FUNCTIONALIZED PARTICLES

Abstract

Functionalized particles comprising a shell and a core and a payload that is embedded or entrapped, wherein the shell matrix is obtained by interfacial polymerisation of vinyltriethoxy silane and at least one other ethylenically unsaturated monomer copolymerizable with vinyltriethoxy silane, said functionalized particles being capable to chemically bind to a substrate, are suitable as controlled release systems for textile applications to impart durable softness and excellent water retention even after multiple laundries.

Claims

1. Functionalized particles comprising a shell and a core and a payload that is embedded or entrapped, wherein the shell comprises a matrix obtained by interfacial polymerisation of vinyltriethoxy silane and at least one other ethylenically unsaturated monomer copolymerizable with vinyltriethoxy silane, said functionalized particles being capable to chemically bind to a substrate.

2. Functionalized particles according to claim 1, wherein the at least one other ethylenically unsaturated monomer is a hydrophobic monomer.

3. Functionalized particles according to claim 2, wherein the at least one other ethylenically unsaturated hydrophobic monomer is styrene or glycidyl methacrylate.

4. Functionalized particles according to claim 2, wherein the at least one other ethylenically unsaturated hydrophobic monomer is styrene and glycidyl methacrylate.

5. Functionalized particles according to claim 1, wherein the payload is a silicone softener.

6. Functionalized particles according to claim 1, wherein the payload is chemically bonded to the matrix of the functionalized particle.

7. A process for the preparation of the functionalized particles according to claim 1, which process comprises the steps of preparing an oil-in-water dispersion and causing polymerisation of vinyltriethoxy silane and at least one other ethylenically unsaturated monomer copolymerizable with vinyltriethoxy silane at the oil-water interface in the presence of the payload.

8. A process for the preparation of a substrate modified with functionalized particles, comprising treating the substrate with the functionalized particles according to claim 1 to chemically bind the functionalized particles to the substrate.

9. The process according to claim 8, wherein the substrate is a fiber material containing hydroxyl groups or containing nitrogen.

10. The process according to claim 9, wherein the fiber material is cellulose containing textile fiber material.

11. A substrate modified with functionalized particles obtained according to the process of claim 8.

Description

PREPARATION EXAMPLE 1

[0061] 64.3 g of a suitable silicone softener (containing 30.89 gm of active silicone content), 0.64 g polysorbate 80 and 25 g of deionized water are added to a 3 neck-glass reactor equipped with a condenser, a thermometer an agitator and a dropping funnel. The mixture is stirred at 350 rpm for 10 to 15 minutes and nitrogen is purged through the mixture. Then 0.42 g of 2,2′-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride are added to the mixture under stirring at room temperature. The temperature of the mixture is slowly raised to 35 to 40° C. within 10 to 15 minutes and maintained at this temperature. Subsequently, 1.55 g of vinyl triethoxysilane, 1.55 g of glycidyl methacrylate and 5.79 g of styrene are added to the reaction mixture at 35 to 40° C. under stirring. After the addition of the monomers is completed the temperature of the reaction mixture is increased to 50 to 55° C. and stirring is continued for 4 h under a nitrogen atmosphere. Afterwards the reaction mixture is allowed to cool to 25 to 35° C. The concentration of unreacted monomer is verified by GC and HPLC. The content of residual unreacted styrene is below 0.09%. Afterwards water is added to adjust the desired solid content of 35 to 38%. The dispersion of the functionalized particles thus obtained shows a good shelf life even upon prolonged storage at 40° C.

APPLICATION EXAMPLE 1

[0062] A cotton fabric/towel is passed through padding mangle to wet the fabric/towel with water. Subsequently, the wet fabric/towel is passed through 1-liter application bath prepared using 50 g of encapsulated silicone softener obtained in accordance with Preparation Example 1 and 10 g of UVITEX® BST LIQ. The pH of application bath is adjusted to 5.5 using acetic acid. The pick-up of the cotton fabric/towel is 15±2%. The treated wet cotton fabric/towel is dried and cured at 120±5° C. for 10 minutes. After drying and curing the fabric is tumble dried for 20 minutes with hot air of a temperature of 45° C. The fabric/towel thus treated is kept for conditioning at 25±5° C. for 1 day.

[0063] The treated fabric/towels are tested for initial and 10 Home Laundering (HL). Washing is done as per European 7A Home Laundering method. Initial softness, softness upon washing and water retention of treated towel are recorded after conditioning. Water retention in % is determined according to ASTMD 4772. An untreated fabric/terry towel ideally has a water retention of about 70%.

[0064] The fabric/towel treated in accordance with Application Example 1 shows a good softness/handle even after 10 home laundries and an initial water retention of 55±5%.

EXAMPLES 2 TO 6 (PREPARATION AND APPLICATION)

[0065] Following a procedure analogous to that described in Example 1, but using the monomers given in Table 1 there are obtained the functionalized particles of Examples 2 to 6 with the properties given in Table 1.

TABLE-US-00001 TABLE 1 Monomer concentration [wt %] Shelf Glycidyl Monomer/ life Water Handle Vinyltriethoxy meth- Vinyl silicone Initiator at retention after Ex Styrene silane acrylate pyrrolidone ratio [wt %]** 40° C. [%] 10 HL 2 9.3 4.68 4.68 1:2 0.9 yes 12 yes 3 5 2.5 1 1:2 0.5 yes 30 yes 4 5 2.5 1 1   1:2.3 0.5 yes 10 yes 5 7.5 2 2 1.6:1   0.5 yes 48 yes 6* 7.4 1.96 1.96 1.5:1   0.5 yes 46 yes *Example 6 contains in addition to the other monomers 1 wt % of acrylic acid and 0.01 wt % of 3-(trimethoxysilyl)propyl methacrylate. **[wt %] is based on the total weight of the emulsion applied for preparation of the functionalized particles.

[0066] The fabric/towels treated in accordance with Examples 2 to 6 show a good softness/handle even after 10 home laundries and a good water retention.