FI57771C - VULKANISERBAR KLOROPRENPOLYMERBLANDNING - Google Patents

Description

ANNOUNCEMENT ___ „Λ ^ βΠ & · ® ^ UTLÄGGNINGSSKRIFT 5 77 7 1 C Patent granted 10 10 1030 uWP7 Batent meddelat. v (51) Kv-lkT / teta.3 0 08 L 11/00 FINLAND — FINLAND (21) p * »n« ih «k * mu · —PtMnen * ^ nf 3159/71 (22) H« k * m »* PiWt — Am6fcnlngfd« c 0l.ll.71 (23) AlkwpUvt — GlMgtiMsdag Oi. 11.71 (41) Tvllat (ulkMcsI - BfMt offemllg 06.05.72

Mntti. J. Registry Board NlhtMUp », moonUl.lk * un p ™ .-

Patani ocn reglsterstyrelsan AmMcm uthgd och utUkrtft ·· »pubiinrad 30.06.80 (32) (33) (31) PjT4« ttjr tuolkwe —a »gtrd prtorHet 05.11.70 USA (US) 87318 (71) Merck & Co., Inc. , 126 E. Lincoln Avenue, Rahway, New Jersey, USA ^ (72) Albert Jan Dalhuisen, Sunnyvale, California, William Henry Deis,

The present invention relates to a vulcanizable chloroprene polymer blend containing MgO dispersed in a weight of 5% of the dispersant present in the dispersant in the range of 5 to 70%. Belmont, California, USA (7l) Oy Kolster Ab (5l) per MgO, and containing (1) a rubber plasticizer to which metal soap may have been added, (2) a surfactant, or (3) a mixture of (1) and (2).

“Neoprene is a general term used for a group of synthetic elastomers based on polymers of chloroprene (2-chloro-1,3-butadiene). The group of neoprene blends generally comprises two classes, sulfur-modified (e.g., G-neoprene type) and non-sulfur-modified (e.g., W-neoprene type). It is to be understood that this invention is applicable to all types of chloroprene polymers prepared by polymerization, for example in the presence of mercaptans or other modifiers (chain transfer agents) such as dialkylxanthogen disulfides, or in the presence of sulfur followed by plasticization without further restriction. and subsequently removing the unchanged chloroprene monomer. All of these methods are described in more detail in the professional literature. See, for example, U.S. Patents 1,950 1 + 36, 2,227,517, 2,223-215 and 2,567,117. Neoprene GNA is an example of a G-type neoprene. This neoprene and its method of preparation are described in G.S. In the book "Synthetic Rubber" by Whitby *, pages 769-771, / John Wiley and Sons Inc. (195-17 · The chloroprene polymers used include mixtures prepared using both polychloroprene and the chloroprene polymer itself. the substances used as retarders, reinforcing agents, pigments and extenders are well known as well as the amounts to be used in different cases.

This knowledge is applicable to the present invention,

The use of MgO in the treatment of neoprene compounds is well known. The mechanism by which MgO benefits the vulcanization process is not fully understood, but its effect is briefly described in Whitby's book "Synthetic Rubber" (195k), pages 775-776 (John Wiley), which strikes a balance between processing reliability and curing rate when MgO is mixed with other oxides such as zinc oxide. The use of zinc oxide as the sole curing agent provides both rapid curing and a uniform curing state after extended vulcanization; i. such substances are "flat curing". Limitations of such compounds involve a significant tendency to prorchy or result in premature vulcanization of the system. In addition, the result is a leveling of the hardening at a relatively low point. The use of magnesium oxide as the sole curing agent produces neoprene compounds that are very slow curing and safe to handle, but tend to maintain curing activity. In addition, magnesium oxide improves the aging properties of the vulcanate, possibly by acting as a substance that binds the small amounts of hydrogen chloride released from neoprene during processing, curing and aging of the vulcanate. Together, zinc oxide and magnesium oxide complement each other, producing well-balanced materials whose properties can be varied, often to their advantage, by adjusting the ratio between these oxides. The vulcanizable chloroprene polymer composition according to the invention is characterized in that it contains 2 to 100 parts by weight of pentaerythritol per 100 parts by weight of MgO, the total amount of MgO, dispersant and pentaerythritol being 2 to 16 parts by weight per 100 parts by weight of polymer.

The use of a synergistic mixture of MgO and pentaerythritol results in improved Mooney pre-vulcanization protection and improved handling and storage safety for non-vulcanized neoprene. The synergistic mixture also does not adversely affect the properties of neoprene vulcanate. This results in less waste and greater freedom of action and greater flexibility in the handling and storage of unvulcanized neoprene.

MgO is commonly used to treat neoprene in both powder and dispersion form. The use of MgO dispersions containing pentaerythritol gives preparations with improved Mooney pre-vulcanization protection (in the original preparation and after aging) compared to the MgO preparations currently used in the rubber industry. MgO dispersions can be used in the treatment of neoprene in either liquid or solid form. The dispersions can be supplied to the neoprene manufacturers, for example in the form of pellets, sticks, lumps or spheres, etc., so that the dispersions can be suitably used in the treatment of neoprene. The relevant form of MgO dispersion is selectable and can be prepared by methods well known in the art.

^ It is well known in the industry that when exposed to atmospheric moisture and carbon dioxide, MgO is rapidly converted to carbonate or hydroxide. However, neither magnesium carbonate nor magnesium hydroxide is effective in vulcanizing neoprene in the same way that MgO is effective. Therefore, care must be taken to ensure that the MgO preparation intended for the treatment of neoprene does not suffer from loss of activity. Another advantage of the dispersions relates to their ability to retain MgO activity for remarkably long storage times without the use of precautions normally required in the industry.

The "neoprene grades" of MgO which have been precipitated and calcined after precipitation are used in the chloroprene mixtures according to the invention. In addition to these slightly calcined, highly surfactant forms of MgO, less active types of MgO can also be used. The group includes highly calcined types of MgO. The amount of pentaerythritol to be used is not critical and may range from about 2 to 100 parts by weight of pentaerythritol per 100 parts of MgO. The preferred range may range from about 5 to 25 parts per 100 parts of MgO. consist of any of the following: (1) a rubber plasticizer; (2) a surfactant; (3) a combination of a rubber plasticizer and a surfactant and / or metal soap. The amount of dispersing medium is not critical and may range from about 5 to 70 parts by weight of medium per 100 parts by weight of MgO. In the case where the dispersing medium consists of a mixture of rubber plasticizer and surfactant or metal soap, plasticizer and surfactant may k 57771 or the amount of metal soap will vary between 1% and 99% relative to the others. That is, a mixture of a plasticizer and a surfactant or metal soap may be used to form an effective dispersing medium, which mixture may be predominantly a rubber plasticizer or a predominant surfactant or metal soap, and all combinations are included in these values. It is a further object that the mixture of surfactant and metal soap can be used in combination with a rubber plasticizer, the ratio of surfactant to metal soap varying from 1 to 99% relative to each other. In the case where the dispersing medium contains a mixture of a surfactant and a metal soap in combination with a rubber plasticizer, the amount of the mixture relative to the rubber plasticizer is not critical and may vary from about 1 to 99% by weight of the rubber plasticizer.

The amount of MgO-pentaerythritol dispersant used to treat neoprene generally ranges from about 2 to 16 parts by weight per 100 parts of rubber. This includes systems in which a synergistic mixture of MgO and pentaerythritol is used as a treatment material both in the presence and absence of other metal oxides. For most applications, a recommended amount of k parts per 100 parts of rubber is recommended.

The quality of the pentaerythritol is not critical and any commercial source of pentaerythritol can be used in the practice of the invention. For example, the pure compound itself as well as a technical grade of pentaerythritol such as "Hercules PE-200" having the following properties are effective in the practice of the invention: "PE-200" monopentaerythritol content,% 88-2 hydroxyl content,% h-8 - 1 ash (NagSO 4),% 0.01 max, total solids,% 99.5 min, color, ASTM Pt-Co 35 max.

Fineness amount retained on the 200-mesh screen,% none amount retained on the 325-mesh screen,% 1.0 max.

The rubber plasticizer that can be used in the practice of this invention is not critical and includes plasticizers well known to those skilled in the art of rubber and commonly used for this purpose. In this regard, reference is made to Morton's book "Introduction to Rubber Technology, pp. 151-1T1» Reinhold Pub. Comp. (1961+); Murray and Thompson's publication "The Neoprenes", pp. 39 ~ ^ 1, Du Pont ( 1963), reference being made to the plasticizers disclosed therein, This chapter includes: 5 57771 rock oils, such as paraffinic, naphthenic and aromatic, resins, waxes and asphalt derived from rock oil are also included in this chapter;

Mineral oils are also included; esters such as esters of orgasmic alcohols and polybasic acids; resins and polymers such as aromatic hydrocarbon resins, polyisobutylene and polybutylene; oils, resins and resins obtained from pine trees, and coal tar. Natural fats and oils (edible oils, blown oils, fatty acids).

Typical examples of rock oils are, in particular, paraffinic rock oils, such as "Cyclolube® 2310" (Golden Bear Oil Co), naphthenic oils, such as "Shellflex®371" (Shell Chemical Company) and "Cyclolube® 138" (Golden Bear Oil Company) and aromatic oils such as "Bearflex®LPO" (Golden Bear Oil Company) and "Califlux® 550" (Golden Bear Oil Company). Examples of esters are butyl oleate, dibutyl phthalate and tricresyl phosphate, dioctyl sepacate, trioctyl phosphate and triethylene glycol caprylate. Typical resins and polymers are "Kenflex®N", "aromatic hydrocarbon" BRC®-22 "," Para-Flux 'and "Vistamex® LM-MH (non-coloring polyisobutylene having a molecular weight average molecular weight (Staudinger) of Typical edible oils that can be used with chloroprene polymers include linseed oil, rapeseed oil, and safflower oil.

Typical liner oils used as plasticizers have the following properties: "Shellflex ®371" viscosity, SSU / 37.8 ° C 420 SSU / 98.9 ° C 53.1 weight, ° API 26.1 specific gravity / 15 «5 ° C 0.8898 color, ASTM LO.5 flash point, C0C, ° C 215.6 casting temperature, ° C -31.7 volatility, 22 hours / 107.2 ° C weight-J? 0.62 Neutralization number mg KOH / g 0.03

Distillation, ° C

initial boiling point 376.7 5% 396.1 10% 402.8 50% 432.2 90% 462.8 6 57771 aniline point, ° C 98 »3 UV absorption capacity 2βθ ^ an 0.9 viscosity-weight constant 0, 81 + 0 refractive index / 20 ° C 1.1 + 890 refractive index 1.01 + 23 (Refractivity Intercept)

Molecular analysis, clay gel, weight # asphaltene hydrocarbons 0 polar compounds 0.3 aromatics 15.5 saturated substances 81 +, 2

Carbon atom analysis,% of aromatic carbon atoms, 2 naphthenic carbon atoms, C ^ 1 + 1 + paraffinic carbon atoms, Cp 51 * ASTM rubber extender oil type 1+ 7 57771 VO CO! C3 SC? ro -3-: cr): ct)

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Typical examples of metal soaps, i.e., fatty acid esters of metals, that are within the scope of the present invention include stearates of Ca, Al, Mg, and Fe, oleates, palmitates, and octoates. Other useful metals include Zn, Cd, Ba, Fb, Ha, K, Li and Ni. Preferred examples of metal soaps are Mg stearate, Ca stearate, Al stearate, Fe distearate and Fe tristearate.

Surfactants within the scope of this invention are either non-ionizable or ionizable or mixtures thereof. Descriptive groups of well-known materials include:

Non-ionizable substances mono- and diglycerides, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol esters, polyoxyethylene acids, fatty alcohols, propylene glycols, polyethylene glycols, polyethylene glycols, nonylphenoxypoly (ethyleneoxy) ethanols, the following poly (vinylpyrrolidone), such as "Ganex ®V" polymers, (h) modified low molecular weight polyethylene, (such as "Epolene®"). Ionizable substances Alkylarylsulfonates

It should be noted that the choice of surfactant is not critical to the practice of the invention insofar as it is either non-ionizable or ionizable and does not interfere with the vulcanization of neoprene.

Typical surfactants include:

Name of the substance Category

Non-ionizable substances "Span® ho", sorbitan monopalmitate Sorbitan fatty acid ester "Span® 80", "monooleate" Span® 85 "," trioleate "Tween 20", polyoxyethylene (20) Sorbitan monolaurate (Polyoxy-S) "Tween hO", " (20) "monopalmitate ethylene" Tween 60 "," (20) "monostearate λ sorbitan -" Tween ®80 "," (20) "monooleate (fatty acid N-esters 10 57771 (K)" Renexw20 ", fat and resin acids Polyoxyethylene acids Polyoxyethylene esters S) "Tergitol NPX" Nonylphenyl polyglycol ether

Name of the substance Category

Non-ionizable substances "Tergitol® 15-S-9" linear alcohol polyglycol ether (s) "Emulphor VN-1 + 30" polyoxyethylated fatty acid "Igepal ® CO-1 + 30" nonylphenoxypoly (ethyleneoxy) - ethanol glycerol monostearate glycerol monostearate glycerol monostearate glycerol "" cetylstearyl alcohol fatty alcohol "Carbowax ® 1 + 000" polyethylene glycol (S) "Epolene ^ E-11 +" modified low molecular weight polyethylene "Ganex ®V-216" modified poly (vinylpyrrolidone)

Ionizable substances "Atlas ® G3300" Alkylaryl sulfonate

As further examples of non-ionizable and ionizable substances that may be used in the practice of this invention, reference is made to publications such as "General Characteristics of Atlas Surfactants" (1963) and Detergents and Emulsifiers 1969 Annual, edited by John W. McCutcheon; reference is made herein to the non-ionizable substances disclosed therein.

Typical examples of combinations of surfactants with or without metal soaps are e.g. the following: (The preferred ratio of ingredients is given in brackets).

"Span ® 80" / "Tween ® 60" (50/50) "" / "Tween® 80" (60/1 + 0) "" / "" / ethylene glycol monostearate (25/25/50) "" / "" / glycerol monostearate (1 + 0/30/30) "" / "" / "Epolene®E-H +" (20/15/65) "" / "" / Ca stearate (1 + 0/30/30) " "/" "/" Carhowax® 1 + 000 "(UO / 30/30)" "/ Ca stearate (60/1 + 0)" "/ Al stearate (60/1 + 0)" Igepal ® C0- l + 30 "/ Ca stearate (67/33)" "" / Al stearate (67/33) 57771

Although the exact basis for the greatly improved results obtained with dispersions containing a synergistic mixture of MgO and pentaerythritol is not fully known, it is hypothesized that the preferred results may be due to the presence of MgO in pentaerythritol, which has a stabilizing effect on the polymer.

Pentaerythritol-containing dispersions of MgO can be prepared using methods well known in the art. According to one efficient method, MgO and pentaerythritol are dispersed in the dispersing medium with vigorous stirring. Mixing with a strong shear effect is desirable. The dispersion can be prepared at room temperature, but elevated temperatures (80 ° -120 ° C) are preferred. It should be noted that reducing the particle size of MgO (before, after or during the preparation of the dispersion) improves the efficiency of the dispersion.

All dispersions used in the following examples were prepared in a two-arm sigma-blade mixer. The mixer has an operating capacity of 2.6 liters and is equipped with a jacket for steam heating. Dispersions were prepared by adding all ingredients including pentaerythritol except MgO and stirring while heating to 100-105 ° C, then adding MgO and stirring at 100-105 ° C until the dispersing medium was completely moistened with MgO: n and pentaerythritol.

Neoprene precipitation was performed in a laboratory type 2-roll rubber rolling mill. The rubber rolling mill has a front roller and a rear roller, each with a diameter of 15.2 cm and a length of 33 cm. The front roller is rotated 2h rpm and the rear roller 33.6 rpm. A 5 »5 kW motor is used to operate the rolling mill. The composition of the neoprene rubber used in the following examples is as follows:

Neoprene rubber "Neoprene ® GNA" 100 parts of stearic acid 0.5

MgO powder or dispersion (with or without pentaerythritol) 4 SRF gas soot 29 "Neozone ^ A" (N-phenyl-N-naphthylamine, antioxidant) 2

ZnO 5 12 57771

The rubber is applied to the front roll of the laboratory rolling mill and the rolling mill is therefore operated until the strip is soft and non-porous. Stearic acid, MgO (powder or dispersion), gas soot, "Neozone ®A" and ZnO are added sequentially. Each substance is added evenly over the rollers and at a uniform rate and shaped into the mixture before the next material is added. After mixing, the mass is removed from the rolling mill, weighed and put back into the rolling mill. The rollers are placed at a distance of 0.76 mm from each other. The pulp is passed through a rolling mill 6 times. During rolling, water at a temperature of 20 ° C is passed through the rolls. The mass is then scraped off the rolling mill.

The scalding property of Mooney was determined on a Monsanto Mooney rheometer at 127 ° C using a small rotor according to ASTM Test Method No. D161 + 6-63.

The "Neoprene grade" MgO used in the following examples is "Maglite® D No. 3231", a lightly calcined, high surface activity magnesium oxide manufactured by Merck & Co, Inc. It has the following typical properties:

Chemical analysis typical value of magnesium oxide MgO 93.10% glow loss of 1 +, 86 carbon dioxide COg 0.1 + 6 bound water HgO 1 +, 1 + 0 calcium oxide CaO 0.79 silica SiOg 0.27 chloride Cl 0.17 sulphate SO ^ 0.68 iron oxide FegO ^ 0.03 alumina AlgO ^ 0.10 manganese Mn 0.0017 copper Cu 0.0002 acid insoluble matter 0.05

Physical analysis of a typical value

Appearance of a pure, white, odorless powder, refractive index 1.61+ specific gravity 3.32 kg kg / l 0.31+

O

loose weight (loose), kg / m 337 sieve analysis through a 100 mesh sieve 100% through a 200 mesh sieve 100% through a 325 mesh sieve 99.5% 13 _ 57771

Primary particle size determined by electron microscopy

Mean 0.086 microns distribution 0-0.05 p 20.9% 0.05-0.10 p U8.8 0.10-0.15 p 20.2 0.15-0.20 pi 7.1 0.20 -0.25 p 3.0 2 area 185 m / g iodine value 135

The dispersions were mixed with the neoprene rubber preparation described above using a laboratory rolling mill. They were used in U parts per 100 parts of rubber. For Ver (Ss), 4 parts per 100 parts of rubber were mixed using "Maglite® D" powder.

The effect of dispersions and additions of powders on the neoprene mixture was evaluated based on Mooney's pre-vulcanization times. t. ^ is the time required to increase the Mooney viscosity by 10 units above the minimum value, t ^ Q times for the initial Mooney pre-vulcanization property should be relatively long (similar to the result of using "Maglite®D" powder at 1 * parts / 100 parts). The unvulcanized mixtures were then aged for 6 days at 50 ° C, after which the Mooney viscosity was determined. If desired, the t ^ time should change slightly during storage aging. If the t 1 times of the original and stock-aged mixtures are short, the rubber processor will not have enough time to process and vulcanize its mixtures.

This results in waste. Relatively long t 1 times reduce waste losses and provide less critical conditions for the handling and storage of unvulcanized neo-prene mixtures.

Example I

This example compares the potency of a dispersion of MgO containing pentaerythritol (reagent grade) to the potency of a similar dispersion that does not contain this synergistic additive, using mineral oil as the dispersing medium. Dispersions of 1 * part per 100 parts of rubber were added to the neoprene.

57771 to

Dispersion composition Mooney pre-vulcanization protection time (weight- $) (in minutes) for original and stock-aged pulp "Maglite ®D" Pentaerythritol-Mineral- Original 6 days at 50 ° C _tool_oil_of_stored__50-50 3 * + 18 1 * 0 10 50 to 28

The results clearly show the beneficial synergistic effect of pentaerythritol.

Example II

In this example, dispersions are prepared in a dispersing medium consisting of naphthalene linseed oil, a surfactant (nonylphenoxypoly (ethyleneoxy) ethanol) and metal soap (calcium stearate). The effect obtained with or without the use of pentaerythritol (technical

Cb) quality), compared to "Maglite® D" powder. Dispersions and powder are used for each 1 »part per 100 parts neoprene: ... ,, ..

Mooney’s pre-vulcanization protection

Dispersion composition for t-jo-8 ^ ® · (in minutes) initial (weight-yf) derived and stocked mass "Maglite® D" Pentaerythritol- Oil Surface- Metal- Original 6 days at 50 ° C far active protection of storage 50- 1 + 5 3.5 1.5 to 25 1 + 7.5 2.5 1 + 5 3.5 1.5 to 30 1 + 5 5 1 * 5 3.5 1.5 to 30 to 10 1 + 5 3.5 1.5 to 32 (g) compared to "Maglite® D" powder 36 This example shows that the dispersions according to the invention give better performance than the powder and dispersion previously used.

Example III

In a similar manner, a dispersion can be prepared and evaluated using the following composition: "Maglite ® D" 50 wt.% Pentaerythritol 2.5 "surfactant 1 + 7.5" 5 5 7 7 71

Preparation of MgO Dispersion Containing Pentaerythritol in the Form of a Stick After the dispersion is prepared using high shear mixing, the hot dispersion is extruded through a hot die. The extruded rod is then cut into pieces of the desired length and cooled to room temperature.

Preparation of MgO Dispersion Containing Pentaerythritol into a Spherical Form Spheres are prepared by adding a hot dispersing medium to the powder while slowly stirring at about 100 ° C. The dispersing medium is added just enough to fuse the particles together.