Spheriglass Solid Glass Microspheres Polyester Applications

Transcription

1 Spheriglass Solid Glass Microspheres Polyester Applications TECHNICAL AND ECONOMIC ADVANTAGES result from the inclusion of Spheriglass solid glass spheres in polyester resin mouldings. A series of laboratory studies has confirmed field reports that the addition of glass spheres, suitably treated for bonding to polyester resin, improves properties of gel coats, hand lay-up mouldings and gel coats. Benefits GEL COATS Increases abrasion and scratch resistance Reduces staining Reduces water absorption Lowers cost HAND LAY-UP Reduces Warpage Improves mechanical properties Eases wet-out of glass mat Lowers water absorption Reduces cost (above 40 PHR loading) CASTINGS Permits very high filler loading Reduces gel and cure time Lowers shrinkage uniformly Improves mechanical properties Reduces distortion Compared to other fillers: Easier to mix Higher concentrations possible Lower viscosity change Easier to de-aerate Easier to pour Much lower gel and cure time The incorporation of Spheriglass in a gel coat for "sanitary ware" (bathtubs, etc.) increased the abrasion (scrubbing) resistance and reduced the stain-ability, the water absorption and the cost. In hand lay-up mouldings consisting of glass fibre mat and polyester, Spheriglass improved most important mechanical properties, reduced water absorption, and extended resin while reducing the cost. Unfilled, Spheriglass filled, and calcium carbonate filled resins were compared. Spheriglass were more easily mixed into the resin than the calcium carbonate, and they increased the ability of the resin to wet out the fibreglass mat. Spheriglass filled laminates had less Warpage than those filled with calcium carbonate or unfilled. In another study comparing clay, calcium carbonate and glass spheres as fillers for polyester castings, it was found that mouldings containing the glass spheres had generally superior properties to castings of, the unfilled resins and castings filled with either clay or calcium carbonate. It was substantially easier to mix the spheres into the resin, and the viscosity change with increasing loading was at a much lower rate. 120 PHR of Spheriglass mixed into the resin readily, while 60 PHR of clay and 80 PHR of calcium carbonate were the extreme practical limits. The Spheriglass shortened the gel and cure times, while clay and calcium carbonate extended the gel and cure times. Higher concentrations of clay could not be cured. The shrinkage of the Spheriglass filled castings was more uniform and they were freer of distortion.

2 CASTING Spheriglass can be added to much higher levels, as much as 100%, versus clay and calcium carbonate. This advantage as shown by the reduced viscosity of Spheriglass filled systems allows a moulder to produce products that are of lower costs in a shorter preparation period. Spheriglass addition also improved the physical properties of the system. Spheriglass based systems outperformed other fillers in tensile, flexural and compressive strengths as well as water absorption and hardness. This give the moulder possibility to formulate better performances into his final products while minimising the amount of costly resin required. Uniformed shrinkage that resulted in less distortion of parts was also realised with Spheriglass. This allows a much higher degree of dimensional controls of parts leading to lower rejection rates and the ability to design larger and more complex products. Other fillers tested were less predictable Finally lower gel time and cure time of the resin mix was observed. This obvious saving time feature is directly transferable to improved productivity and lower production costs. Loading phr Viscosity of Polyester Casting Resin Glass Spheres VS Other Fillers Viscosity cps Spheriglass Clay Material Polyester Spheriglass Clay Mould Shrinkage Data Loading phr Shrinkage in/in Shrinkage % phr 40 phr 60 phr phr phr phr phr phr phr phr phr phr phr Did not cure - 80 phr Did not cure - Properties of Polyester Castings Property Resin Unfilled Spheriglass 3000 Microsphere Filler Filler Clay Filler 20 phr* 40phr 60phr 80phr 20phr 40phr 60phr 20phr 40phr 60phr 80phr Tensile Strength, psi (690) Tension Modulus, psi Elongation, % 6.47% 5.35% 1.96% 2.02% 1.79% 0.82% 1.16% 1.06% 1.57% 2.59% 2.4% 1.54% Flexural Strength, psi Compressive Strength, psi Water Absorption % 0.25% 0.17% 0.15% 0.12% 0.11 % 0.21% 0.24% 0.22% 0.17% 0.17% 0.18% 0.24% Hardness Rockwell M 67 M 82 M 85 M 84 M 85 M 79 M 79 M 80 M 65 M 44 M 14 M 10 Specific Gravity *phr = parts of additive by weight per 100 parts by weight of resin.

3 Gel and Exotherm Data for Polyester Resin Castings Filler Loading phr. Gel Time min Peak Temp. C Gel to Exotherm min. Cure Time min. Resin Spheriglass 3000, CP , Clay ч Required more than 6 hours to gel 2 Required more than 6 hours to harden HAND LAY-UP There are advantages in processing, physical properties and cost in the use of solid glass spheres in fibre glass matreinforced polyester hand lay-up laminates. Addition of Spheriglass to a 2-ply laminate brought distinct improvements in flexural strength, modulus, compressive strength, and resistance to water absorption as compared with the composite loaded with calcium carbonate or with unloaded resin. Spheriglass also improved mould flow and wet-out of the glass mat. High loadings are possible with this low-viscosity material. In addition, a better adhesion between the resin and mat should be realized. Finally, the physical properties of the system are improved. Spheriglass reduces shrinkage and distortion of the moulded part. Test panels of 0.09 m 2 with unfilled resin warped three to six times as much as the Spheriglass filled laminates. Calcium carbonate warped even more than the unfilled resin System d Unfilled resin: mm Spheriglass : to mm Calcium Carbonate: to mm

4 Physical Properties of Polyester Glass Mat Laminates Unfilled Resin With Spheriglass Filler With Filler Properties 20phr* 40phr 60phr 20phr 40phr 60phr Tensile Strength, psi Elongation, % Flexural Strength, psi 13,600 14,300 14,000 16,500 12,900 10,900 14,200 Flexural Modulus, psi Compressive Strength, psi Water Absorption, % in 24 hrs Rockwell Hardness M 86 M 99 M 95 M 95 M 76 M 82 M 82 Specific Gravity, g/cm * phr = parts of additive by weight per 100 parts by weight resin. This is based on the weight of the resin only. GEL COATS Spheriglass added to polyester gel coat improved the abrasion resistance by over 50% compared to other additives. In addition stain resistance overall was higher versus systems loaded with clay or calcium carbonate. Gloss retention was excellent with Spheriglass and translucency was substantially greater with Spheriglass than gel coats filled with calcium carbonate. Translucency of Gel Coat System "d" мм phr Spheriglass phr Spheriglass phr Spheriglass 8 20 phr 2 The greater the distance "d", the more the gel coat. translucent In a falling sand abrasion test, the spheres increased the abrasion resistance of the gel coat as much as 53 percent. Water absorption of the sanitary gel coat was reduced 32 percent by addition of 20 PHR of the glass spheres. Falling Sand Abrasion Resistance of Gel Coat Spheriglass, Loading phr 0 % Increase in Abrasion Resistance Spheres improved or equalled stain resistance of the gel coat except for lye and were equal or better than calcium carbonate with all staining agents tested. Water Absorption of a Sanitary Gel Coat 5,9 (1) Stain removed with tap water. % Absorption % Decrease 20 phr Spheriglass 4,0 32 Stain Resistance of Sanitary Gel Coat Staining Spheriglass CaCO 3 Agent 20 phr 20 phr Cola % Detergent Ammonia Coffee Shoe Polish Tea Ink Bleach % Lye Lipstick Black Crayon (2) Stain removed with 20 scrubbing cycles using isopropyl alcohol. (3) Stain removed after step 2 plus 20 cycles with scouring powder. (4) Stain removed after step 2 plus 60 cycles with scouring powder. (5) Stain was not removable. The calcium carbonate system is badly stained by ink and lye.

5 Coatings Interfacial Bonding, between the glass beads and the polymer can be enhanced by the use of a coupling agent (coating). Depending on the specific polymer being used Potters can provide you with the right coating for your application. For further information on coatings please refer to the specific datasheet.. Product/ Service Information Packaging: Spheriglass Solid Glass Microspheres are available in paper bags with plastic liners, bulk bags and various bulk shipping modes. Details of packaging options are available as a separate document. Samples in sufficient quantity for testing are available on request. Safety Information: Spheriglass Microspheres are moderately alkaline, and prolonged exposure may irritate the respiratory tract. In dusty environments, the use of a NIOSH-approved mask or respirator is recommended. Material Safety Data Sheets (MSDS) can be supplied on request. Other Product Range: Q-Cel Ultra-Light Weight Reducing Hollow Glass Microspheres Sphericel Ultra-Fine Hollow Glass Microspheres Spheriwhite Colour-Enhancing Solid Glass Microspheres Luxsil Cosmetic Microspheres Spacer Beads Solid Glass Microspheres for the bonding lines A & P series Technical Quality Solid Glass Microspheres Q-Cel ONG Hollow Microspheres for Oil Well Cementing For further information about our range of Solid & Hollow Glass Microspheres, please contact us: Potters Europe Information contained in this publication (and otherwise supplied to users) is based on our general experience and is given in good faith, but we are unable to accept the responsibility in respect of factors which are outside our knowledge or control. Potters Europe (EGM Division), Potters Hollow Spheres & Potters Europe are trading names of Potters Ballotini Limited Q-Cel, Sphericel, Spheriglass, Spheriwhite and Luxsil are registered trademarks of Potters Industries LLC. Pontefract Road Barnsley South Yorkshire S71 1EJ United Kingdom Phone: +44 (0) Fax: +44 (0) PQHS-Sales@pottersgroup.com Ref: