METHOD TO IMPROVE THE SURFACE MODIFICATION BY USING ALKYLBORANES

Abstract

Process for the modification of a surface of a solid substrate comprising treatment of the surface with (i) a solution comprising an organoborane-amine complex and a polymer and subsequently with (ii) a polymerizable compound (herein referred to as monomer) and optionally a deblocking agent

Claims

1. A process for modifying surface of a solid substrate, the process comprising treating the surface with (i) a solution comprising an organoborane-amine complex and a polymer and, subsequently, (ii) a polymerizable compound and, optionally, a deblocking agent.

2. The process of claim 1, wherein the organoborane-amine complex has a structure of formula (I)
R.sub.1R.sub.2R.sub.3BNR.sub.4R.sub.5R.sub.6(1), wherein R.sub.1, R.sub.2 and R.sub.3 are each independently an alkyl group, a cycloalkyl group, an alkyl or cycloalkyl group substituted with a heteroatom, an alkylamino group, an aryl group, a heteroaryl group, an alkoxy group or an aryloxy group, with the proviso that at least one of R.sub.1, R.sub.2 and R.sub.3 is an alkyl or aryl group, and R.sub.4, R.sub.5 and R.sub.6 are each independently hydrogen, an alkyl group, a cycloalkyl group, a substituted alkyl group, an alkoxy group, an alkylamino group, an aryl group or a heteroaryl group, with the proviso that not more than two of R.sub.4, R.sub.5 and R.sub.6 are simultaneously hydrogen, or NR.sub.4R.sub.5R.sub.6 is a heterocyclic aliphatic or aromatic amine, optionally comprising at least one heteroatom selected from the group consisting of N, O, S and P.

3. The process of claim 1, wherein the organoborane-amine complex is a trialkylborane-amine complex.

4. The process of claim 1, wherein the polymer is a polyalkylenoxide, a polyalkyleneglycol, a polycaprolactone, a polyvinyllactone, a polyvinyllactame or a mixture thereof.

5. The process of claim 1, wherein the polymer is a polyethyleneglycol or a polyvinylpyrrollidone.

6. The process of claim 1, wherein the solution in (i) comprises 0.1 to 50% by weight of the polymer.

7. The process of claim 1, wherein the polymerizable compound is a radically polymerizable monomer of formula (II)
R.sub.7R.sub.8CCR.sub.9R.sub.10(II), or of formula (III)
R.sub.7CCR.sub.8(III), or of formula (IV)
R.sub.7R.sub.8CO(IV), or of formula (V)
R.sub.7R.sub.8CNR.sub.9(V), wherein R.sub.7, R.sub.8, R.sub.9 and R.sub.10 are each independently hydrogen, an alkyl group, a cycloalkyl group, a substituted alkyl group, an aralkyl group, an alkaryl group, an alkoxy group, an alkylamino group, an aryl group, a heteroaryl group, a carbonyl group, a carboxyl group, an amide group, a carboxylic ester group or a nitrile group, or the polymerizable compound is a mixture of radically polymerizable monomers comprising at least one of the radically polyermizable monomers of formulae (II) to (V).

8. The process of claim 1, wherein the polymerizable compound comprises an acrylic or methacrylic group or comprises a mixture of monomers comprising at least 50% by weight of monomers with an acrylic or methacrylic group.

9. The process of claim 1, wherein the deblocking agent is a mineral acid or an organic acid.

10. The process of claim 1, wherein the surface is a polymer surface selected from the group consisting of a polydimethylsiloxane (PDMS), a polyethylene (PE), a polypropylene (PP), a polytetrafluorethylene (PTFE) a polystyrene (PS), a blend thereof and a blend comprising a blend thereof in an total amount of at least 50% by weight.

11. The process of claim 1, wherein the surface is a polypropylene surface.

Description

EXAMPLES

[0081] A) Materials used:

[0082] Polymer film:

Isotactic polypropylene (PP), 0.05 mm thick

[0083] borane-amine complexes used:

[0084] tri-sec-butylborane-diaminopropane (TsBB-DAP), formula:

##STR00001##

and
tri-n-butylborane-1-methoxypropylamin-3 (TnBB-MOPA)
and
tri-ethylborane-diaminopropane (TEB-DAP) polymers used:
the following Polyvinylpyrrolidone (PVP) trade products have been used:
Luvitec K90 from BASF having a weight average molecular weight of 1.400.000 g PVP k360 from Sigma-Aldrich which having a weight average molecular weight of 360.000 g Luvitec K30 from BASF having a weight average molecular weight of 50.000 g

[0085] As vinylpyrrolidone copolymer Sokalan HP 56 which is a vinylpyrrolidone/vinylimidazole copolymer (Mw 70.000) has been used.

[0086] As polyethylenglycol PEG k20 from Sigma-Aldrich has been used, which has a (Mw of 20.000).

[0087] As polyalkylencopolymer Plurionic F 127 has been used, which is a triblock copolymer of polyethylenglycol and polypropyleneglycol: PEG-PPG-PEG

[0088] Solution of the borane-amine complex and polymer

[0089] The solution was prepared by adding the borane-amine complex and the polymer to a solvent; the solvent was isopropylalcohol (IPA), water or dioxolane as listed in table 1.

[0090] Monomers and monomer solution

[0091] The following monomers have been used:

2-Hydroxyethyl methacrylate (HEMA)
[2-(Methacryloyloxy)ethyl]trimethylammonium chloride (QAEMA)
Metharcylic acid (AAc)

[0092] Formulas:

##STR00002##

[0093] The monomer solution used in the examples consisted of:

19 volume % HEMA
19 volume % QAEMA
2 volume % AAc and
60 volume % H.sub.2O

[0094] B) Test procedure for the examples

[0095] The procedure was been performed at room temperature (about 25 C.)

[0096] A 12 cm12 cm Polypropylene (PP) film is been fixed in a plastic frame. Dirt and dust has been removed with compressed air. 10 milliliters (ml) of the alkylborane solution (AB) were poured on the PP film. After 5 minutes the solution was removed by hanging the PP film vertically for an interval of 1 min to 30 min.

[0097] Then, 10 ml of the above monomer solution were given on the PP film. After 30 minutes the monomer solution was removed. The coated PP film solution was soaked in deionized water for an hour. Thereafter the coated PP film was washed and rubbed film physically with hand to remove excess polymer, which was not bonded to the surface. The coated was kept vertically and dried at room temperature (under air) for 24 hours.

[0098] C) Results

[0099] The quality of the coatings obtained on the PP films was judged, results of this optical judgement are shown in the table 2:

none means that no polymer or only small amounts of polymer were grafted to the surface and hence only small areas, if any, were covered with polymer
poor means that the grafted polymer did not cover the surface homogeneously
good means that the grafted polymer did cover the surface homogeneously with minor deficiencies, only
excellent means that the grafted polymer did cover the surface homogeneously without or nearly without deficiencies

[0100] Furthermore the increase of weight of the PP films was determined and the grafting efficiency determined according to the following formula:

Grafting efficiency=weight gained/surface area100% (mg/cm2)

TABLE-US-00001 TABLE 1 solutions of the organoborane-amine complex organoborane-amine complex, volume % polymer, % by based on total solution solvent weight in solution Comparison TsBBDAP, 20% IPA None example Example 1 TsBBDAP, 20% IPA PVP (360k), 10% Example 2 TsBBDAP, 20% IPA PVP (360k), 15% Example 3 TsBBDAP, 20% IPA PVP (360k), 20% Example 4 TsBBDAP, 20% IPA PVP (360k), 30% Example 5 TsBBDAP, 20% IPA PVP (K90), 10% Example 6 TsBBDAP, 20% IPA PVP K30, 1% Example 7 TsBBDAP, 20% IPA PVP K30, 2% Example 8 TsBBDAP, 20% IPA PVP K30, 5% Example 9 TsBBDAP, 20% IPA PVP K30, 10% Example 10 TsBBDAP, 20% IPA PVP K30, 15% Example 11 TsBBDAP, 20% IPA PVP k30, 20% Example 12 TsBBDAP, 20% IPA PVP (30, 30% Example 13 TsBBDAP, 20% IPA PVP k30, 35% Example 14 TsBBDAP, 20% IPA PVP k30, 40% Example 15 TsBBDAP, 20% H2O PVP K30, 10% Example 16 TsBBDAP, 20% IPA Sokalan HP 56, 1% Example 17 TsBBDAP, 20% IPA Sokalan HP 56, 5% Example 18 TsBBDAP, 20% IPA Sokalan HP 56, 10% Example 19 TsBBDAP, 20% IPA Sokalan HP 56, 20% Example 20 TsBBDAP, 20% dioxolane PEG 20k, 0.5% Example 21 TsBBDAP, 20% dioxolane PEG 20k, 1% Example 22 TsBBDAP, 20% dioxolane PEG 20k, 5% Example 23 TsBBDAP, 20% dioxolane PEG 20k, 10% Example 24 TsBBDAP, 20% dioxolane PEG 20k, 20% Example 25 TsBBDAP, 20% dioxolane PEG 20k, 30% Example 26 TsBBDAP, 20% dioxolane PEG 20k, 35% Example 27 TsBBDAP, 20% dioxolane PEG 20k, 40% Example 28 TsBBDAP, 20% THF Pluronic F127, 1% Example 29 TsBBDAP, 20% THF Pluronic F127, 5% Example 30 TsBBDAP, 20% THF Pluronic F127, 10% Example 31 TsBBDAP, 20% THF Pluronic F127, 20% (not fully dissolved)

TABLE-US-00002 TABLE 2 characteristics of the modified surface obtained Optical Grafting efficiency judgement mg/cm.sup.2 Comparison None 0 example Example 1 good 1.11 Example 2 Poor 0.09 Example 3 Poor 0.43 Example 4 Poor 0.35 Example 5 Poor 0.58 Example 6 Poor 0.15 Example 7 Poor 0.35 Example 8 good 0.75 Example 9 Excellent 0.84 Example 10 Excellent 1.01 Example 11 good 1.11 Example 12 good 1.35 Example 13 good 1.30 Example 14 good 1.21 Example 15 Poor 0.18 Example 16 Poor 0.15 Example 17 Excellent 1.09 Example 18 Excellent 0.91 Example 19 good 0.33 Example 20 Poor 0.31 Example 21 Excellent 0.4 Example 22 Excellent 1.05 Example 23 Excellent 1.17 Example 24 Excellent 1.00 Example 25 Good 0.83 Example 26 good 0.78 Example 27 poor 0.57 Example 28 Excellent 1.43 Example 29 Good 0.65 Example 30 Good 0.77 Example 31 Poor 0.34