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PBT具有以下特性:結(jié)晶速度快，可快速成型，吸水率低，電氣性能優(yōu)異且隨溫濕度變化小，耐候性好，適于戶外使用，且耐藥品性優(yōu)異，力學(xué)性能優(yōu)良。純PBT樹脂有優(yōu)異的沖擊韌性，但對缺口較刺激，經(jīng)玻纖增強后，不僅可使缺口刺激性得到改善，而且還能使熱變形溫度大大提高，彎曲模量成倍增長，突出的耐摩擦和耐磨耗特性，磨耗量比POM還小。PBT的缺點為:結(jié)晶收縮率大，尺寸穩(wěn)定性差。雖經(jīng)增強后可改善收縮率，但容易發(fā)生翹曲，同時使無缺口沖擊強度下降，對缺口刺激。由于PBT存在著這兩個突出缺點，因而限制了它的應(yīng)用。?（PBT has the following characteristics: fast crystallization speed, rapid molding, low water absorption, excellent electrical performance, small change with temperature and humidity, good weather resistance, suitable for outdoor use, excellent drug resistance and excellent mechanical properties. Pure PBT resin has excellent impact toughness, but it is sensitive to notch. After being reinforced by glass fiber, it can not only improve notch sensitivity, but also greatly increase the thermal deformation temperature, double the bending modulus, highlight the characteristics of friction and wear resistance, and the wear amount is smaller than that of POM. The disadvantages of PBT are: large crystallization shrinkage and poor dimensional stability. Although the shrinkage can be improved after reinforcement, it is prone to warpage, reduce the impact strength without notch and is sensitive to notch. Because PBT has these two prominent shortcomings, its application is limited.）