Reactive functional siloxane compositions

Abstract

Disclosed herein are compositions, comprising linear polydiorganosiloxanes having enhanced reactivity and their use to prepare polydiorganosiloxane-polyorgano block copolymers.

Claims

1. A composition comprising: (A) one or more polydiorganosiloxanes selected from the formulas (I) and (II): ##STR00015## wherein each occurrence of En is independently selected from the group consisting of hydrogen and —C(═O)—OR.sup.1, wherein R.sup.1 is selected from the group consisting of alkyl, alkylaryl, and aryl groups, each group having up to 30 carbon atoms, T is independently selected from the group consisting of divalent optionally substituted hydrocarbyl residues having up to 60 carbon atoms, optionally comprising one or more heteroatoms, said group T being bond to Si and O-En via a carbon atom, which groups T are selected from (Si shown for indicating binding direction of T):
Si-(alkyl)-(aryl)-
Si-(alkyl)-O-(aryl)-
Si-(alkyl)-O—C(O)-(aryl)-, and
Si-(alkyl)-O-(alkyl)-, Ar is independently selected from the group consisting of divalent aromatic residues having up to 60 carbon atoms which can be independently from each other substituted with a substituent selected from the group consisting of halogen, alkyl and alkoxy groups, R is an organic group having up to 30 carbon atoms, n is an average value of from 10 to 400, and m is an average value of from 1 to 10 and (B) 0.02 to 5.0 mmol/kg of the total of weight of (A) and (B) of one or more organic or inorganic salts selected from the group consisting of alkali metal salts and alkaline earth metal salts.

2. The composition of claim 1, wherein the organic or inorganic salt is selected from the group consisting of salts of acids having a pK.sub.A of 3 to 7 (25° C.).

3. The composition of claim 1, wherein the organic or inorganic salt is selected from the group of alkali metal salts of carboxylic acids.

4. The composition of claim 1, wherein R is selected from the group consisting of methyl and phenyl.

5. The composition of claim 1, wherein Ar is represented by the following formula (III): ##STR00016## wherein W is selected from the group consisting of a single bond, an oxygen atom, a carbonyl group, a sulfur atom, a SO.sub.2 group, a divalent C1-C20 aliphatic radical and a divalent C5-C20 cycloaliphatic radical and V shall represent the substituent groups at the phenyl moieties which are independently selected from the group consisting of hydrogen, C1-C20 alkyl, C1-C20 alkoxy and halogen atoms, and/or Ar is selected from: ##STR00017##

6. A process for preparing polydiorganosiloxane-polyorgano block copolymers, wherein the process comprises reacting a composition according to claim 1 with a polymer selected from the group consisting of: polyester having repeating units consisting of the group of the general formulas: a) —[R.sup.2—C(═O)—O—].sub.x—, wherein x is at least 2, and R.sup.2 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, which are bound via a carbon atom to the adjacent carbonyl carbon atom, and b) —[R.sup.3—O—C(═O)—R.sup.4—C(═O)—O—].sub.x—, wherein x is at least 2, R.sup.3 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, and R.sup.4 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, which are bound via a carbon atom to the adjacent carbonyl carbon atom, polyetherimide (PEI), polyether ether ketone (PEEK), and polysulfone, and optionally one or more compounds selected from the group consisting of bisphenolic compounds, diorganocarbonates and organodiesters, optionally in the presence of a catalyst in a solventless melt at a temperature in the range of 160 and 400° C. with removal of the by-products by distillation.

7. The process according to claim 6, wherein En is hydrogen and wherein said composition is first reacted with diorganocarbonates and/or organodiesters to form linear carbonate-functional and/or ester-functional polydiorganosiloxanes, which are then reacted with the polymer.

8. The process of claim 6, wherein the polymer is selected from the group of oligomers of a polyester having repeating units consisting of the group of the general formulas: a) —[R.sup.2—C(═O)—O—].sub.x—, wherein x is at least 2, and R.sup.2 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, which are bound via a carbon atom to the adjacent carbonyl carbon atom, and b) —[R.sup.3—O—C(═O)—R.sup.4—C(═O)—O—].sub.x—, wherein x is at least 2, R.sup.3 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, and R.sup.4 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, which are bound via a carbon atom to the adjacent carbonyl carbon atom, a polysulfone, a polyetherimide and a polyether ether ketone represented by formulae (Va), (Vb), (Vc), (VI), (VII) and (VIII), respectively: ##STR00018## wherein each of Z, Z.sub.1, Z.sub.2, and Z.sub.3 is independently selected from divalent substituted or unsubstituted alkyl, aryl, and bisarylalkyl each having up to 30 carbon atoms, Q.sub.1 and Q.sub.2 are independently selected from the group consisting of hydrogen, and a —C(═O)—X group, wherein X is selected from the group consisting of hydroxy, alkyloxy, alkyl-substituted aryloxy, and aryloxy, each having up to 30 carbon atoms, and p is a number between 2 and 300.

9. The process of claim 6, further comprising mixing of component (A) and component (B) and optionally one or more polar organic compounds having up to 30 carbon atoms.

10. The process of claim 9, which comprises the step of first mixing of component (A) and component (B) and one or more polar organic compounds selected from the group consisting of saturated and unsaturated organic alcohols with on average up to 20 carbon atoms.

11. A polysiloxane-modified polymer, obtained by reacting at least one polymer selected from the group consisting of polyester having repeating units consisting of the group of the general formulas: a) —[R.sup.2—C(═O)—O—].sub.x—, wherein x is at least 2, and R.sup.2 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, which are bound via a carbon atom to the adjacent carbonyl carbon atom, and b) —[R.sup.3—O—C(═O)—R.sup.4—C(═O)—O—].sub.x—, wherein x is at least 2, R.sup.3 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, and R.sup.4 is independently selected from optionally substituted divalent organic residues having up to 30 carbon atoms, which are bound via a carbon atom to the adjacent carbonyl carbon atom, polyetherimides, polyether ether ketones, and polysulfones with the composition according to claim 1.

12. A process for the manufacture of the composition according to claim 1, which comprises the steps of: i) preparing component (A), ii) determination of the concentration of component (B) present after the preparation of component (A), iii) adjusting the concentration of component (B), optionally using a polar organic compound.

13. A process for the manufacture of the composition according to claim 1, which comprises the steps of: i) preparing component (A), ii) determination of the concentration of component (B) present after the preparation of component (A), iii) adjusting the concentration of component (B) using a polar organic compound, iv) applying heat and/or reduced pressure to obtain an intimate mixture.

14. The process according to claim 12, which comprises the step of mixing of component (A) and component (B) and one or more polar organic compounds selected from the group consisting of saturated and unsaturated organic alcohols with on average up to 20 carbon atoms.

Description

EXAMPLE 1

(1) To 20.1 kg of a linear hydroxyaryl-functional polysiloxane prepared according to Comparative Example A with a hydroxyl content of 14.3 mg KOH/g and an initial sodium content of 0.2 ppm (component (B)) was added 0.33 g of sodium benzoate as additional component (B). The polymer was heated with agitation to 95° C. until becoming clear, then cooled. The resulting polymer after addition of component (B) had a sodium content of 2.5 ppm (0.109 mmol/kg).

(2) Reaction of the above polysiloxane polymer (A) containing the sodium benzoate (B) with the polycarbonate polymer used in comparative example A and TPPP under conditions identical to those in Comparative Example A, gave a white silicone-polycarbonate block copolymer with an eta rel solution viscosity of 1.377. The block copolymer was found to have excellent melt stability, as indicated in Table 2, whereby the polymer molecular weight as indicated by the MVR value was unchanged after 20 minutes at 300° C. The block copolymer was also found to have good solvent resistance and hydrolysis resistance. The block copolymer structure was found to be uniform according to atomic force microscopy with an average polysiloxane domain size of less than 1 micron. Extraction of the copolymer as in Example A found <15% unbound polysiloxane. Also the Charpy-notched impact test at 10° C. of a 3 mm bar was unchanged, and still ductile, after ageing at 85° C. and 85% relative humidity for 300 hours.

EXAMPLE 2

(3) To a linear hydroxyaryl-functional polysiloxane prepared according to Comparative Example A with a hydroxyl content of 14.3 mg KOH/g was added sodium acetate to achieve a sodium content of 1.3 ppm (0.06 mmol/kg). Reaction of this polysiloxane polymer containing sodium acetate with the polycarbonate of Comparative Example A and TPPP under conditions identical to those in Example 1 gave a silicone-polycarbonate block copolymer with an eta rel solution viscosity of 1.38, a MVR value at 300° C. (ISO 1133) of 8.33. The block copolymer was found to have excellent melt stability as indicated in Table 2. The copolymer was found to have a tensile strength of 59 N/mm.sup.2, an elongation at break of 106%, a Vicat temperature (B50: 50 N/50° K/h) of 146° C., as well as good solvent resistance and hydrolysis resistance. The block copolymer structure was found to be uniform according to atomic force microscopy with an average siloxane domain size of less than 1 micron. The block copolymer was found to have good low temperature impact resistance as indicated by an Izod notched impact test value (ISO 180/1A) of 50 kJ/m.sup.2 (ductil, 10/10 samples) at −50° C.

COMPARATIVE EXAMPLE B

(4) To 180 g of a linear hydroxyaryl-functional polysiloxane (A) prepared according to Comparative Example A with a hydroxyl content of 14.3 mg KOH/g and an initial sodium content of 0.2 ppm was added 0.45 g of sodium benzoate and 50 g of mixed xylenes. The polymer solution was heated to 120° C. and vacuum stripped to remove the xylene, becoming clear. The resulting polymer upon cooling was turbid and had a sodium content of 310 ppm (13.5 mmol/kg component (B)).

(5) Reaction of the above polysiloxane polymer containing sodium benzoate with the oligomeric polycarbonate of Comparative example A and TPPP under conditions identical to those in Example 1 gave an inhomogeneous, highly crosslinked copolymer that was largely insoluble.

EXAMPLE 3

(6) To a linear hydroxyaryl-functional polysiloxane (A) prepared according to Comparative Example A was added the organic and inorganic salts (B) of Table 1 and then reacted with polycarbonate oligomer of Comparative Example A and TPPP under conditions identical to those in Example 1. The resulting polysiloxane-polyorgano block copolymers had the properties in Table 1.

(7) TABLE-US-00001 TABLE 1 OH- Initial Number Component (B) Added Component Copolymer mg Content Component (B) (C) eta rel. Copolymer Example KOH/g [mmol/kg] (B) [mmol/kg] viscosity Appearance Comp. 11.9 0.004 None 0.004 1.28  Inhomogeneous Exp. A Comp. 14.3 0.004 Sodium 13.5 n.m. Inhomogeneous, Exp. B Acetate crosslinked 1 14.3 0.008 Sodium 0.109 1.377 Homogeneous Benzoate 2 14.3 0.008 Sodium 0.06 1.380 Homogeneous Acetate 3a 15.6 0.004 Na 4- 0.13 1.358 Homogeneous Methoxy- Benzoic Acid 3b 15.6 0.004 Na 3-Methyl- 0.13 1.398 Homogeneous Benzoic Acid 3c 15.6 0.004 Sodium 0.13 1.373 Homogeneous Oleate

(8) TABLE-US-00002 TABLE 2 MVR Added MVR 300° C. Exam- OH- Compo- Comp. B 300° C. 20 min- ple Number nent (B) mmol/kg initial utes Comment 1 14.3 Sodium 0.109 10.7 10.8 Stable at Benzoate 85° C. and 85% rH for 300 h 2 14.3 Sodium 0.06 8.33 8.36 Acetate
If higher levels of the component (B) are used in the polysiloxanes (A) and admixed with the polymers to be modified then the resulting polydiorganosiloxane-polyorgano block copolymers are colored, and can exhibit high levels of crosslinking. If the salt, the component (B) at concentration level according to the invention, is added directly into a mixture of the polymer then the resulting reaction mixture does not exhibit the inventive higher reactivity.