FORMULATION COMPRISING POLYMER PARTICLES AND A METHOD OF TREATING A SUBSTRATE WITH SAID FORMULATION IN A LIQUID MEDIUM

Abstract

A formulation comprising a multiplicity of solid polymer particles, wherein said polymer is selected from polyamide and polyester, wherein a polyalkylene glycol is covalently attached to said polymer at the surface of said polymer particles; and a method for treating a substrate comprising agitating the substrate with said formulation and a liquid medium, particularly wherein the method of treating is a laundry method.

Claims

1. A formulation comprising a multiplicity of solid polymer particles, wherein said polymer is selected from polyamide and polyester, wherein a polyalkylene glycol is covalently attached to said polymer at the surface of said polymer particles.

2. A formulation according to claim 1 wherein the polymer matrix of said polymer particles consists of monomeric repeating units linked by amide and/or ester linkages, wherein at least one terminus of at least one polymer chain is terminated by said covalently attached polyalkylene glycol at the surface of said polymer particles.

3. A formulation according to claim 1 wherein a polyalkylene glycol is covalently attached to said polymer at the surface of said polymer particles such that the polymer matrix of said polymer particles consists of monomeric repeating units linked by amide and/or ester linkages, wherein at least one terminus of at least one polymer chain is terminated by said covalently attached polyalkylene glycol at the surface of said polymer particles.

4. A formulation according to claim 1, 2 or 3 wherein the amount M.sub.PAG-S of covalently bound polyalkylene glycol at the surface is greater than the amount M.sub.PAG-I of covalently bound polyalkylene glycol inside the particle, preferably wherein the ratio M.sub.PAG-S:M.sub.PAG-I is at least 10:1.

5. A formulation according to any preceding claim wherein covalently bound polyalkylene glycol is not located inside the particle, preferably wherein polyalkylene glycol is not located inside the particle

6. A formulation according to any preceding claim wherein said polyalkylene glycol is covalently attached at the surface of said polymer particles via an ester bond.

7. A formulation according to any preceding claim wherein said polyalkylene glycol has formula HO(R.sup.1O).sub.nR.sup.2 and at least one terminus of at least one polymer chain of the polymer matrix of said polymer particles is terminated with an (CO)O(R.sup.1O).sub.nR.sup.2 group formed by the covalent attachment of said polyalkylene glycol at the surface of said polymer particles, wherein R.sup.1 is a divalent hydrocarbon group, R.sup.2 is H or a monovalent hydrocarbon group, and n is an integer of at least 1, preferably at least 5, and preferably no more than about 500.

8. A formulation according to any preceding claim wherein said polyalkylene glycol has formula HO(R.sup.1O).sub.nR.sup.2 wherein R.sup.1 is a divalent hydrocarbon group containing from 2 to 6 carbon atoms; and R.sup.2 is H or a monovalent hydrocarbon group containing from 1 to 30 carbon atoms, and n is an integer of at least 1, preferably at least 5, and preferably no more than about 500.

9. A formulation according to claim 7 or 8 wherein R.sup.1 is CH.sub.2CH.sub.2 or CH(CH.sub.3)CH.sub.2, and/or R.sup.2 is H, methyl, ethyl or propyl, and/or n=30 to 180.

10. A formulation according to any preceding claim wherein said polyalkylene glycol has a molecular weight M.sub.w from about 200 to about 10,000, more preferably from about 350 to about 8000, more preferably from about 600 to about 5000, particularly from about 900 to about 2000, and especially from about 1200 to about 1800 g/mol.

11. A formulation according to any preceding claim wherein said polyalkylene glycol is linear.

12. A formulation according to any preceding claim wherein the polyalkylene glycol is or comprises polyethylene glycol.

13. A formulation according to any preceding claim wherein said polymer is a thermoplastic polymer.

14. A formulation according to any preceding claim wherein said polymer is a polyamide.

15. A formulation according to any preceding claim wherein said polymer is or comprises an aliphatic or aromatic polyamide, preferably an aliphatic polyamide

16. A formulation according to any preceding claim wherein the polyamide is or comprises Nylon 4,6, Nylon 4,10, Nylon 5, Nylon 5,10, Nylon 6, Nylon 6,6, Nylon 6/6,6, Nylon 6,6/6,10, Nylon 6,10, Nylon 6,12, Nylon 7, Nylon 9, Nylon 10, Nylon 10,10, Nylon 11, Nylon 12, Nylon 12,12 and copolymers or blends thereof.

17. A formulation according to any preceding claim wherein the polyamide is or comprises Nylon 6, Nylon 6,6, Nylon 6,10 and copolymers or blends thereof.

18. A formulation according to any of claims 1 to 12 wherein said polymer is a polyester is selected from polyethylene terephthalate and polybutylene terephthalate.

19. A formulation according to any preceding claim wherein the particles comprise an inorganic filler.

20. A formulation according to any preceding claim wherein the particles have an average density of at least 1.25 g/cm.sup.3.

21. A formulation according to any preceding claim wherein the particles have an average particle size of from 1 to 20 mm.

22. A formulation according to any preceding claim wherein the particles are ellipsoidal, spherical, cylindrical or cuboid.

23. A formulation according to any preceding claim wherein said polyalkylene glycol is present in an amount of at least 1 wt % and/or no more than 15 wt % relative to the total weight of the particle.

24. A formulation according to any preceding claim which is a cleaning formulation.

25. A method for treating a substrate, the method comprising agitating the substrate with a formulation according to any of claims 1 to 24 and a liquid medium.

26. A method according to claim 25 wherein the particles are re-used in further treatment procedures according to the method.

27. A method according to claim 25 or 26 wherein the method is a method for treating multiple batches, wherein a batch comprises at least one substrate, the method comprising agitating a first batch with a formulation according to any one of claims 1 to 24 and a liquid medium, wherein said method further comprises the steps of: (a) recovering said particles; (b) agitating a second batch comprising at least one substrate and a formulation comprising the particles recovered from step (a) and a liquid medium; and (c) optionally repeating steps (a) and (b) for subsequent batch(es) comprising at least one substrate.

28. A method according to claim 25, 26 or 27 wherein the particles are re-used for at least 10, and preferably at least 100, treatment procedures according to the method.

29. A method according to any of claims 25 to 28 wherein the liquid medium is aqueous.

30. A method according to any one of claims 25 to 29 which is performed at a temperature of from 5 to 50 C.

31. A method according to any of claims 25 to 30 wherein the substrate is or comprises a textile.

32. A method according to claim 31 wherein the treating of said substrate is cleaning, coloration, bleaching, abrading or ageing, or other textile or garment finishing process.

33. A method according to any of claims 25 to 32 for cleaning a substrate which is or comprises a textile, the method comprising agitating the substrate with a cleaning formulation according to any of claims 1 to 24, and a liquid medium, and optionally a detergent composition.

34. A method according to claim 33 wherein the substrate is a soiled substrate.

35. A method according to claim 33 or 34 which is a method for cleaning multiple washloads, wherein a washload comprises at least one substrate which is or comprises a textile, the method comprising agitating a first washload with a cleaning formulation according to any of claims 1 to 24 and a liquid medium, wherein said method further comprises the steps of: (a) recovering said particles; (b) agitating a second washload comprising at least one substrate and a cleaning formulation comprising the particles recovered from step (a) and a liquid medium, wherein said substrate is or comprises a textile; and (c) optionally repeating steps (a) and (b) for subsequent washload(s) comprising at least one substrate which is or comprises a textile.

36. A method according to any of claims 25 to 30 wherein the substrate is or comprises an animal skin substrate.

37. A method according to claim 36 wherein the treating of an animal skin substrate is a tannery process.

38. A method of reducing the mechanical damage and/or shrinkage and/or colour fade of a substrate in a treatment process which comprises agitating the substrate with solid polymeric particles and a liquid medium, wherein the method comprises agitating said substrate with a formulation according to any of claims 1 to 24 and a liquid medium.

39. Use of a formulation according to any of claims 1 to 24 for treating a substrate.

40. Use of a formulation according to any of claims 1 to 24 for reducing the mechanical damage and/or shrinkage and/or colour fade of a substrate in a treatment process which comprises agitating the substrate with said formulation and a liquid medium.

41. A method according to claim 38 or 39 or a use according to claim 40 wherein said treating and said substrate are as defined in any of claims 25 to 37.

42. An apparatus suitable for performing the method of any one of claims 25 to 38 wherein the apparatus comprises a rotatable treatment chamber and one or more particle storage compartment(s) containing the particles as defined in any one of claims 1 to 24.

43. An apparatus according to claim 42 wherein the rotatable treatment chamber is a drum provided with perforations which allow the particles to exit the drum.

44. An apparatus according to claim 42 or 43 embodiment, the rotatable treatment chamber is a drum provided with lifters on the interior walls of the drum, optionally wherein the particles may exit the drum via said lifters, and wherein a lifter is defined as an elongated protrusion affixed perpendicularly to the inner walls of the drum.

45. An apparatus according to claim 42, 43 or 44 which additionally comprises a pump for transferring the particles into the treatment chamber.

46. An apparatus according to claim 42, 43 or 44 wherein the rotatable treatment chamber itself comprises one or more particle storage compartment(s).

47. An apparatus according to claim 46 wherein the particle storage compartment(s) is/are located in lifters which do not function as conduits to allow the particles to exit the treatment chamber.

48. A process for the manufacture of a solid particle comprising the steps of: (i) providing a solid polymer particle; and (ii) reacting said particle with a polyalkylene glycol such that said polyalkylene glycol becomes covalently attached to said polymer at the surface of said polymer particle, preferably wherein the reaction comprises acid hydrolysis conducted at a temperature of greater than 100 C., preferably in the presence of a catalyst, and preferably wherein the polyalkylene glycol is also the solvent for the reaction.

49. A process according to claim 48 wherein the polymer particle and the polyalkylene glycol are reacted in a ratio of from about 0.01 to about 1.5 moles polyalkylene glycol per kg of polymer particles.

50. A process according to claim 48 or 49 wherein the polyalkylene glycol and/or the polymer and/or the solid particle reaction product is as defined in any of claims 1 to 24.

51. A formulation according to any of claims 1 to 24 wherein said particle is prepared by a process comprising the steps of: (i) providing a solid polymer particle; and (ii) reacting said particle with a polyalkylene glycol such that said polyalkylene glycol becomes covalently attached to said polymer at the surface of said polymer particle, preferably wherein the reaction comprises a catalysed acid hydrolysis reaction, preferably wherein the reaction comprises a first acid hydrolysis stage and a second esterification stage.

Description

EXAMPLES

Example 1

[0135] Thermoplastic Nylon-6 cleaning particles (4.3 mm; filled with BaSO.sub.4 and having a density of 1.65 g/cm.sup.3) were used as the starting material. The particles were reacted with PEG-1500 by mixing 1 kg of the particles, 1.2 kg of PEG-1500, 3 ml of 95% sulfuric acid, 5 ml of titanium butoxide, and heating the mixture at 160 C. for 5-7 hours with stirring.

[0136] By removing 2-3 particles every hour and analysing them by Fourier Transform Infra-Red (FTIR) spectroscopy, the reaction was followed through the hydrolysis of the amide bond to carboxylic acid, to the formation of the ester bond between the acid group on the particle and the hydroxyl group of the PEG. The FTIR confirmed that PEG was covalently attached to the carboxylic acid through an ester bond by the appearance of a distinctive absorption band in the range of about 1715 to about 1735 cm.sup.1. The Nylon-6 particles used as the starting material contained no ester bonds present, and no peak in this area. FIG. 1 shows the difference between the starting material (1) and the PEGylated particles (2), which show the absorption band. FIG. 6 shows a photograph of the starting material (11) and the PEGylated particles (12, 13), wherein the PEGylated particle (13) is shown sliced in half.

[0137] X-Ray Photoelectron Spectroscopy (XPS) confirmed the presence of the ester bond in the reaction product, and quantified the amount of ester bonds as being 1.3% of the total bonds. The XPS results also demonstrated that the ratio of carbon to oxygen had changed significantly from the starting material to the PEGylated particles. It was found that the C:O ratio in the starting material is 5.8:1 while that in the PEGylated particles were 2.5:1.

Reference Example 1

[0138] A cleaning particle was prepared by co-extruding thermoplastic polyamide with polyether block polyamide in accordance with Example 4 of WO2017/017455. The cleaning particle also contained an inorganic mineral filler such that the weight ratio was 25:25:50 polyamide:polyether block polyamide:filler.

[0139] Performance in Cleaning Methods

[0140] The performance of the particles of Example 1 and Reference Example 1 was assessed in repeated cleaning tests using a Xeros washing apparatus as described in PCT patent publication WO 2011/098815. The conventional thermoplastic polyamide particles (i.e. the starting material noted above) were used as a Control.

[0141] The cleaning cycle was run at a temperature of 20 C. using 29.6 g detergent composition (Tide (US formulation); Proctor & Gamble). For each cleaning cycle, 4 kg of cleaning particles were used in each case. The liquid medium was water. The cleaning step of the cleaning cycle was run for 20 minutes. After the cleaning step, the wash load was rinsed and the washing apparatus performed a separation cycle for a period of 35 minutes (including rinse and separations steps). The total cycle time was about 55 minutes.

[0142] Each cleaning cycle was carried out using the garments shown in FIGS. 2A and 2B); identical garments were used for each particle type. The garment shown in FIG. 2A was selected in order to assess damage to transfers, i.e. where the design is not woven into the garment but attached to the surface of the fabric by adhesive as a sticker or transfer, which are commonly damaged in traditional washing machines. The polo shirt shown in FIG. 2B is a garment made from man-made-fibre which was known to shrink significantly during conventional wash cycles. These garments plus some additional polyester squares (to a total weight of 3.6 kg) were then washed in 10 cleaning cycles.

[0143] The washed garments were flat dried overnight and analysed in terms of length, width and colour after 2, 6 and 10 cycles.

[0144] A further wash performance test was conducted using the PEGylated particles of Example 1 after they had been run through accelerated ageing of 100 cycles, i.e. in this further test, the PEGylated particles experienced cleaning cycles 101 to 110.

[0145] Damage to the transfers on the garments was assessed visually and by touch. Shrinkage was measured with a tape measure and the measurement points are marked on the garment in permanent marker to ensure the same measurements are being taken every time.

[0146] The transfer of the garment washed using the PEGylated particles of Example 1 exhibited less damage, in terms of its visual appearance, compared to the transfer washed using the particles of Reference Example 1. In the touch test, the feel of the transfer washed by the PEGylated particles of Example 1 remained thick and sticky (in the same way as the unwashed garment), while the transfer washed by the particles of Reference Example 1 felt softer as if it has been worn down to the cotton underneath.

[0147] In order to assess the shrinkage of the polo shirt, the length and width were measured in multiple areas and the average is shown as bar chart in FIG. 3 (in which: C1 refers to the unmodified Control particles; E1 refers to the particles of Example 1; E1a refers to the particles of Example 1 after accelerated ageing for 100 cycles); and RE1 refers to Reference Example 1. FIGS. 4A and 4B demonstrate visually the difference in shrinkage of the garment washed for 10 cycles by the different particles, wherein garment (3) was washed by the unmodified Control particles; garment (4) was washed by the particles of Example 1; and garment (5) was washed by the particles of Example 1 after accelerated ageing (100 cycles).

[0148] The experiments demonstrate that the particles of Example 1, whether they are virgin particles or aged particles, surprisingly produce much lower shrinkage than the particles of Reference Example 1 or the Control example (unmodified). The unmodified particles of the Control experiment already provide lower shrinkage and comparable or superior cleaning performance in cleaning cycles as described above when compared to particle-free conventional washing machines.

[0149] The PEGylated particles of Example 1 were also analysed by FTIR spectroscopy immediately after the first 10 cycles of use and then again after they had been run through accelerated ageing of 100 cycles, and in each case, the same ester absorption band identified in the virgin PEGylated particles was clearly visible. The FTIR spectra presented in FIG. 5 show: the FTIR spectrum (6) of the unmodified particles (starting material); the FTIR spectrum (7) of the virgin PEGylated particles of Example 1; and the FTIR spectrum (8) of the aged PEGylated particles of Example 1 (110 cycles). The FTIR spectra clearly demonstrate the retention of the covalent bond between PEG and the polyamide upon repeated cleaning cycles.