DE1812133A1 - Polymers based on gamma, gamma-dialkyl-delta-valerolactones - Google Patents

Description

Polymers based on #, # -dialkyl- # -valerolactones.

The polymerization of unsubstituted # -valerolactones is known. Catalysts include alkyl compounds of elements from III. and V. group of the periodic table. Furthermore, for the polymerization of α, α-dimethyl- # -valerolactone the use of group V alkylene and for polymerization of ß-methyl- # -valerolactone and the unsubstituted # -valerolactone the use known from n-butyllithium, 4-isohexylpyridyllithium and phenylpotassium.

For the polymerization of the valerolactones doubly substituted in the J'-position however, many of the aforementioned catalysts are unsuitable. So stands presumably consistent that the #, # -dialkyl- # -valerolactones even at temperatures Above 1000C they have no tendency to spontaneous polymerization.

It has now been found that #, # -dialkyl- # -valerolactones of the general formula or mixtures thereof with good yields using organometallic compounds of the metals of subgroup II of the periodic table as initiators at temperatures from -20 to + 2000C, preferably +40 to + 80 ° C.

In the above formula, the radicals R1 and R2 are intended to be the same or different aliphatic alkyl groups with 1 to 18 carbon atoms, preferably 1 to 8 carbon atoms, mean. #, #, -Dimethyl- # -valerolactone is particularly preferred.

It is also possible to carry out the polymerization as a mixed polymerization to be carried out with the additional use of other lactones, which are derived from the dialkyl 3 -valerolactones are different, in amounts from 0.1 to 99% by weight, preferably 0.5 up to 45% by weight, based on the total amount of the polymer sats.

The process can be carried out as a bulk polymerization without being present or carried out in the presence of only small amounts of solvents or diluents will. The preferred solvent is only an amount of 0.2 to 5% by weight, based on the monomers, used to add the catalyst in dissolved form to be able to. However, larger amounts of a solvent are also possible, if necessary up to 50% by weight and above to be used.

Suitable solvents or diluents include: hydrocarbons, such as benzene and its homologues, chlorinated hydrocarbons, tetrahydrofuran and 1,4-dioxane. It is also possible to do the later during the polymerization to add the compounds mentioned which are suitable as solvents for the polymer, with the exception of those that decompose the catalysts.

The water content of the dialkylvalerolactones and any added Solvent should be below 0.01% by weight.

As organometallic compounds of metals of sub-group II of the periodic system are to be understood as those of zinc, oadmium, and mercury will. The organic radicals of these organometallic compounds can be aliphatic, be cycloaliphatic or aromatic radicals, which may be unsaturated can. The metal alkyls with C1 to C6 in the lipatic radical and are preferred of these, the zinc alkyls are used again.

Suitable organometallic compounds are, for example, dimethyl zinc, Diethyl zinc, dipropyl zinc, di-o-tolyl zinc, dicyclohexyl zinc, diethyl cadmium, di-n- and di-i-butylcadmium, diisoamylcadmium, dimethylmercury, dipropylmercury, Dibenzyl mercury, diphenyl and ditolyl mercury, etc.

The reaction is carried out in general so that the dried Monomers after the air by repeated evacuation or purging with nitrogen removed.wurde, are mixed with a solution of the initiator. The reaction mixture is heated to the reaction temperature with stirring. After turning off the stirrer the polymerization temperature is maintained until the polymerization has ended; after 15-20% conversion of the polymerization batch solidifies to a solid mass.

The polymer can then be dissolved in suitable solvents and precipitated, for example, with alcohols as a homogeneous, colorless, flaky or fibrous product and be dried.

Suitable solvents for the polymers are chlorinated hydrocarbons, such as chloroform, methylene chloride or carbon detrachloride, hydrocarbons, how. Benzene and its homologues, ketones and ethers such as acetone, 1,4-dioxane or tetrahydrofuran Nitrobenzene, Hexamethylphosphorsuretriamid, Dimethylformamide, as well as numerous Further. In general, the polymer is at an elevated temperature or at the boiling point of the solvent dissolved and precipitated again on cooling. In some Solvents, In tetrahydrofuran, among other things, the polyester remains in solution when it cools and becomes with Alcohol like. The same applies to those which are partially soluble in the cold Copolymers.

The organometallic compounds used as initiators are generally in amounts of 10-4 to 1, preferably 10-3 to 10 2, moles per mole of the monomers are used, but proportions below and above can also be used Find use.

The use of more than 2 x 10-3 moles of initiator per mole of monomers give good yields and high molecular weights. On the other hand, amounts above 4 × 10 3 mol of initiator no reduction in the yield, but lower the molecular weight.

Other comonomers of the respective t dialkyl-8-valerolactones various iactones usable, such as 8-valerolactone, # -caprolactone, fl -propiolactone, ß-trichloromethyl-ß-propiolactone and mixtures with others alkyl substituted valerolactones. The proportion of comonomers can be 0.1 to 99% by weight, preferably 0.5 to 45% by weight, based on the total amount of monomers.

The polymers obtained generally have molecular weights between 10,000 and 15,000, yes are also molecular weights up to 200,000 and above possible. When using toluene as a solvent, this can Molecular weight can be adjusted (see. Examples 8-14).

The softening range of the polymers obtained depends on the type of alkyl groups in the t-position and is generally between 105 and 12,000. The softening range was measured on the Kofler heating bench.

It has been found that polyesters according to the invention have a high resistance to hydrolysis own. The resistance to hydrolysis was measured on films 0.1 mm thick against water, Dilute caustic soda and dilute sulfuric acid are measured, being viscosimetic Measurements to determine any hydrolytic degradation that may have occurred served.

It was determined by radiography that the obtained Polymers are highly crystalline.

The polymers obtained can be processed into molded articles of all types become, especially those that predominantly have one or two directions of expansion have, for example, threads, fibers, rods, tapes, foils and plates.

So it is possible from the melt, for example at 130 ° C and above, to spin threads directly. These threads have a high aliphatic polyester content Tensile strength in the range of 400 - 500 kg / m2 and higher.

However, it is also possible to use threads and fibers from solutions of the polymers to manufacture. The solvents already mentioned are preferably used.

The solvent evaporates during the manufacturing process.

Those produced by the dry spinning or wet spinning process Threads can be stretched 2 to 6 times their length.

By quenching the melt, largely transparent ones can be made Produce polien with high tensile strength.

bue solutions of the polymers in the solvents already mentioned, Foils and plates, which are usually opaque, can be cast preferably in chloroform.

At temperatures in the range from 85 to 15,000, the polymers press under pressure to form moldings, for example using the injection molding technique.

In the following examples, the reduced viscosity was # eSp / c (ml / g) in chloroform at a temperature of 2000 and a concentration of c = 0.01 g / ml measured.

The molecular weights were determined by vapor pressure osmometry.

The Vicat was determined according to VDE 0302 in glycol with a load of 5 kg.

Percentages relate to% by weight, conversions and yields are given in% by weight.

The sizes M1 and M2 mean the molar concentrations in the starting mixture, m1 and m2 are the molar proportions in the copolymer, the expressions M1 / (M1 + M2) and m1 / (m1 + m2) the mole fractures. The copolymerization parameters r1 and r2 are as a ratio defined by the rate constant.

Example 1a 12.4 g of #, # -dimethyl- # -valerolactone (9.6, 10-2 mol) with a water content below 0.02 wt .-% are at room temperature with exclusion of air with 0.2 ml of a solution of Zn (C2H5) 2 in benzene (10 mol of Zn (C2H5) 2 per ml of benzene) added (molar ratio of initiator / lactone = 2 10-3). It is kept at 700C for 24 hours warmed up. The reaction mixture solidifies to a solid mass. For the separation of Catalyst and unreacted monomer is the reaction mixture in 70 ml of chloroform dissolved and precipitated in 600 ml of methanol.

Yield: 9.60 g Conversion: 77% Molecular weight: 40,000 - 50,000 Softening range: 108-110 ° O # sp / c value: 93.7 ml / g The polymer is in chloroform at room temperature and methylene chloride soluble; it is at 70 ° C (or at the boiling point of the solvent) soluble in hexamethylphosphoric acid triamide, dimethylformanide, tetrahydrofuran, 1,4-D @ oxane, Toluene, benzene, acetone, nitrobenzene and carbon tetrachloride. Falls as it cools the polymer @ u @ @@@ @ named solvents again; only with Te - @@@ h @ @ran ver @@@ is the polybei @@@ ühlen dissolved in the heat in Lö @@@@@ @@@@@@ @@@@@ ne @ @@@@ @ @@@@ Mange #, # -mäthyl @@@ @n, instead of i @@ #, #, -Dimethyl- # -va @@ rolactons, will with a corresponding conversion, a polymer with similar physical properties obtain properties.

Example 1b For the following technical tests, an example is used 1a produced poly- #, # -dimethyl # -valerolactone used: From the melt At 120 - 130 ° C, threads are spun that are three to four times their length can be stretched.

Opaque films can be cast from a 2Q% solution in Ohloroform.

Opaque foils can be poured from the melt.

By quenching the still hot foil with liquid air largely transparent foils produced.

At temperatures of 90 - 100 ° C, under a pressure of 300 kg / cm2, moldings can be pressed.

Example 2a In a three-necked flask with a capacity of 500 ml, which is equipped with a KPG stirrer, Rubber cap and gas inlet tube, 310 g #, # -Dimethyl- # -valero- @ acton (2.42 mol) given with a water content below 0.02% by weight. After evacuating several times and filling with dry, air-free Nitrogen, 4.85 ml of a Zn (02H5) 2 solution in benzene (10-3 3 Moles per ml of benzene) with a medical syringe through the rubber cap injected and the reaction mixture heated to 7000. After half an hour the stirrer is switched off. The polymerization batch solidifies into a solid, opaque mass.

After a reaction time of 24 hours, it is dissolved in 1200 ml of chloroform and the Polyester precipitated in 9 l of methanol as a fibrous, colorless product. The polymer is dried over P205 at room temperature. For purification, from CHCl3 with methanol fell over.

Yield: 228 g Conversion: 73.5% # sp / c value: 101.6 ml / g Vicat: 81-86 ° C (depending on the crystallinity) Solubility and softening range correspond the product according to Example 1 When using ä @@ equivalent amounts of Zn (i-C3H7) 2 or Zn (n-04H9) 2, instead of the Zn (C2H5) 2 solution, and when the polyester is dissolved in acetone and cases in ethanol, similar results were obtained.

The solvent-precipitant mixture is used to recover the unreacted monomer (1.2 1 CHCl3 and 9 1 methanol) distilled off under normal pressure over a packed column and the backlog (to Oligomer cleavage) heated to 200 ° C. Afterward the lactone was distilled under vacuum over a Vigreux column.

Bp24 = 104-107 ° C; Yield: 64 g. Example 2b Using Poly - #, # -dimethyl- # -valerolactone prepared according to Example 2a are as follows Measurements carried out: At a pressing temperature of 140 ° C, a 1 mm thick Plate made.

Tensile strength (DIN 53 455): 408 kg / cm2 with an elongation of 10%.

After the injection molding process (injection temperature in the piston 1500C) Standard bars produced: impact strength (DIN 53 453): 57.3 to not broken.

U-notch toughness (DIN 53 453): 4.5 kp cm / cm2.

Example 3 As in Example 1, 7.75 g of #, # -dimethyl- # -valerolactone (6.10 2 mol) with 0.24 ml of a solution of Zn (C2H5) 2 in benzene (10-3 mol per ml Benzene). Molar ratio of initiator / lactone = 4. 10-3.

Polym. Temp .: 70 ° C; Polym. Time: 24 hours

The work-up is carried out as in Example 1.

Yield: 5.79 g Conversion: 74% # sp / c value: 51.3 ml / g; Molecular weight: 10,000-15,000.

Example 4 Analogously to Example 1, 13.17 g of #, # -dimethyl- # -valerolactone are obtained with 0.3 ml of a solution of ZntC2H5) 2 in benzene (0.5.10-3 mol Zn (C2H5) 2 per ml Benzene).

Initiator / lactone molar ratio = 1.5. 10-3.

Polym. Temp .: 700C; Polym. Time: 40 hours

Yield: 3.30 g; Conversion: 25 ffi # sp / c value: 82.7 ml / g; Molecular weight: 25,000 - 30,000 an addition of 0.1 mol% (0.015% by weight) of water, based on the monomer, or 50 mol%, based on the catalyst (initial molar ratio of initiator / lactone = 2 10-3) brings the catalyst activity to a virtual standstill.

Example 5 6.97 g of #, # -Dimethyl- # -valerolactone (M1) (5.4, 10-2 Mol) and 0.6 g # -valerolactone (M2) (Q, 6 10-2 mol) are with the exclusion of air and moisture at room temperature with 0.25 ml of a solution of Zn (C2H5) 2 in benzene (0.5 10-3 mol Zn (C2H5) 2 per ml of benzene).

Initiator / monomer molar ratio = 2 10-3. It is 1/4 hour at 70 ° C warmed up. The reaction mixture solidifies to form a homogeneous, transparent mass. The polymerization is terminated after this time with moist chloroform, the Reaction mixture dissolved in 40 ml of CHCl3 and the copolymer in 400 ml of methano ' failed.

Yield: 2.65 g Conversion: 34% M1 / (M1 + M2) = 0.9 m1 / (m1 + m2) = 0.6 The polymer has a melting temperature of 78 ° C. (Kofler bench) and shows a compared to poly- #, # -dimethyl- # -valerolactone, significantly increased elasticity. It is soluble in CHCl3, tetrahydrofuran, dioxane, toluene, benzene at room temperature and nitrobenzene for the system #, # -dimethyl- # -valerolactone (M1) - # -valerolactone (M2) the parameters were determined as follows: r1 = 0.1; r2 = 2.4 example 6 6.20 g #, # -Dimethyl- # -valerolactone (M1) (4.8. 10-2 mol) and 1.37 g # -caprolactone (M2) (1.2. 10-2 mol), under air and with exclusion of moisture at room temperature with 0.5 ml of a solution of Zn (C2H5) 2 in benzene (0.5.10-3 mol Zn (C2H5) 2 per ml Benzene). Molar ratio of initiator / monomer = 4 @ 10-It is 10 minutes at 70 ° C heated The reaction mixture solidifies to a transparent, homogeneous mass.

The work-up was carried out as in Example 5.

Yield: 0.92 g Conversion: 12.8% M1 / (M1 + M2) = 0.8; m1 / (m1 + m2) = 0.75 The polymer melts on the Kofler bench at approx.

75 ° C. It is more elastic than poly- #, # -dimethyl S-valerolactone. It is soluble in CHCl3, OH2C12, tetrahydrofuran and benzene at room temperature.

For the system #, # -dimethyl- # -valerolactone (M1) - # -caprolactone (M2) the parameters were determined as follows: r1 = 1.6 and r2 ~ 4.3. Example 7 Resistance to hydrolysis of poly- #, # -dimethyl- # -va lerolacton: The polyester according to Example 1a is in Form of thin films (approx. 0.1 mm thick) from the action of water, aqueous sodium hydroxide solution and aqueous sulfuric acid, and hydrolytic acid that may have occurred Degradation followed by viscometric measurements. The duration of the experiment is 8 days.

The polymer proves to be resistant at room temperature against water, .2 N aqueous NaOH and 10% aqueous H2S04, while boiling Water attacks the polyester (slight decrease in viscosity; strongly increasing brittleness of the films).

Examples 8-14 Analogously to Example 2, but using toluene as the solvent, the polymerization of #, # -dimethyl- # -valerolactone is carried out at 50 ° C. with Zn (C2H5) 2 as the catalyst; Initiator concentration: 1.6. 10-2 moles / 1; Polymerization time: 4 hours Example monomer conc. Turnover # sp / c molecular (Vol -%) *) (wt.%) (Ml / g) weight 8 100 90.5 188 150 000 9 92 92.3 166 110,000 10 85 93.4 158 100,000 11 71 85.4 108 50,000 12 57 76.9 73 25 000 13 43 52.3 63 20,000 14 28 25.5 26 5,000 *) Density of the lactone d425 = 1.015

Claims (5)

Claims 1. Polymers based on # -dialkyl- # -valerolactones or mixtures thereof, in which monomer units of the general formula Polymers of the formula form, in which the radicals R1 and R2 are identical or different aliphatic alkyl groups having 1 to 18 carbon atoms, preferably t to 8 carbon atoms, and the degree of polymerization n is 50 to 100,000. 2. Polymers according to Claim 1, the further one of the alkyl valerolactones various lactones in amounts of 0.1 to 99% by weight, preferably 0.5 to 45% by weight, based on the total amount of monomers, copolymerized. 3. Process for the preparation of polyesters by polymerization and copolymerization of lactones in the presence of metal compounds as catalysts, characterized in that #, # -dialkyl- # -valerolactones or mixtures thereof of the general formula optionally together with other lactones different from the #, # -dialkyl- # -valerolactones, using organometallic compounds of the metals of subgroup II of the periodic table as initiators at temperatures from -20 to + 200 ° C, preferably +40 to 80 ° C, polymerized. 4. The method according to claim 3, characterized in that the Polymerization in the presence of solvents in amounts from 0.01 to 50% by weight, preferably 0.2 to 5.0% by weight, based on the monomers. 5. Shaped bodies made of, or essentially under ', application of polymers based on #, # dialkyl # -valerolactones.