathers, heavy fabric articles, shoe soles, sponges, sheathing of electric wires, household utensils, etc. Having the advantages mentioned above on the one hand, vinyl chloride polymers are disadvantageous on the other hand, by the fact that they are not satisfactory in the processability, the hydrophilic character, the resistance to oils and solvents, gas barrier property, and adhesion

to substrates.

  To improve the workability, hydrophilicity and other properties of vinyl chloride polymers, it has been practiced to mix these resins, by the technique of mechanical mixing of the polymers, with a modifier resin , such as a hydrolyzed ethylene-vinyl acetate copolymer. By way of example, Japanese patent application KOKAI no. 69 955/1977 describes a barrier packaging composition of poly (vinyl chloride), essentially comprising a mixture of a polymer of vinyl chloride and of an ethylene alcohol copolymer vinyl, the proportion of which is 10 to 30 percent by weight based

vinyl chloride polymer.

  Japanese patent application KOKAI No. 238 345/1985 describes a resin composition comprising: (a) a thermoplastic resin (comprising poly (vinyl chloride)); (b) an ethylene-hydrolyzed vinyl acetate copolymer; and (c) a salt or an oxide, containing at least one element chosen from the group consisting of the elements of Groups I, II and III of the Periodic Table of the Elements, and mentions that this composition has a

  remarkably improved compatibility.

  The publication of Japanese Patent No. 59-39,464

  describes a polymeric vinyl chloride alloy-

  polyurethane, which can be obtained by reacting a polyol with a polyisocyanate, in the presence of a vinyl chloride polymer. However, this document does not refer to a combination of such an alloy of polymers

  with a vinyl alcohol polymer.

  The incorporation of a hydrolyzed ethylene-vinyl acetate copolymer into a halogen-containing thermoplastic resin, such as a vinyl chloride polymer, leads to improvements in hydrophilicity, resistance to oils and solvents and the gas barrier property, the inherent poor compatibility of the two resins makes mass molding difficult, and, moreover, the products which can be obtained from them by melt molding

  have problems with foreign materials and discoloration

  ration, as well as poor mechanical properties.

  The composition in accordance with the patent application

  Japanese KOKAI n 238 345/1985, which is discussed above

  above, offers improved compatibility, but the degree of improvement by the addition of a salt or oxide has its own limit, and there is still much to be improved. The object of the present invention is to overcome the above mentioned problems of the technology of

  the prior art by additionally incorporating a poly-

  thermoplastic urethane, in the context of improving the characteristics of a thermoplastic resin with a content

  in halogen with a vinyl alcohol polymer.

  The present invention therefore relates to a thermoplastic composition with halogen content, characterized in that it comprises: - 100 parts by weight of a thermoplastic resin with halogen content (A); - 0.1 to 100 parts by weight of a vinyl alcohol polymer which can be molded in the molten state (B); and

  - 0.1 to 300 parts by weight of a poly resin

thermoplastic urethane (C).

  The present invention is described in more detail below. Thermoplastic resin with halogen content (A) As examples of thermoplastic resin with halogen content (A), there may be mentioned a poly (vinyl chloride) resin, a poly (vinylidene chloride resin), chlorinated polyethylene, chlorinated polypropylene, a vinyl acetate-chlorinated polyethylene copolymer and chlorosulfonated polyethylene. Particularly useful are poly (vinyl chloride) resins, namely a vinyl chloride homopolymer and copolymers of vinyl chloride with other comonomers. Polymer of vinyl alcohol (B) The polymer of vinyl alcohol (B) comprises, among other things, homopolymers and copolymers of vinyl alcohol which can be molded in the molten state, such as polyvinyl alcohols of relatively polymerization low, partially hydrolyzed polyvinyl acetates, post-modification products (acetalized, cetalized and cyanoetherated) of polyvinyl alcohols, and hydrolyzed copolymers of vinyl acetate with various monomers copolymerizable with it (e.g., olefins, such as ethylene, propylene, isobutene, a-octene, a-octadecene, etc., unsaturated carboxylic acids, or their salts, partial alkyl esters, alkyl esters, nitriles, amides or anhydrides, sulfonic acids unsaturated or their salts, vinyl esters other than vinyl acetate, etc.). However, it should be understood that the proportion of the monomer or monomers copolymerizable (s) with vinyl acetate must not be greater than 30 mole percent, except that, in the case of ethylene, its proportion does not must not exceed

per hundred moles.

  Among the polymers mentioned above, a hydrolyzed ethylene-vinyl acetate copolymer, having a degree of saponification of vinyl acetate (ethylene content: 20-75% by moles, preferably 25-60% by moles) which is not less than 50 mole percent (preferably not less than 70 mole percent) is most useful. The vinyl alcohol polymers lying outside the above copolymer composition are insufficient in their potential to improve the properties of the thermoplastic resin with halogen content (A). It should also be understood that, as long as the above-mentioned range of the copolymer composition is respected, the vinyl alcohol polymers (B) can contain other comonomers in minor proportions. Among these vinyl alcohol polymers (B), a vinyl alcohol polymer, with a low ash content and a low alkali metal content, having a melting point not exceeding 200 C and ash and alkali metal contents not exceeding certain limits, is

particularly useful.

  Since the halogen-containing thermoplastic resin (A) is generally molded at a temperature not exceeding 200 C, any vinyl alcohol polymer (B), having a melting point exceeding 200 C, will not completely dispersed in (A) and, therefore, the physical properties of the resulting product can

  not be completely satisfactory.

  In addition, if the ash content and / or the alkali metal content of (B) exceeds a certain limit, the halogen-containing thermoplastic resin is susceptible

  to undergo discoloration and decomposition.

  The hydrolyzed vinyl acetate copolymer can, in general, be prepared by hydrolysis (saponification) of a vinyl acetate copolymer using an alkaline catalyst. However, industrial water and generally used industrial reagents contain metal salts as impurities and the saponification catalyst (an alkali metal hydroxide) remains as alkali metal acetate after the reaction, with the result that such impurities and such alkali metal acetate tend to be contained in the saponified polymer separated by precipitation or filtration from the saponification reaction mixture. Although it depends on various factors, such as the comonomer content of the resin, the degree of saponification, the conditions of the saponification reaction, etc., the ash and alkali metal content of the hydrolyzed vinyl acetate copolymer thus obtained usually range from about 5,000 to

  50,000 ppm and approximately 4,000 to 40,000 ppm.

  In the manufacture of polyvinyl alcohol or a modification thereof, an acid or an alkali is used as the catalyst. When an acid is used as a catalyst, a metal hydroxide or carbonate is used in the neutralization step after the reaction. Therefore, a fairly good amount of

  alkali metal is inevitably contained.

  The expression "ash content" is used

  here to designate the value found as follows.

  The hydrolyzed vinyl acetate copolymer is dried, taken up in a platinum evaporation pan and charred by means of an electric heating device and a gas burner. The carbonized resin is then introduced into an electric oven maintained at 400 C. The temperature of the oven is then raised to 700 C, temperature at which it is completely reduced to ashes within 3 hours. The ashes are removed from the oven, allowed to cool for 5 minutes, then

  let them sit in a desiccator for 25 minutes.

  Finally, the ashes are weighed precisely.

  The term "alkali metal content" is used herein to denote the value found as follows. After the hydrolyzed vinyl acetate copolymer has been reduced to ash as in the determination of the ash content, the ash is dissolved in an aqueous solution of hydrogen chloride under heating and the solution is subjected to

  atomic absorption spectrometry.

  The hydrolyzed ethylene vinyl acetate copolymer to be used in accordance with the invention preferably has an ash content, as determined by the above procedure, not exceeding 300 ppm, more desirably not exceeding not 50 ppm, for even better results, not exceeding ppm, and an alkali metal content, also as determined by the procedure described above, not exceeding 200 ppm, more desirably not exceeding 35 ppm, and for even better results, not exceeding 5 ppm. The ash and alkali content is preferably as low

  as possible inside the respective ranges mention-

  born above, but due to various limitations on purification in industrial production, the practical lower limits are about 1 ppm for

  ash and about 0.5 ppm for alkali metals.

  The vinyl alcohol copolymer mentioned above

  top, low in ash and alkali metals, can be prepared as follows. The powders, granules or pellets of said vinyl alcohol copolymer are washed carefully with an acid, preferably a solution of a weak acid in water or an organic solvent, such as methanol, to remove the salts responsible for said ash. and said alkali metals, then they are preferably washed with water or an organic solvent, such as methanol, to remove resin

  absorbed acid, and they are dried.

  In this connection, the water to be used in the preparation of aqueous solutions or in the washing procedure is deionized water, and the same

  thing applies to the following description.

  As an example of the weak acid mentioned above

  above, we can mention acetic acid, propionic acid, glycolic acid, lactic acid, adipic acid, azelaic acid, glutaric acid, succinic acid, benzoic acid, isophthalic acid, terephthalic acid, etc. Generally speaking, a weak acid with a pKa value of not less than 3.5 at 25 C

is preferred.

  After treatment with a weak acid

  above and either before or after washing with water or an organic solvent, such as methanol, another treatment is preferably carried out with a dilute aqueous solution of strong acid, for example, an organic acid. having a pKa value not exceeding 2.5 to 25 C, such as oxalic acid, maleic acid, etc., or a mineral acid, such as phosphoric acid, sulfuric acid, acid nitric, hydrochloric acid, etc. By this treatment with a strong acid, the elimination of metals

  alkaline can be accomplished more effectively.

  Thermoplastic polyurethane resin (C) The thermoplastic polyurethane resin (C) is obtained by reacting a polyol with a polyisocyanate

as mentioned below.

  Among the urethane materials, the polyol includes polyester polyols (condensed polyester polyols, polyester polyols of the lactone type, polycarbonate

  diols, etc.) and polyether polyols.

  Among the condensed polyester polyols are the reaction products of dicarboxylic acids (such as adipic acid, succinic acid, azelaic acid, pimellic acid, sebacic acid, phthalic acid, etc. .) or their lower alkyl esters with linear aliphatic diols (such as ethylene glycol, butanediol-1,4, hexanediol-1,6, decamethylene glycol-1,10, etc.) or aliphatic diols having side chains (such as propylene

  glycol-1,2, butanediol-3, 2,5-dimethyl hexane-

  2,5-diol, 2,2-diethyl-1,3-propanediol, neopentyl

glycol, etc.).

  Among the lactone type polyester polyols are the reaction products of lactone type compounds (such as p-propionolactone, pivalolactone,

  6-valerolactone, a-caprolactone, methyl-a-capro-

  lactone, dimethyl-a-caprolactone, trimethyl-e-capro-

  lactone, etc.) with a hydroxylated compound, such as a polyol

short chain.

  Among the polycarbonate polyols are polyols obtained by transesterification from a hydroxylated compound, for example, a short chain polyol, and a diallyl carbonate, a dialkyl carbonate, an ethylene carbonate or the like. Thus, for example, polyhexamethylene carbonate-1,6, poly-bis (4-hydroxyhexyl) -2,2 'propane carbonate, etc., which are commercially available, can be used. Another process for preparing a polycarbonate polyol is the so-called process

  phosgene (or the solvent process).

  Among the polyether polyols are polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxypropylene glycol, glycerol-based polyalkylene ether glycol, etc. Besides the above polyols, various other polyols known for the manufacture of polyurethanes

can also be used.

  Regarding the relative advantage of a polyester polyol and a polyether polyol, the former is

more useful.

  Among the urethanization materials, the polyisocyanate comprises aliphatic or alicyclic diisocyanates, such as tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, cyclohexylmethane diisocyanate, trimethyl-2,2,4 or -2 , 4,4 hexamethylene diisocyanate, isopropylidene bis (4-cyclohexyl isocyanate), methyl cyclohexane diisocyanate, isophorone diisocyanate, etc., tolylene diisocyanate-2,4 or -2,6, diphenylmethane

  diisocyanate-4,4 ', 3-methyl diphenylmethane-diiso-

  cyanate-4,4 ', m- or p-phenylene diisocyanate,

  2,4-chlorophenylene diisocyanate, naphthalene diiso-

  cyanate-1,5, xylylene diisocyanate, tetramethyl-

  xylylene diisocyanate and adducts

  polyalcohol-polyisocyanate, among others.

  In the conduct of the urethanation reaction,

  a chain extender, such as poly- alcohol

  atomic, a polyamine or the like, can be used.

  Formulation The proportion of the vinyl alcohol polymer (B), based on 100 parts by weight of the halogen-containing thermoplastic resin (A), is chosen in the range of 0.1 to 100 parts by weight. The preferred range is 0.5 to 50 parts by weight. A defect in vinyl alcohol polymer (B) does not provide the effect of improving the characteristics of the thermoplastic resin with halogen content, while an excess of vinyl alcohol polymer (B) affects the properties resin

  thermoplastic with halogen content (A).

  The proportion of the thermoplastic polyurethane resin (C), based on 100 parts by weight of the halogen-containing thermoplastic resin (A), is chosen in the range of 0.1 to 300 parts by weight. The preferred range is 5 to 150 parts by weight. If the proportion of the thermoplastic polyurethane resin (C) is too low, the compatibility between the halogen-containing thermoplastic resin (A) and the vinyl alcohol polymer (B) will not be improved, so that the suitability molding and appearance, as well as properties

  of the molded articles will not be satisfactory.

  Furthermore, the use of excess thermoplastic polyurethane resin (C) affects the proper properties.

  halogen content thermoplastic resin (A).

  Other Additives The halogen-containing thermoplastic resin composition of this invention may comprise, in addition to the components described above, various additives which are conventionally used for poly (vinyl chloride) resin, such as plasticizers, antioxidants, stabilizers, auxiliary stabilizers, ultraviolet absorbers, dyes and pigments, fillers, lubricants, antistatic agents, surfactants, chelating agents, reinforcing materials, foaming agents, flame retardants, agents improving impact resistance, etc. In addition, unless the object and results of this invention are compromised, other types of resins

  thermoplastics can also be incorporated.

  Mixing order The halogen-containing thermoplastic resin (A), the vinyl alcohol polymer (B), the thermoplastic polyurethane resin (C) and the other additives can be mixed, either simultaneously or in a

  any order for molding in the molten state.

  Molten molding As melt molding techniques that can be used, any of the calendering molding, extrusion molding,

  injection and blow molding, can be used.

RESULTS PROVIDED BY THE INVENTION

  The addition of the thermoplastic polyurethane resin (C) to a molding composition consisting of thermoplastic resin containing halogen (A) and vinyl alcohol polymer (B) according to this invention leads to a marked improvement in the compatibility between (A) and (B), without hampering the improvement effect of (B)

on the properties of (A).

  Therefore, in calendering molding, the problem of adhesion of the molding composition to the "flat plate" metal roller is eliminated, while extrusion molding can be carried out continuously for mass production operation. In addition, discoloration of molded articles is effectively inhibited, and the appearance and physical properties of molded articles

  are improved remarkably.

EXAMPLES

  The following examples are still intended for

illustrate the present invention.

- Choice of Materials -

  As a halogen-containing thermoplastic resin (A), vinyl alcohol polymer (B) and thermoplastic polyurethane resin (C), the following materials

have been chosen.

  Thermoplastic resin with halogen content (A) (A-1) Poly (vinyl chloride) (degree of

polymerization: 1100).

  (A-2) Copolymer of vinylidene chloride-methyl methacrylate (methyl methacrylate: 7 mol%). Vinyl alcohol polymer (B) (B-1) Hydrolyzed ethylene vinyl acetate copolymer (ethylene content: 44 mol%, degree of saponification of vinyl acetate: 99.5 mol%, mp: 167 C, ash content: 6 ppm,

  metallic sodium content: 2.7 ppm).

  (B-2) Ethylene-vinyl hydrolyzed vinyl acetate copolymer (ethylene content: 55 mol%, degree of saponification of vinyl acetate: 79.0 mol%, mp: 111 C, ash content: 15 ppm ,

  metallic sodium content: 4.0 ppm).

  (B-3) Hydrolyzate of dodecene-l-vinyl acetate copolymer (dodecene-1 content: 5.5 mol%, degree of saponification of vinyl acetate: 99.3 mol%, mp: 187 C , ash content: 215 ppm, metallic sodium content:

ppm).

  (B-4) Polyvinyl alcohol (degree of polymerization: 500, degree of saponification: 70.0 mol%, m.p .: 170 C, ash content: 120 ppm,

  metallic sodium content: 70 ppm).

  Thermoplastic polyurethane resin (C) (C-1) A thermoplastic polyurethane obtained by reacting tolylene diisocyanate with a polyester polyol which has a molecular weight of 2000 and which can be obtained by condensation of adipic acid with butanediol-l, 4 /

  neopentyl glycol (mol ratio: 9/1).

  (C-2) A commercial thermoplastic polyurethane (Dainippon Ink and Chemicals, "Pandex T-5000 P,

polyester type urethane.

  (C-3) A commercial thermoplastic polyurethane (Dainippon Ink and Chemicals, "Pandex T-6085,

polyether type urethane.

  - Formulation and Molding Conditions -

  Using the above materials, in the proportions indicated in Table 1, a preliminary mixing was carried out, then the respective compositions were molded by extrusion under the conditions described below. In what follows, all parts are by weight.

  However, in the case where the thermosetting resin

  plastic with halogen content (A) was (A-1), the mixture formulation and the molding conditions were as follows: (Composition formulation) Poly (vinyl chloride) (A-1) ..... ...... 100 parts Vinyl alcohol polymer (B) .......... As indicated Thermoplastic polyurethane (C) ........ As indicated Stabilizer ...... ...............

  ....... 6.5 parts The composition of the stabilizer was as follows: Epoxidized soybean oil ................ 3.0 parts Ba-Zn stearate composite stabilizer ..................... 3.3 parts Stearoylbenzoylmethane ... DTD: ............. 0.2 parts (Conditions extrusion molding machine) Extruder: an extruder of 30 mm (diameter) T-die: 200 mm wide, sheet thickness of 0.3 mm Screw: worm screw with constant pitch, L / D = 20, ratio compression: 3.0, rotation speed: 300 rpm Temperature: Cl: 150 C, C2: 1750C, C3: 185 C..DTD: H: 170 C, D: 185 C

  Grid: 177 µm mesh opening (80 mesh) x 2 Receiving coil: 8590 C When the thermoplastic resin with halogen content (A) is (A-2), the formulation of the composition and the conditions of extrusion molding have been fixed as follows: (Formulation of the composition)

  Vinylidene chloride copolymer-

  methyl methacrylate (A-2) ............ 100 parts Vinyl alcohol polymer (B) ........... As indicated Thermoplastic polyurethane (C) ..

  .... As indicated Stabilizer .............................. 4.2 parts The composition of the stabilizer was as follows: Oil epoxidized soybeans ................ 3.0 parts Calcium stearate ................... 0.5 part Zinc stearate ...................... 0.5 part Stearoylbenzoylmethane ................ 0.2 part (Molding conditions) Extruder: an extruder of 40 mm (diameter) Screw: L / D = 23, compression ratio: 3.2; 300 rpm (The other conditions are the same as for..DTD: the extrusion process described above).

  The conditions and results are presented in

Table 1.

Table 1

  Product Properties Formulation

  composition Incident Appearance of the product Transmit- Resistance Half

  molding time 2-component shock / light N.cm/cm total parts discharge (%) (kg.cm/cm) (in sec.) A-1 100 Color: none> 588, 6 Example 1 B-1 30 No YP incidents: none 83 (> 60) 30 C-1 20 Streaks: none A-1 100 Coloring: none> 490.5 Example 2 B-2 40 No YP incidents: none 78 (> 50) 35 C-2 20 Streaks: none A-1 100 Coloring: none Example 3 B-3 30 No incidents YP: none 85 Not destroyed 45 C-3 50 Streaks: none A-1 100 Coloring: none Example 4 B- 1 10 No YP incidents: none 87 Not destroyed 50 C-1 50 Streaks: none A-1 100 Coloring: none> 490.5 Example 5 B-1 30 No YP incidents: none 81 (> 50) 25 C-3 10 Streaks: none A-1 100 Coloring: none> 539.55 Example 6 B-2 20 No incidents YP: none 82 (> 55) 30 C-3 10 Streaks: none A-1 100 Coloring: none Example 7 B-3 40 No incidents YP: none 87 Not destroyed 55 C-1 100 Streaks: none Table 1 (continued) Formulation Product properties of the

  composition Incident Appearance of the product Transmit- Resistance Half

  impact strength component / light time N.cm/cm2 total parts discharge (%) (kg.cm/cm2) (in sec.) A-1 100 Color: none Example 8 B-4 20 No incidents YP: none 88 Not destroyed 55 C-2 150 Streaks: none A-2 100 Coloring: none> 441.45 Example 9 B-1 40 No incidents YP: none 78 (> 45) 35 C-3 10 Streaks: none A-2 100 Coloring: none Example B-4 10 No incidents YP: none 88 Not destroyed 60 C-1 100 Streaks: none Example A-1 100 Burrs, mark Color: yellow 29.43 Compara- B-1 30 pouring, YP: multiples 55 (3) 180 tif 1 jerk Streaks: S Example A-1 100 Burrs, mark Color: yellow 29.43 Compara- B-3 30 pouring, YP: multiples 40 (3) 150 tif 2 roughly Streaks: S Example A-1 100 Burrs, mark Color: yellow 19.62 Compara- B-4 30 pouring, YP: multiples 35 (2) 100 tif 3 jerk Streaks: S Example A-2 100 Burrs, brand Color: yellow 19.62 Compara- B-1 30 pouring, YP: multiples 50 (2) 100 tif 4 jerk Streaks: S

  (NOTE): in the "Product appearance" column, "Streaks: S" means that there are streaks.

  Determination and evaluation have been done

as follows.

  Suitability for extrusion molding was assessed in terms of drop in water level, torque variation and other anomalies during 8 hours of molding

continuously.

  The appearance of the molded test pieces was evaluated after 8 hours of continuous molding in terms of discoloration, fish eyes (YP), streaks, etc. Total light transmittance has been measured

  in accordance with JIS K 6745 (sheet 1 mm thick).

  With regard to impact resistance, Izod impact resistance was measured in accordance with JIS K 7110. In the table, the expression "not destroyed"

  means that 10 specimens were invariably non-

  destroyed, and> 441.45 (> 45),> 490.5 (> 50),> 539.55 (> 55) and> 588.6 (> 60) mean that the minimum values for 10 specimens were 441 respectively , 45 (45), 490.5 (50),

539.55 (55) and 588.6 (60).

  The half-discharge time was measured using an "honest meter". With the halogen-containing thermoplastic resin (A) alone, the half-discharge time

  was for both (A-1) and (A-2).

Claims (4)

  1 - Composition of thermoplastic resin with halogen content, characterized in that it comprises: - 100 parts by weight of a thermoplastic resin with halogen content (A); - 0.1 to 100 parts by weight of a vinyl alcohol polymer which can be molded in the molten state (B); and   - 0.1 to 300 parts by weight of a poly resin thermoplastic urethane (C).   2 - Composition according to Claim 1, characterized in that the said vinyl alcohol polymer (B) is a vinyl alcohol polymer with a low content of alkali metals, with a low ash content, having a melting point not exceeding 200 C, an ash content not exceeding 300 ppm, and a content of   alkali metals not exceeding 200 ppm.   3 - Composition according to claim 1, characterized in that said vinyl alcohol polymer (B) is an ethylene-hydrolyzed vinyl acetate copolymer, having an ethylene content ranging from 20 to mole percent and a degree of saponification   vinyl acetate of not less than 50 mole percent.   4 - Composition according to claim 3,   characterized by the fact that said ethylene-   hydrolyzed vinyl acetate is an ethylene copolymer   vinyl acetate with low ash content, low alkali metal content, having a melting point not exceeding 200 C, an ash content not exceeding 300 ppm and an alkali metal content not exceeding ppm.