DE2644242A1 - METHOD FOR PRODUCING MOLECULAR WEIGHT CONTROLLED POLY (IMINOIMIDAZOLINDIONE) - Google Patents

Description

DR. BERG DiPL.-ING. STAPF DIPL.-ING. SCHWABE Dk. DR. SANDMAIR

8 MUNICH 86, POST BOX 86 02 45

Dr. Berg Dipl.-Ing. Stapf and Partner, 8 Munich 86, P. O. Box 86Q2 45

Your reference Our reference 8 MÜNCHEN 80 Q f) CTD 1Q7R

Yourref. Ourref. Mauerkircherstraße 45 O LF. W "

Lawyer File 27 443
Be / Ro

Exxon Research, and Engineering Company linden, Hew Jersey / U.S.A.

"Process for the production of molecular weight controlled

Poly (iminoimidazolidinediones) "

PolyCiminoimidazolidinediones) can be produced by that one reacts hydrogen cyanide with diisocyanates or dicyanoformamides with diisocyanates or a cyanoformamidyl isocyanate polymerized in a suitable solvent (US patents 3,591,562, 3,547,897, 3,635,905, 3,684,773).

Telegrams: BERGSTAPFPATENT Munich Banks: Bayerische Vereinsbank Munich 453100

TELEX: 0524560 BERG d Hypo-Bank Munich 3892623

Post check Munich 65343-808

7G9815 / 1Q6i

The products have molecular weights (140,000 - 300,000), higher than that required for many purposes and ease of use "in various manufacturing processes or is desired. Water, amines, etc. are examples of impurities that reduce molecular weight, but in an uncontrolled manner.

The present invention makes the molecular weights of the poly (iminoimidazolidinediones) ground during polymerization controlled by adding a critical and measured amount of a monoisocyanate to the reaction mixture introduces.

Poly (iminoimidazolidinediones) are made by that one reacts hydrogen cyanide with diisocyanates or dicyanoformamides with diisocyanates or cyanoformamidyl isocyanates polymerized. It was found and constitutes an essential part of this invention that the Degree of polymerization by the presence of a preselected, calculated, controlled amount of a monoisocyanate controlled in the polymerization solution in an effective manner can be.

Because the degree of polymerization is at a predetermined level is decreased by introducing a measured amount of a monoisocyanate into the polymerization solution the amount of monoisocyanate used to control the degree of polymerization must be used in a specific

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G-rade critical, and can be calculated as follows.

First, the polymerization conditions must be set. Then a polyiminoimidazolidinedione is exhibited the parts of the monomers and solvents used to prepare the polymer in the presence of monoisocyanate v / should be grounded here. The numerical mean is determined the molecular weight of the polymer. The degree of polymerization is calculated by dividing the Mn by the molecular weight of the repeating unit in the polymer chain diffused.

Then the amount of monoisocyanate, preferably phenyl isocyanate, which would be required to limit the formation of the polyiminoimidazolidinedione (PPA-M) to one certain target value of the degree of polymerization below the theoretically possible value that would be obtained if the Polymerization to its fullest extent would be calculated using the following Equation / by R. W. lenz, Organic Chemistry of Synthetic Polymers, page 56 (1967J7 ·

1 + r - 2 rp

(Equation 1),

where DT = the average degree of polymerization

r ■ = mol HCU / Clol diisocyanate or mol dicyanoformamide / mol Diisocyanate

or 1 in the case where cyanoformamidyl isocyanates are used, and

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* ν.

ρ = the heat conversion in the above equation

is ο

The reaction conversion ρ is then calculated from the above Equation using the DP value of the polymer that can be obtained without a monoisocyanate using a Molar ratio of reactants, r is obtained.

Then we modify equation 1 by changing r to r ¹

^W.

(Equation 2),

where DP = the target average degree of polymerization

r ¹ = mole HCN - (mole diisocyanate + mole monoisocyanate) or mole di cyanoformamide - ^ - (mole diisocyanate + mole monoisocyanate) or mole cyanoformamidyl isocyanate - (mole cyanoformamidyl isocyanate + mole monoisocyanate), and

ρ = the reaction conversion calculated in equation 1 is.

The value for r ¹ is calculated by inserting into equation 2 the target value for ΪΧΡ and the value for p as calculated in equation 1. The molar ratio of monoisocyanate / diisocyanate or cyanoformamidyl isocyanate, which is required to lower the average degree of polymerization to the target value, can be calculated from r ^1. The purity of the monomers and the solvent as well as the reaction conditions required to produce the poly (iminoimida-

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zolidinedione) to be used in the presence of monoisocyanate must be the same as in the original case has been used, meaning that no monoisocyanate is present was to "restrict the degree of polymerization".

The procedure described above is used for Control of the degree of polymerization in the reactions that Supply poly (iminoimidazolidinediones). The exact amount of monoisocyanate required per mole of diisocyanate or Cyanoformamidyl isocyanate is dependent on the purity of the Monomers, the solvent and the reaction conditions, which in turn limit the maximum degree of polymerization ", which can be achieved without a monoisocyanate.

In order to limit the degree of polymerization in the reactions described above, monoisocyanates of the following general formula used v / earth:

R-UCO,

where R = a Cp to Ccq> preferably Cg to Cpj and in particular a Cp to Cj ₈ organic part, such as an alkyl, aryl, alicyclic, alkylaryl group and such organic parts with or without substituents, but such substituents with the Isocyanate groups should not be able to react.

For specific examples of aryl isocyanates disclosed in

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Invention can include phenyl! Socyanate, Chlorophenyl isocyanate, bromophenyl isocyanate, tolyl isocyanate, Ethylphenyl isocyanate, naphthyl isocyanate, methoxyphenyl isocyanate, Esters of isocyanate benzoate, biphenyl isocyanate, etc. Alkyl isocyanates are methyl, ethyl, propyl, butyl, Pentyl, hexyl isocyanate, ethyl isocyanate acetate, benzyl isocyanate, etc. An alicyclic isocyanate is cyclohexyl isocyanate.

It should be pointed out that the molecular weight can also be reduced by not using equivalents molar amounts of HCK "and diisocyanates or diisocyanates and dicyanoformamides are used. However, it is preferred to have equal molar amounts of these reagents in the presence to use of monoisocyanates, namely from the for the following reasons:

(1) For better control of molecular weight.

(2) In order not to discard a large excess of HCH " or win back.

(3) To secondary reactions caused by the presence of diisocyanate in excess not to allow to occur.

The process for the preparation of poly (iminoimidazolidinediones) is known to the person skilled in the art from the preceding work known to the applicant and described in the above-mentioned patents »

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The Yerweadung of monoisocyanates has the advantage that no foreign bonds are introduced into the polymer "

The poly (iminoimidazolidinediones) can be hydrolyzed using "known processes that do not affect the chain length", after delivering more stable poly (parabanoic acids). If all other conditions "stay the same," determined because the degree of polymerization is not "influenced" by the hydrolysis is, the chain length of the poly (iminoimidazolidinedione) the final value of the inherent viscosity of the resulting poly (parabanic acid). For convenience, it is common to the term "target viscosity" interchangeable with "target value" the degree of polymerization to be used. Accordingly, while the process of the invention enables it, it becomes somewhere below the maximum value that without a chain terminator can be achieved to control, in many cases the target viscosity will be in the range of 0.75 to 1.5. It is further emphasize that the monoisocyanate functionality plays a key role. A different functionality can be used on the molecule as long as it is opposite the polymerization reaction is inert. Specific examples include:

halogenated monoisocyanate and tribromophenyl isocyanate » The invention is further illustrated by the following examples

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described. · ^ *

In the following examples, the poly (iminoimidazolidinediones), prepared by the process of the invention into the more stable poly (parabanoic acids) a subsequent acid hydrolysis, as already described, converted. This hydrolysis does not affect the degree of polymerisation. Indeed the molecular weight was of poly (parabanic acid), which are produced without monoisocyanates were used to calculate the amount of monoisocyanate required, the degree of polymerization to lower it to a specific value.

All intrinsic molar viscosities were determined in dimethylformamide (DMi ¹ ) at 25 ° C. using a polymer concentration of 0.5 g / 100 ml. Some examples were taken from the test facilities, but the amount of the compounds used in these examples is given for tests in the scope of the laboratory.

example 1

The polymer produced in this example had the maximum inherent viscosity (and thus a molecular weight and a degree of polymerization) as described using the compounds available and among those described Reaction conditions was obtained.

A solution of 250 g of diphenylmethane diisocyanate and 27.8 g

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Hydrogen cyanide in 2300 ml of dimethylformamide was prepared in a dry 3 liter flask equipped with a stirrer, thermometer and rubber partition. A solution of 0.098 g of sodium cyanide in 20 ml of dimethylformamide was then added to the solution with stirring at 30.degree. The temperature rises to 52 ^° C. After 30 minutes, a cold solution of 107 g of 96% sulfuric acid, 60 g of water and 150 ml of dimethylformamide was added to the solution of poly (iminoimidazolidinedione) to convert it into the corresponding poly (parabanic acid) to hydrolyze. After stirring for 30 minutes, the solution was poured into water and the polymer precipitated. It had an inherent viscosity of 2.27.

Examples 2-10

The number average molecular weight (276,000) of the in Polymer prepared in Example 1 was determined from inherent viscosity using the following Mark-Houwink equation

* inh ^{= 2} x ^{96 X 10} ~ ^{4 1} W ⁰ ' ⁷¹⁴

calculated. Using equations 1 and 2, the molar ratio of phenyl isocyanate to diphenylmethane diisocyanate was calculated to reduce the degree of polymerization to a predetermined value and used in these examples . The compounds used in these experiments come from the same lots as used in Example 1 became. Furthermore, the process variables were identical to those used in Example 1, except

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that phenyl isocyanate mixed with the solution of diphenylmethane diisocyanate and hydrogen cyanide in dimethylformamide
became. The inherent viscosity τοη each polymer was determined and compared with the desired “inherent viscosity” as the target value. The results are given in the table below:

example PhU00 ^a inn Target "inh 2 0.011 0.91 0.88 3 0.008 1.00 1.05 4th 0.008 1.01 1.05 VJI 0.008 1.06 1.05 6th 0.008 0.99 1.05 7th 0.008 1.00 1.05 8th 0.005 1.22 1.28 9 0.006 1.15 1.18 10 0.012 0.88 0.84

There was a molar ratio of phenyl isocyanate to diphenyl

Methandtlsocyanat calculated in each example and used to control the degree of polymerization so that a
Polymer with the specific target inherent viscosity was formed.

Inherent viscosity of each of the polymers actually made in Examples 2-10.

The results show that the degree of polymerization is more effective Way with a monoisocyanate such as phenyl isocyanate

? 0981

• 43.

can be lowered. In addition, the results show that the the amount of phenyl isocyanate required to limit the degree of polymerization can be calculated so precisely that the product has a predetermined inherent viscosity.

Example 11

Using diphenylmethane diisocyanate, the less was pure than that of Examples 1-10, the following experiment was carried out:

A solution of 135.5 g of diphenylmethane diisocyanate and 15.1 g of hydrogen cyanide in 1250 ml of dimethylformamide was in a 3 liter flask produced as in Examples 1-10. Then a solution of 0.053 g of sodium cyanide in 6.8 ml Dimethylformamide was added to the solution. After 30 minutes the poly (iminoimidazolidinedioh) that formed had hydrolyzed with a solution of 28.2 g of 96% sulfuric acid, 98 g of water and 98 ml of dimethylformamide. To The polymer was precipitated for 30 minutes, for which purpose the Pour solution in water into a Waring mixer. After washing with water, it was dried. It had an inherent viscosity of 1.47.

Examples 12-13

Two attempts were made using diphenylmethane diisocyanate from the same starting material as in the example 11 was used. The procedure was

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similar to that used in Example 1 except that 0.00287 g Phenyl isocyanate were mixed with the diisocyanate to obtain the To control the degree of polymerization so that a poly (parabanic acid) with an inherent "viscosity" of 1 can be obtained would. (It was calculated from the inherent viscosity of the product obtained in Example 11 that the reaction conversion ρ is 0.99628 and that the present 0.0053 moles of phenyl isocyanate per mole of diphenylmethane diisocyanate in the polymerization solution so lowers the degree of polymerization that a poly (parabanic acid) with an inherent Viscosity of 1). The following results were obtained:

Example inherent viscosity

12 0.96

13 1.06

Examples 14-15

To a solution of 252 g of diphenyl ether diisocyanate and 27.5 g Hydrogen cyanide in 2300 ml of dimethylformamide was added 0.125 g ITodium cyanide in 20 ml of dimethylformamide at room temperature. The solution was protected from atmospheric moisture and stirred for 30 minutes. Then 108 g. 96 ^ ige Sulfuric acid in 100 g of water and 100 ml of dimethylformamide were added to the polymer solution with stirring. The hydrolysis was finished within half an hour. The poly (parabanic acid) was precipitated in water, filtered, with water washed and dried. The inherent viscosity was

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² ' ⁸ ·. 4s.

Repeating the previous procedure in the presence of 1.16 g of phenyl isocyanate, the degree of polymerization will be as follows decreased so that the final product has an inherent viscosity of 1.03.

Examples 16 and 17

It became a poly (parabanoic acid) from diphenylmethane diisocyanate prepared as in Example 11, except that the diisocyanate comes from a different lot as it "has been used up to now." became. The polymer had an inherent viscosity of 1.40.

In order to prepare a poly (parabanic acid) having an inherent viscosity of 1.2 from the same compounds, it has been calculated that it is necessary to add 0.0015 moles of phenyl isocyanate per mole of diphenylmethane diisocyanate to the polymerization solution. Using this amount and using the same reaction conditions as in Example 16, the end product has an inherent viscosity of 1.18 _%

Examples 18 - 25 ''

These examples illustrate the utility of a variety of monoisocyanates in controlling the degree of polymerization during the production of a poly (parabanoic acid) from diphenylmethane diisocyanate,

The procedures used were essentially the same as used in Example 11. Tn example 18 the polymerization took place without a monoisocyanate, while in Examples 19-23 the polymerization was carried out in the presence of monoisocyanates. The results are summarized as follows:

Example no. Monoisocyanate Inherent Vis
kosity 1.65 18th no 0.86 19th 3-chlorophenyliso-
cyanate 1.05 20th O-tolyl isocyanate 1.07 21 Phenyl isocyanate 0.88 22nd Ethyl isocyanate acetate 0.98 23 Ethyl isocyanate

a -3

6.5 - ^ ₃ S x 10 moles of monoisocyanate per mole of diphenylmethane

diisocyanate.

The inherent viscosities of the products indicate that both aliphatic and aryl isocyanates help lower the Degree of polymerization during the formation of poly (parabanic acids) can be used.

Examples 2h - 25th

Example 11 was made using dimethylacetamide, N-methylpyrrolidone and dimethyl sulfoxide as solvents repeated.

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Example 26

The procedure of all examples is used, except that hydrogen cyanide is used in place of τοη dicyanq_formamide. *? - ''

Example 27

The procedure of all examples is used except that cyanoformamidylmethylphenyl isocyanate is used in place of HCN and Diisocyanate is used.

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Claims (9)

-Mt- Patent entitlements: HJ Process for controlling the degree of polymerization and thus the molecular weight of poly (iminoimidazolidinediones) (PPA-M), characterized in that a monoisocyanate is used. of the general formula R-KCO, where R is a C ₂ to C ₁ -Q organic moiety, any of the following reaction solutions (a) HCN + diisocyanate (Id) diisocyanate + di cyano formamide (c) Cyano formamideyl isocyanate admits. 2. The method according to claim 1, characterized that the amount of monoisocyanate is calculated in advance to produce polymers with the desired degree of polymerization to manufacture. 3. The method according to any one of the preceding claims, characterized in that as Diisocyanate Diphenylether diisocyanate or diphenylmethane diisocyanate used. 4. The method according to any one of the preceding claims, characterized in that as Conoisocyanate phenyl isocyanate, 3-chlorophenyl isocyanate, ololyl isocyanate, Ethyl isocyanate and / or ethyl isocyanate acetate used. 709815/1065 5. A method for controlling the intrinsic molar viscosity of a poly (parabanic acid), characterized in that a poly (iminoimidazolidinedione) according to the
Process according to any one of claims 1-4 and then preparing the product by means of acid hydrolysis with the formation of a poly (parabanic acid) with the desired inherent target viscosity. 6. The method according to claim 5, characterized in that the target viscosity of 1 + 0.1
wish. 7. The method according to any one of the preceding claims, characterized in that the monomers used are HCIT and diisocyanate and that the reaction
is catalyzed by cyanide ions. 8. The method according to any one of claims 1-6, characterized in that the monomers used are diisocyanate and dicyanoformamide are used. 9. The method according to any one of claims 1-6, characterized in that one is used as the monomer Cyanoformamidyl isocyanate is used. 709815/1068