GENİŞLEYEBİLEN POLİSTİREN KÖPÜK ÜRETİMİNDE KALIPLAMA PARAMETRELERİNİN TANE KAYNAMASI VE AĞIRLIĞA ETKİSİNİN İNCELENMESİ

Öz

Bu çalışmada, genişleyebilen polistiren (GPS) köpük üretiminde kalıplama basıncı ve sürelerinin kalıplama sonrası ağırlık değişimi ve tane kaynaması üzerine etkisi incelenmiştir. Deneysel çalışmalarda değişik kalıplama basıncı (1, 1,1 ve 1,2 atm) ve kalıplama süreleri (20, 30 ve 40 s)  kullanılarak ASTM D638 standardına göre polistiren numuneler üretilmiş ve bu numunelerin doğal yaşlandırması oda sıcaklığında 720 saat (30 gün) süre ile gerçekleştirilmiştir. Deneysel sonuçlar, polistiren köpük numunelerin doğal yaşlandırma işleminde ağırlık kaybının %99’nu 24 saat sürede gerçekleştirdiğini ve 720 saat sürede ise tamamlandığını göstermiştir. Kalıplama basıncı ve süresi arttıkça kalıplama sonrası ağırlık değişimleri azalmıştır. Polistiren köpük numunelerde 20 s kalıplama süresi 1 ve 1,1 atm kalıplama basınçlarında yeterli derecede tane kaynamasını sağlamazken 30 ve 40 s kalıplama süreleri yüksek derecede tane kaynaması üretmiştir. Kalıplama sonrası ağırlık değişimi arttıkça kaynama derecesinin düştüğü belirlenmiştir.

Anahtar Kelimeler

• GPS, Tane kaynaması, Kaybolan köpük

THE EFFECT OF MOLDING DENSITY ON THE BEAD FUSION AND WEIGHT IN THE EXPANDABLE POLYSTYRENE PRODUCTION

Abstract

In this study, the effect of molding times and pressures on weight change after molding and the bead fusion was investigated in the production of expandable polystyrene (EPS) foam. In experimental studies, polystyrene samples were produced using various molding pressures (1, 1.1 and 1.2 atm) and molding times (20, 30 and 40 sec) according to ASTM D638 standard and natural aging of these samples were carried out at room temperature for 720 hours (30 days). Experimental results showed that in the natural aging process of EPS foam 99% of losses of sample weight was performed approximately with 24 hours time, and was completed with 720 hours time. The weight change after molding was decreased with increasing molding pressure and time. While 20 sec molding time with the molding pressures of 1 and 1.1 atm did not provide sufficient bead fusion, the 30 and 40 sec molding times were produced high degree of bead fusion. It was determined that the fusion degree was decreased with increasing the weight change after molding.

Keywords

• EPS, Bead fusion, Lost foam

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