Surface modification of silicones

Abstract

A process for modifying a silicone elastomeric-based surface of a textile article where the coefficient of friction (COF) of the silicone elastomeric-based surface is generally reduced by at least 5% is disclosed. The process comprises subjecting the silicone elastomeric-based surface of the textile article to vacuum ultraviolet (UV) radiation.

Claims

1. A process for modifying a silicone elastomeric-based surface of a textile article, said process comprising: subjecting the silicone elastomeric-based surface of the textile article to vacuum ultraviolet radiation; wherein the vacuum ultraviolet radiation is performed using a low-pressure mercury lamp; and wherein the coefficient of friction of the silicone elastomeric-based surface is reduced by at least 5%.

2. The process according to claim 1, wherein the silicone elastomeric-based surface of the textile article consists of silicone elastomer.

3. The process according to claim 2, wherein the silicone elastomer is the reaction product of a hydrosilylation or peroxide cure of an alkenyl-functional organopolysiloxane and a SiH functional organopolysiloxane.

4. The process according to claim 1, wherein the textile article is an airbag.

5. The process according to claim 1, wherein the textile article is a silicone elastomer coated airbag.

6. The process according to claim 1, wherein the textile article is coated, and is subsequently subjected to vacuum ultraviolet radiation.

7. The process according to claim 1, wherein the vacuum ultraviolet radiation is performed on a conveyor belt.

8. A textile article having a silicone elastomeric-based surface, which surface is modified by the process according to claim 1.

9. The textile article according to claim 8, wherein the silicone elastomeric-based surface has a modified surface layer of less than 1 mm in thickness.

10. An airbag formed by the process according to claim 1.

11. A parachute formed by the process according to claim 1.

12. An outdoor textile formed by the process according to claim 1.

Description

EXAMPLES

(1) A 5 litre volume, one piece woven airbag, composed of 420 Denier polyester fibre was coated with commercial Dow Corning LCF 3760 at 60 +/5 grams per square meter on each side and cured for 1 minute at 190 C in a forced air oven.

(2) Irradiation of the test zones was carried out using a low pressure mercury lamp (wavelength 185 nm and 254 nm) of type Heraeus Noblelight, Soluva 4.20 VUV Modul (UV Intensity 140 mW/cm2, for a wave length of 254 nm, at distance of 10 mm; providing for an irradiation area of 230140 mm), for 2 minutes.

(3) Evaluation of the test zones was carried out with respect to airbag deployment (inflation duration-ASTM D6476), flex abrasion (ISO 5981), and coefficient of friction (ISO 8295). Test results are given in Table 1 below.

(4) TABLE-US-00001 TABLE 1 Deployment Coefficient (kPa; of Friction time to 50% of Flex Abrasion (Static/ Irradiation condition peak pressure) (Strokes; cycles) Dynamic) Control-no irradiation 7.5 seconds >1000 5.8/6.3 Treated zone, 2 4.5 seconds >1000 3.3/3.8 minutes irradiation

(5) Irradiation is shown to affect the airbags at the level of friction coefficient, reducing said parameter of more than 10%. Further, air permeation and fold resistance was shown to remain equivalent to that of the non-irradiated airbag pieces.