Abstract:
The present invention belongs to the field of surface modification of solid materials, specifically relates to a method of changing the surface wettability of polymer materials. The method of the present invention comprises of rubbing the surface of the polymer materials various times by using sand paper of different grades (GB/T 15305) with a determined pressure at the ambient temperature, so as to change the contact angle of said surface of polymer material with water thereby changing the surface wettability of the polymer materials to different degrees. The method of the present invention has advantages of using devices that are simple, low cost, and the surface characteristics of the polymer materials could be changed from hydrophilicity to hydrophobicity, from hydrophobicity to super hydrophobicity, or from hydrophilicity to super hydrophilicity, at ambient temperature without any special requirement to the polymer materials or the preparation process thereof.

Description:
CROSS-REFERENCE TO OTHER APPLICATIONS 
   This is a National Phase of International Application No. PCT/CN2004/001384, filed on Nov. 30, 2004, which claims priority from Chinese Patent Application No. 200410004721.6 filed on Feb. 24, 2004. 
   FIELD OF THE INVENTION 
   The present invention belongs to the field of surface modification of solid materials, specifically pertains to a method of changing the surface wettability of polymer materials. 
   BACKGROUND OF THE INVENTION 
   Solid surface modification, a well-studied area in surface chemistry and interface engineering, is showing promise in being applied broadly in industry and daily life. The surface property of a solid can be changed after modification of the surface and a series of properties such as absorption, wettability, dispersion, etc. Among the above surface properties of a solid, wettability is of great importance. Wettability is mainly determined by two indispensable factors: the chemical property and the geometrical morphology. The wettability of the solid surface can be changed by changing its roughness. 
   Currently in this art, there are a variety of methods for modifying the surface of the polymer materials, which may be generally classified as chemical and physical modification methods. 
   (1) Dipping Modification 
   In this method, the surface property of the polymer materials is improved by dipping the polymer materials into a treatment solution for oxidization. The disadvantages of using particular treatment solutions include the short life span of such solutions and sometimes repeated dipping. 
   (2) Photochemical Modification 
   In this method, the wettability and stickiness of the surface of the polymer materials can be improved through a chemical change induced by the exposure to ultraviolet irradiation. 
   (3) Surface Graft Modification In this method, plasma, an ultraviolet or chemical agent is used to generate grafting sites on the surface of the polymer materials; then the polymer materials are placed into monomers for grafting. 
   (4) Radiation Modification 
   In this method, the polymer materials are subjected to ionization, excitation and the generation of free radicals caused by the radiation in order to break bonds and make cross-links, or the generated free radicals polymerize with other monomers to achieve a surface modification. 
   (5) Coating Method 
   In this method, the surface property of the polymer materials is improved by coating some inorganic oxides thereon at a low temperature through a vacuum deposition process. 
   (6) Plasma Surface Modification 
   In this method, a large amount of active particles contained in the plasma such as electron, ions, and atoms and molecules in the excited state act on the surface of the polymer materials to induce complex physical and chemical changes causing etching, cracking and polymerizing, and generating a large quantity of free radicals or some polar groups; thus improving the surface property of the polymer materials. The plasma surface modification is advantageous in that only the superficial surface layer of the materials is modified without changing the main body and various surfaces can be modified by using suitable kinds of plasma gases. However, it is disadvantageous in that the degrading effectiveness of plasma exists. 
   The above methods have main drawbacks as follows during changing of surface wettability of polymer materials: 
   (1) Wastes are produced, which will pollute the environment, during the chemical modification process; 
   (2) Radioactive pollutions exist during the radiation modification process; 
   (3) The vacuum evaporation and plasma surface modification need expensive devices and have a complex operation process. 
   SUMMARY OF THE INVENTION 
   The objective of the present invention is to provide a method of changing the surface wettability of polymer materials with a process that is simple, highly effective, low cost, easy to operate, and friendly to the environment. 
   The method of the present invention comprise of rubbing the surface of the polymer materials in various using sand paper of different grades (GB/T 15305) with a given pressure at the ambient temperature, so as to change the contact angle of said surface of polymer material with water to change the surface wettability of the polymer materials to different degrees. 
   When the grade of the sand paper is #80, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #100, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #120, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #180, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #240, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #300, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #360, the pressure is 4000 to 7000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #500, the pressure is 7000 to 8000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #600, the pressure is 7000 to 8000 Pa and the rubbing times are 5 to 10; 
   When the grade of the sand paper is #1200, the pressure is 8000 to 9000 Pa and the rubbing times are 5 to 20; 
   When the grade of the sand paper is #1500, the pressure is 8000 to 9000 Pa and the rubbing times are 5 to 2°. 
   According to the present invention, the change of the contact angle of the polymer materials surface with water is 10° to 50° by changing the grade of the sand paper, the pressure, and the rubbing times. 
   The polymer substrate is selected from polycarbonate substrate, polymethyl methacrylate substrate, polystyrene substrate, polytetrafluoroethylene substrate, polyvinyl alcohol substrate and the like. 
   The method of the present invention has advantages that the devices required by the method are simple, the cost is low, the process is easy to operate and the surface characteristics of the polymer materials can be changed from hydrophilicity to hydrophobicity, from hydrophobicity to super hydrophobicity, or from hydrophilicity to super hydrophilicity, even at ambient temperature without any special requirement to the polymer materials or the preparation process thereof. For example, the surface characteristics of polycarbonate substrate, polymethyl methacrylate substrate and polystyrene substrate can be changed from hydrophilicity to hydrophobicity by rubbing, and the surface characteristic of polytetrafluoroethylene substrate can be changed from hydrophilicity to super hydrophilicity by rubbing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1A  is an image showing the contact angle of the polymer surface with water before rubbing according to Example 50 of the present invention. 
       FIG. 1B  is an image showing the contact angle of the polymer surface with water after rubbing according to Example 50 of the present invention. 
       FIG. 2A  is an image showing the contact angle of the polymer surface with water before rubbing according to Example 57 of the present invention. 
       FIG. 2B  is an image showing the contact angle of the polymer surface with water after rubbing according to Example 57 of the present invention. 
       FIG. 3A  is an image showing the contact angle of the polymer surface with water before rubbing according to Example 60 of the present invention. 
       FIG. 3B  is an image showing the contact angle of the polymer surface with water after rubbing according to Example 60 of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Hereinafter, the present invention will be described in detail with reference to the following examples. 
   EXAMPLE 1 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #80 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 116°. 
   EXAMPLE 2 
   The surface of polycarbonate substrate was rubbed back and forth 8 times by using a #80 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 122°. 
   EXAMPLE 3 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #80 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 120°. 
   EXAMPLE 4 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #80 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 103°. 
   EXAMPLE 5 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 8 times by using a #80 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 109°. 
   EXAMPLE 6 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #80 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 105°. 
   EXAMPLE 7 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #80 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 107°. 
   EXAMPLE 8 
   The surface of polystyrene substrate was rubbed back and forth 8 times by using a #80 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 113°. 
   EXAMPLE 9 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #80 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 110°. 
   EXAMPLE 10 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #80 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 112°. 
   EXAMPLE 11 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #80 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 114.5°. 
   EXAMPLE 12 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #80 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 119°. 
   EXAMPLE 13 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #80 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 40°. 
   EXAMPLE 14 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #80 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 33°. 
   EXAMPLE 15 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #80 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 37°. 
   EXAMPLE 16 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #100 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 123°. 
   EXAMPLE 17 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #100 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 129°. 
   EXAMPLE 18 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #100 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 125°. 
   EXAMPLE 19 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #100 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 117°. 
   EXAMPLE 20 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #100 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 113°. 
   EXAMPLE 21 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #100 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 120°. 
   EXAMPLE 22 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #100 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 123°. 
   EXAMPLE 23 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #100 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 131.2°. 
   EXAMPLE 24 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #100 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 135.1°. 
   EXAMPLE 25 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #100 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 128.5°. 
   EXAMPLE 26 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #100 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 26°. 
   EXAMPLE 27 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #100 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 34°. 
   EXAMPLE 28 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #120 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 124°. 
   EXAMPLE 29 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #120 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 130°. 
   EXAMPLE 30 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #120 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 121°. 
   EXAMPLE 31 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #120 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 127°. 
   EXAMPLE 32 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #120 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 135°. 
   EXAMPLE 33 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #120 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 130°. 
   EXAMPLE 34 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #120 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 133°. 
   EXAMPLE 35 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #120 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 137°. 
   EXAMPLE 36 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #120 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 131°. 
   EXAMPLE 37 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #120 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 33°. 
   EXAMPLE 38 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #120 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 23°. 
   EXAMPLE 39 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #180 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 124°. 
   EXAMPLE 40 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #180 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 120°. 
   EXAMPLE 41 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #180 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 115°. 
   EXAMPLE 42 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #180 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 110°. 
   EXAMPLE 43 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #180 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 137°. 
   EXAMPLE 44 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #180 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 132°. 
   EXAMPLE 45 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #180 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 139°. 
   EXAMPLE 46 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #180 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 143°. 
   EXAMPLE 47 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #180 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 140°. 
   EXAMPLE 48 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #180 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 24°. 
   EXAMPLE 49 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #180 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 14°. 
   EXAMPLE 50 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #240 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 136° as shown in  FIGS. 1A and 1B . 
   EXAMPLE 51 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #240 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 130°. 
   EXAMPLE 52 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #240 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 131°. 
   EXAMPLE 53 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #240 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 135°. 
   EXAMPLE 54 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #240 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 140°. 
   EXAMPLE 55 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #240 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 134°. 
   EXAMPLE 56 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #240 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 150°. 
   EXAMPLE 57 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #240 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 160° as shown in  FIGS. 2A and 2B . 
   EXAMPLE 58 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #240 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 156°. 
   EXAMPLE 59 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #240 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 15°. 
   EXAMPLE 60 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #240 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 5° as shown in  FIGS. 3A and 3B . 
   EXAMPLE 61 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #300 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 134°. 
   EXAMPLE 62 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #300 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 130°. 
   EXAMPLE 63 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #300 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 137°. 
   EXAMPLE 64 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #300 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 132°. 
   EXAMPLE 65 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #300 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 134°. 
   EXAMPLE 66 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #300 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 137°. 
   EXAMPLE 67 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #300 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 140°. 
   EXAMPLE 68 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #300 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 144°. 
   EXAMPLE 69 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #300 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 149°. 
   EXAMPLE 70 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #300 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 29°. 
   EXAMPLE 71 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #300 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 11°. 
   EXAMPLE 72 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #360 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 131°. 
   EXAMPLE 73 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #360 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 125°. 
   EXAMPLE 74 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #360 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 127°. 
   EXAMPLE 75 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #360 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 121°. 
   EXAMPLE 76 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #360 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 131°. 
   EXAMPLE 77 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #360 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 121°. 
   EXAMPLE 78 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #360 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 140°. 
   EXAMPLE 79 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 8 times by using a #360 sand paper with a pressure of 5700 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 142°. 
   EXAMPLE 81 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #360 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 134°. 
   EXAMPLE 82 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #360 sand paper with a pressure of 4000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 34°. 
   EXAMPLE 83 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #360 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 17°. 
   EXAMPLE 84 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #500 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 118°. 
   EXAMPLE 85 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 115°. 
   EXAMPLE 86 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #500 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 109°. 
   EXAMPLE 87 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 114°. 
   EXAMPLE 88 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #500 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 107°. 
   EXAMPLE 89 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 113°. 
   EXAMPLE 90 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #500 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 131°. 
   EXAMPLE 91 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5-times by using a #500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 126°. 
   EXAMPLE 92 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #500 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 21°. 
   EXAMPLE 93 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 31°. 
   EXAMPLE 94 
   The surface of polycarbonate substrate was rubbed back and forth 10 times by using a #600 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 119°. 
   EXAMPLE 95 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #600 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 115°. 
   EXAMPLE 96 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 10 times by using a #600 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 110°. 
   EXAMPLE 97 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #600 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 104°. 
   EXAMPLE 98 
   The surface of polystyrene substrate was rubbed back and forth 10 times by using a #600 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 114°. 
   EXAMPLE 99 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #600 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 107°. 
   EXAMPLE 100 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 10 times by using a #600 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 133°. 
   EXAMPLE 101 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #600 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 126°. 
   EXAMPLE 102 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 10 times by using a #600 sand paper with a pressure of 7000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 34°. 
   EXAMPLE 103 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #600 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 24°. 
   EXAMPLE 104 
   The surface of polycarbonate substrate was rubbed back and forth 20 times by using a #1200 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 108°. 
   EXAMPLE 105 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #1200 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 102°. 
   EXAMPLE 106 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 20 times by using a #1200 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 97°. 
   EXAMPLE 107 
   The surface of polymethyl methacrylatesubstrate was rubbed back and forth 5 times by using a #1200 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 91°. 
   EXAMPLE 108 
   The surface of polystyrene substrate was rubbed back and forth 20 times by using a #1200 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 101°. 
   EXAMPLE 109 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #1200 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 94°. 
   EXAMPLE 110 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 20 times by using a #1200 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 111°. 
   EXAMPLE 111 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #1200 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 109°. 
   EXAMPLE 112 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 20 times by using a #1200 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 31°. 
   EXAMPLE 113 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #1200 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 41°. 
   EXAMPLE 114 
   The surface of polycarbonate substrate was rubbed back and forth 20 times by using a #1500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 95°. 
   EXAMPLE 115 
   The surface of polycarbonate substrate was rubbed back and forth 5 times by using a #1500 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 86° to 90°. 
   EXAMPLE 116 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 20 times by using a #1500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 92°. 
   EXAMPLE 117 
   The surface of polymethyl methacrylate substrate was rubbed back and forth 5 times by using a #1500 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 75° to 85°. 
   EXAMPLE 118 
   The surface of polystyrene substrate was rubbed back and forth 20 times by using a #1500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 93°. 
   EXAMPLE 119 
   The surface of polystyrene substrate was rubbed back and forth 5 times by using a #1500 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 78° to 90°. 
   EXAMPLE 120 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 20 times by using a #1500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 106°. 
   EXAMPLE 121 
   The surface of polytetrafluoroethylene substrate was rubbed back and forth 5 times by using a #1500 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 108° to 101°. 
   EXAMPLE 122 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 20 times by using a #1500 sand paper with a pressure of 8000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 40°. 
   EXAMPLE 123 
   The surface of polyvinyl alcohol substrate was rubbed back and forth 5 times by using a #1500 sand paper with a pressure of 9000 Pa at the ambient temperature, so as to change the surface contact angle from 45° to 53°.