DD146053A1 - METHOD FOR PRODUCING ESTER GROUP-POLYOLEFINEN DERMINATED POLYOLEFINES - Google Patents

Abstract

The invention relates to a process for the preparation of ester-group-terminated polyolefins of a certain molar mass by metathesis degradation of unsupported polymers with unsatured organic diesters. The aim of the invention is to represent these ester group-terminated polyolefins with small amounts of catalyst, high yields and the desired molecular weight. Task is the development and selection of suitable catalysts and Prozeszbedingungen for the above method. According to the invention, the problem is solved by carrying out the process known per se with catalysts which, in addition to the generally necessary transition metal component of the 5th to 7th subgroups, contain an organoelement compound of the 4th main group as cocatalyst. Polymer degradation occurs at temperatures between +25 and +150 degrees C. The unsaturated diester does not destroy the catalyst even at 100 to 200 fold excess. Almost quantitative polyolefin yields and the desired molecular weights are achieved. The rubbery, syrupy or oeligen telechelic polyolefins are of interest as prepolymers or oils, additional components and binders in the paint and paint industry.

Description

Process for the derivation of ester group-terminated polyolefins

Anwendungsgebi et he invention

The invention relates to a process for the preparation of ester-group-terminated polyolefins of specific average molecular weight by metathesis degradation of unsaturated polymers in whose main chain is not completely substituted double bonds, by means of unsaturated dicarboxylic acid esters or diesters of unsaturated dialcohols. According to this method, solid rubbery but also syrupy to oily telechelic polyolefins of very different chain structure can be prepared. "Such products have two reactive end groups and are of particular interest as prepolymers, except as model polymers for basic investigations. These can be converted with suitable coupling components into relatively high molecular weight, linear or crosslinked polyolefins. * Further possible applications are in use as modifiers for rubber and as additional components, oils or binders for paints and coatings.

In the direct application, the ester group terminated polyolefins can be modified both in the chain, at the end groups or by additions according to the usual methods in polymer chemistry. "This list of potential applications is not exhaustive, but the meaning of" telechelic polymers "and the need for

To illustrate the development of suitable and technically feasible presentation methods.

Characteristic of the known technical solutions

Telechelic Polyalkenamers can be obtained in various ways from 1,3-dienes · So you can by anionic polymerization of dienes, z. B · butadiene, alkali metal-terminated polyolefins of certain molar masses which are easy to convert into hydroxy- or carboxy-terminated diene polymers · similar products, preferably with mercapto end groups, are obtained by radical diene polymerization using suitable bifunctional regulators. The selective presentation of polyolefins having two reactive end groups by the above processes remains a general problem. In addition, the recovery of telechelic polyolefins with other chain members or the preparation of telechelic copolymers of defined structure is not possible with the diene polymerization processes mentioned.

One known method of selectively introducing two functional end groups into the polymer molecule, controlling the molecular weight, and realizing a wide variety of chain structures is olefin metathesis. After this synthesis principle estergruppenhaltige polyolefins can be displayed are two "

Ring · By ring-opening polymerization of cycloolefins with unsaturated organic diesters and

2 · by metathetic degradation of unsaturated polymer chains with unsaturated organic diesters

The ring-opening polymerization of cycloolefins in the presence of acyclic ester-functionalized olefins, olefinic mono- and diethers, and unsaturated alkylhalosilanes as regulators and end group promoters has been described for the first time by STRECK and WEBER (DT-OS 2028935, DT-OS 2027905 and DT-AS 2157405). Another patent for the polymerization of cycloolefins with unsaturated dicarboxylic acid esters is from FURUKAWA et al. (JA-PS 77/151400).

The second synthetic route, the metathesis degradation of unsaturated polymers by means of acyclic unsaturated diesters, has also already been realized and is described by PURUKAWA et al. in a Japanese patent specification JA-PS 77/151389 secured · According to STRECK and WEBER succeed in this way also the recovery of silyl group-containing telechelic polyolefins (DT-A3 2157405).

As catalysts for the ring-opening polymerization of cycloolefins and the Metatheseabbau of unsaturated polymers with said heteroatom-containing acyclic olefins two- or multi-component systems were generally used, the metals of the 5 · to 7 · transition group or their compounds and an organometallic compound of 1 to 3 «main group as essential ingredients. However, only catalysts in which tungsten or molybdenum, preferably in the form of tungsten hexachloride and molybdenum pentachloride, and as a cocatalyst, an organoaluminum component, for example ethylaluminum dichloride or diethylaluminum chloride, has been the main focus of experimental use have so far been used. Activity and selectivity-improving effects occasionally occur achieved by addition of so-called activators or activating regulator consisting of saturated or unsaturated hydrocarbons with hydroxyl, mercapto, ester or ether groups.

Me methods for metathesis degradation of unsaturated polymers have compared to the generally bound to the use of cycloolefins Ringöffnungspolymerisation a much wider range of applications and allow the production of a very extensive range of products. This is due to the fact that apart from polyalkenamers it is also possible to use diene polymers, copolymers and otherwise prepared and modified polyolefins.

The known technical solutions for metathesis degradation of unsaturated polymers have several, for the process control crucial deficiencies · Thus, the production of telechelic polymers with relatively low molecular weights,

d. h. Liquid polyolefins in the range of 500 to 10,000, only when using very high catalyst concentrations. Since the heteroatom-containing olefins necessary for the molar mass act as LEWIS bases, in the abovementioned catalysts complete deactivation can only be achieved by a corresponding excess of the LEVIS acid organometallic cocatalyst can be avoided.

A further disadvantage of the degradation processes described hitherto is the degree of conversion, which in some cases is small or insufficient for accurate mass control, despite the high catalyst concentration. The cause lies in the low chemical resistance of the catalysts used and in their inadequate thermal loadability, which, for example, works at temperatures above +50 C excludes Purely the targeted recovery of bifunctionalized polyolefins, however, a quantitative degradation of the unsaturated polymer used is essential.

As a shortcoming is to be considered ultimately that the amount of regulator necessary for a certain average molecular weight must generally be determined empirically, since a part of the regulator is always blocked by the .LEWIS-acidic catalyst ·

Object of the invention .

The object of the present invention is to present the ester group-terminated polyolefins with small quantities of catalyst, high yields and the desired molecular weight.

Explanation of the essence of the invention

The object of the invention is to select catalysts and process conditions for carrying out the process for the metathetic degradation of unsaturated polymers by means of unsaturated diesters for the preparation of ester-group-terminated polyolefins so that the abovementioned deficiencies do not occur *

According to the invention the object is achieved in that the known method is carried out with catalysts,

containing as essential constituents a compound of an element of the 5 · to 7 · lifting group and as a second component an element organic compound of the main group · The coming as a transition metal component in embossing compounds correspond to those in the already known technical solutions for the Metatheseabbau of unsaturated polymers Unsaturated diesters It is of crucial importance for the realization of the technical problem, however, that cocatalysts are used which contain organyls of silicon, germanium, tin or lead. The tin tetraalkyls, such as, for example, are particularly effective catalytically. B. tetramethyl or Tetraäthylzinn. A further advantage is that these compounds are resistant to air and hydrolysis, which in the organometallic compounds of.1. to 3 · main group does not apply. To solve the technical problem, it is necessary to carry out the polymer degradation in the temperature range of +25 ⁰ C to +150 ⁰ C. The best results, ie a high or complete degree of conversion, can be achieved at temperatures between +75 ⁰ C and +120 ⁰ C. The order of addition of the substrates and catalyst components exerts no significant influence on reaction course and implementation sgr ad.

The catalyst concentration, regardless of the molecular weight of the telechelic polyolefins to be adjusted, can generally be chosen to be lower than in the previously patented processes. Almost complete reactions of unsaturated polymer and diester are achieved in the molar ratio range transition metal to unsaturated monomer units of the polymer from 1/10 to 1/5000, preferably 1/100 to 1/2000. The ratio of transition metal component to cocatalyst is 1 / 0.5 to 1/10, preferably 1: 2.

The necessary regulator amount depends on the number of double bonds in the polymer used and the desired average molecular weight of the ester group-containing polyolefins. Pur the M range 500 to 10,000, i. oily to syrupy. Products, the molar ratio of unsaturated monomer units of the polymer used to diester is about 1000/5 to

1000/200 · For the preparation of rubbery polyolefins, the regulator concentration must be lower · In contrast to the catalysts used hitherto, even a hundred to two hundredfold molar excess of the diester with respect to the catalyst does not lead to any deactivation of the syst one β

In analogy to the already known processes are used as unsaturated polymers hydrocarbons in the main chain are not completely substituted double bonds. "These include on the one hand the so-called polyalkene, which are accessible by Ringöffungspolymerisation of cycloolefins · On the other hand, also prepared by the technical methods for diene polymerization polyolefins, such as _e 1,4-cis-polybutadiene are used to reduce · there are the different variations of copolymers recordable as ABT or SB rubber and modified in the chain, e.g., "B · partially halogenated, hydrogenated or cross-linked polyolefins ·

As regulators, as in the already known processes, unsaturated diesters are used which can be derived from both an unsaturated dicarboxylic acid and an unsaturated dialcohol, provided there is at least one - optionally substituted - methylene group between double bond and ester groups on both sides for example, dimethyl 2-butenedicarboxylate, dimethyl 3-hexenedicarboxylate, dimethyl 8-hexadecylenedicarboxylate and 1,4-diacetoxy-2-butene.

In a known manner, the polymerization is carried out in the presence of an inert solvent suitable for reactions with ZIEGLER-NATTA catalysts. The type and amount of solvent are determined essentially by the solubility or swelling capacity of the polymeric starting materials and the molecular weight of the end products.

To terminate the catalysis, the catalyst is deactivated by means of a proton-active substance, preferably an alcohol. The separation and purification take place according to the procedure customary for polyolefins.

embodiments

(see Table 1)

Metathesis degradation of 1,4-cis-polybutadiene with 3-hexenedicarboxylic acid dimethyl ester with variation of the substrate and regulator concentration ·

In a reaction vessel are 2 g of 1,4-cis-polybutadiene (96.6 % '1,4-cis, 2.3 % 1,4-trans, 1,1 % 1,2-double bonds, molecular weight M _n ^ 100,000) swollen long C for one hour in 20 ml of chlorobenzene at 60 ⁰ or dissolved · Thereafter, the appropriate quantity of 3-Hexendicarbonsäuredimethylester to · in a second reaction vessel, which is connected to the first by a bend, the catalyst is prepared , The calculated amount of tungsten hexachloride is charged with 2.5 ml of chlorobenzene and then added dropwise a solution of the cocatalyst tin tetramethyl in 2.5 ml of the same solvent with stirring (molar ratio of WCIg: Sn (CHO = 1: 2) · After 5 minutes, pour the In the course of the reaction, the color of the solution changes from reddish brown to dark brown and the viscosity of the reaction solution decreases, and 0.5 ml of methanol are added to terminate the catalysis.

For workup, the reaction solution is poured through a paper filter in 50 ml of methanol, which is provided with 5 mg of phenylnaphthylamine as a stabilizer. The methanolic suspension is stirred vigorously. The oily, syrupy or solid polymer is again dissolved in 5 ml of methylene chloride for purification, again precipitated in 50 ml of methanol and dried for 3 days in vacuo at ca * 1 Torr and 50 ° C. The products are colored pale yellow to light brown, depending on the purity ·

To analyze the estergruppenterminierten polymers, the molecular weight was determined by vapor pressure osmometry in toluene at 42 ⁰ C · The content of 1,4-cis and 1,4-trans double bonds was determined by the IR spectrum of the polymers.

Attempt Hr.

molar ratio

WC1 _A : Diester o

Molecular weight Yield C, H ^ -mono-, exp. % unit

1 1 i 3.9 : 200 3000 2970 92 2 1 ί 19.3 ι 1000 3000 3100 8.9. 3 1 i 38.6 ι 2000 3000 3210 88 4 1 ; 19.3 t 1000 3 QOO 3100 90 5 1 : 11.7 : 1000 5000 5160 91 6 1 : 5.5 ί 1000 10000 9770 91

Table 1: Metathesis degradation of cis-1,4-polybutadiene with 3-Hexendicarbonsäuredimethylester under variation of the substrate and regulator concentration; Reaction temperature T _R = 100 ^° C.,

reaction time

= 4 h;

1) based on. used polybutadiene

X i ^ -i. 15 (see Table 2)

Metathesis degradation of 1,4-cis-polybutadiene with 3-Hexendicarbonsäuredimethylester under variation of reaction temperature and time.

The experiments were carried out analogously to the instructions for Examples 1 to 6, "The polymer yields are 90%. At reaction times of less than 2 hours and temperatures of 75 ^° C., however, complete degradation is no longer achieved.

eat

(see Table 3)

Metathesis degradation of 1,4-trans-polybutadiene with 3-Hexendicarbonsäuredimethylester. .

The experiments were carried out analogously to the instructions for Examples 1 to 6. The solid 1,4-trans polybutadiene used had a content of 96.5 % trans and 3.6 % 1.2 units. The IR spectroscopic determination of the microstructure of the degradation products containing ester groups gave values of

attempt 6 Molverhältms No. V 1 i : Diester: G. 7 1 . i 3.9 s 8th 1 . : 19.3 9 1 year ι 38.6: 10 1 . : 19.3: 11 1 i : 19.3 i 12 1 : s 19.3: 13 1 : 19.3! 14 1 : : 19.3 15 : 19.3. : 200 : 1000 : 2000 , 1000 , 1000 : 1000 , 1000 : 1000 : 1000

microstructure

Monomer unit h ⁰ C % 1,4-cis % 1,4-trans % 1,2

Molar mass ¥ _n (exp.)

100

100

100

100

100

100

100

94.4

95.7

31.5

46 41 24.8

42.3 42

55

 4.4 3.3

1.5 1.5 0.7 1.2 1.2 1.0 1.0 1.3 1.0

2970

3100

3210

3080

3820

4040

5820

10350

12400

Table 2: Metathesis degradation of 1,4-cis-polybutadiene with 3-Hexendicarbonsäuredimethylester under variation of the reaction conditions

- 21% 1,4-cis, 77> 1,4-trans and 2% 1,2-units.

attempt

molar ratio

: Diester: C / ^H 6 ""

Molar mass yield ^over * ^{exp #} ^

Monoraereinheit

16 1 : 3, 90: 200 4 3000 3050 89 17 1 : 3, 90: 200 2 3000 3160 88 18 1 : 1, 95: 100 4 3000 89

Table 3: Metathesis of 1,4-trans-polybutadiene with 3-Hexendicarbonsäuredimethylesterj reaction temperature T _R = 100 ⁰ C; 1) based on the polybutadiene used

Claims (6)

1 · Process for the preparation of ester-group-trained polyolefins of specific average molecular weight by metathesis degradation of unsaturated polymers in the main chain are not fully substituted double bonds, by means of unsaturated dicarboxylic acid esters or diesters of unsaturated dialcohols in the presence of catalysts, the compounds of elements of the 5 · to 7 · life group contain, characterized in that the second catalyst component used is an organometallic compound of the main group of the Periodic Table, the polymer degradation is to be carried out at temperatures of from 25 ^° C. to 150 ^° C., and also a high excess of diester does not significantly affect the catalytic activity of the system. 2. Method according to item 1, characterized in that the second catalyst component used is an organo compound of silicon, germanium, tin or lead, preferably a tetraalkyltin compound. 3 · procedure according to point 1, characterized in that the process is carried out at reaction temperatures of 25 ⁰ C to 150 ⁰ C, preferably in the range of 75 ° C to 120 ⁰ C · 4. Method according to item 1, characterized in that the molar ratio of the transition metal compound to the second catalyst component is between 1 / 0.5 and 1/10, preferably 1/2 5 · procedure according to point 1, characterized in that the molar ratio of transition metal component to unsaturated monomer units of the polymer used is in the range of 1/10 to 1/5000, preferably 1/100 to 1/2000 · 6 · procedure according to point 1, characterized in that the molar ratio of diester to unsaturated monomer units of the polymer used ren at 200/1000 to 5/1000 and syrupy or oily ester group terminated polyolefins arise
Method according to item 1, characterized in that the molar ratio of diester to unsaturated monomer units of the polymer used is less than 5/1000 and solid or rubbery ester group-terminated polyolefins are formed.