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600聚氨酯密封膠

聚氨酯密封膠是以聚氨酯橡膠及聚氨酯預(yù)聚體為主要成分的密封膠。此類密封膠具有高的拉伸強(qiáng)度、優(yōu)良的彈性、耐磨性、耐油性和耐寒性，但耐水性特別是耐堿水性欠佳。它可分為加熱硫化型、室溫硫化型和熱熔型三種，其中室溫硫化型又有單組分和雙組分之分。
Polyurethane sealant is a kind of sealant with polyurethane rubber and polyurethane prepolymer as the main component. This kind of sealant has high tensile strength, good elasticity, abrasion resistance, oil resistance and cold resistance, but water resistance, especially alkali resistance, is poor. It can be divided into three types: heating vulcanization type, room temperature vulcanization type and hot melt type. Among them, room temperature vulcanization has one component and two components.
聚氨酯密封膠的應(yīng)用及常識

Application and common sense of polyurethane sealant
聚氨酯密封膠是以聚氨酯橡膠及聚氨酯預(yù)聚體為主要成分的密封膠。此類密封膠具有高的拉伸強(qiáng)度、優(yōu)良的彈性、耐磨性、耐油性和耐寒性，但耐水性特別是耐堿水性欠佳。它可分為加熱硫化型、室溫硫化型和熱熔型三種，其中室溫硫化型又有單組分和雙組分之分。
Polyurethane sealant is a kind of sealant with polyurethane rubber and polyurethane prepolymer as the main component. This kind of sealant has high tensile strength, good elasticity, abrasion resistance, oil resistance and cold resistance, but water resistance, especially alkali resistance, is poor. It can be divided into three types: heating vulcanization type, room temperature vulcanization type and hot melt type. Among them, room temperature vulcanization has one component and two components.
聚氨酯密封膠廣泛用于建筑物、廣場、公路作為嵌縫密封材料，以及汽車制造、玻璃安裝、電子灌裝、潛艇和火箭等的密封。
Polyurethane sealant is widely used in buildings, squares, roads as caulking sealing materials, sealing and automobile manufacturing, installation of glass, electronic filling, submarines and the rockets.
聚氨酯密封膠有如下特點(diǎn)：優(yōu)良的耐磨性、低溫柔軟性以及性能可調(diào)節(jié)范圍較廣、機(jī)械強(qiáng)度大、粘接性好、彈性好，并且具有優(yōu)良的復(fù)原性，可適合于動態(tài)接縫，耐候性好，使用壽命可達(dá)15~20年，耐油性能優(yōu)良，耐生物老化性好且價(jià)格適中。
Polyurethane sealant has the following characteristics: excellent abrasion resistance, low temperature flexibility and performance can be adjusted in a wide range, high mechanical strength, good adhesion, good elasticity, and has excellent resilience, can be suitable for the dynamic joint, good weather resistance, service life can reach 15~20 years, excellent oil resistance, resistance to biological aging is good and the price is moderate.
但是聚氨酯密封膠也有一些缺點(diǎn)如：不能長期耐熱，淺色配方容易受紫外光老化，單組分膠貯存穩(wěn)定性受包裝及外界影響較大，通常固化較慢，高溫?zé)岘h(huán)境下可能產(chǎn)生氣泡和裂紋。
But polyurethane sealant also has some disadvantages, such as: not long term heat resistance, light color formula is susceptible to ultraviolet light aging, the stability of single component gel storage is affected by packaging and the outside world, usually slow curing, high temperature environment may produce bubbles and cracks.