用于制作复合材料的材料?

用于制作复合材料的材料?

Polyester Resins

Polyester resins are a family of polymers used to produce a broad range of products. Thermoset polyesters are known as unsaturated polyester resins. They are available in a number of formulations for specific applications. These formulations are usually designated by the principle raw material that determines the performance characteristics of the resulting polymer backbone. Common unsaturated polyester resin formulations include:

I. Orthophthalic
II. Terephthalic
III.Isophthalic
IV. Dicyclopentadiene(DCPD)
五. Chlorendic
VI. Bisphenol A Fumarate Polyesters
VII.Vinyl ester

On the most basic level these resins consist of an unsaturated polyester polymer dissolved in a crosslinking monomer and various additives that compromise a “resin system”. Technically, polyester resin is the product of reacting an unsaturated dibasic acid, 通常是恶藻, 与甘氨酸. 树脂的特征通过添加饱和的二丁酸，例如直智赤赤酸酯, 异戊酸或脂肪酸.

聚酯树脂系统

聚酯骨架 (寄生虫, 同一, ETC。) 与交联的单体结合在一起，以常用液体形式创建树脂. 使用最广泛的单体是苯乙烯. 其他常见的单体包括: 甲基丙烯酸酯 (MMA), 乙烯基甲基烯 (VT), α甲基苯乙烯 (AMS), para甲基苯乙烯 (PMS), 和邻苯二甲酸酯 (DAP). 这些通常与苯乙烯结合使用以优化属性. 继续探索其他单体以最大程度地减少环境影响.

抑制剂 - 由于不饱和聚酯抑制剂的倾向. Inhibitors slow the curing reaction by reacting with free-radicals before they cause crosslinking between the polymer and the monomer.Common inhibitors include Quinones (HQ, MTBHQ, PBQ, or THQ) and p-tert-butylcatechol (TBC).

Promoters – Sometimes referred to as accelerators, these materials facilitate effective room temperature curing . The promoter reacts with the initiator at the time of molding. Promoters include cobalt compounds, used with MEKP initiators; and aniline compounds, used for co-promoters in a MEKP system and as the primary promoter in ambient conditions with BPO initiators. Polyester resins are available in pre-promoted form, where the resin manufacturer includes the promoter in the product; or in unpromoted formulations where the molder adds promoter prior to processing.

Initiators – Sometimes incorrectly referred to as catalyst. When added to polyester resin the initiator reacts with the resin and decomposes, forming free radical molecules. These free radicals overcome the inhibitor and begin a cascading polymerization reaction, also known as curing.

Functional additives – Resin characteristics and performance can be modified with the addition of a number of additives. These include: Fire retardant additives, thixotropes, pigments, vapor suppressants, and other additives.

Product Resins

Isophthalic Polyester Resin

Isophthalic polyester resins are a broad class of resins formulated from isophthalic acid, glycols, and maleic anhydride. The specific resin specification is selected to impart desired properties and corrosion resistance. These resins can be used for moderate corrosion resistance applications to a temperature range around 180° F. Isophthalic resins exhibit good resistance to water, acids, weak bases, and hydrocarbons such as gasoline and oil.

Vinyl Ester Resin

Technically vinyl ester resins are a polyester resin, however they are normally classified separately from polyesters due to their enhanced mechanical properties and corrosion resistance. Bisphenol A based epoxy vinyl ester resins are methacrylated epoxy polyesters The Novolac epoxy vinyl ester resins enhance the epoxy component resulting in higher performance. Vinyl esters offer enhanced strength and generally better impact and thermal shock resistance than polyester resins. While the standard epoxy vinyl ester resins are limited to 220 – 250° F in most applications, 具有高密度交联的其他版本适用于高于250°F的温度. 这些树脂对酸具有极高的耐药性, 碱, 次氯酸盐, 和许多溶剂.

双苯酚A富马酸聚酯树脂

双苯酚A富马酸聚酯树脂是通过与丙烷氧化物和富马酸反应的反应，使其对碱环境特别抗性的树脂提供. 该树脂主要用于涉及热苛性溶液的应用. 它适用于酸的服务, 选定的有机溶剂和盐溶液的温度范围约为250°F.

氯伦敦聚酯树脂

氯化树脂不饱和, 卤代聚酯树脂. 它们特别适合在升高温度或高度氧化环境中运行的设备，例如Hot, wet chlorine. These resins are particularly well suited for chimney liners, flue gas duct, chrome plating tanks, pickling tanks, and chlorine headers.

Phenolic Resins

The phenolic polymer represents one of the earliest commercialized thermoset resins and first appeared in the late 1800’s. Phenolic resins are formed by the reaction of phenol and formaldehyde It is typically a heat cured thermoset. There are two types of phenolic resins – resole (one-step) and novolac (two-step). Resoles are base-catalyzed thermosetting resins that are self-crosslinking. Novolacs are catalyzed with acids and require a hexamine crosslinker to become thermosetting. Phenolics offer high temperature resistance; excellent resistance to chlorinated solvents and salt water; excellent fire/smoke properties.

Furan Resin or Furfural Alcohol Resin

呋喃树脂也称为呋喃醇树脂基于呋喃醇的聚合物衍生物. 这些树脂与典型的聚酯或乙烯基酯树脂不同，因为它们使用树脂制造商提供的特殊酸催化剂混合物固化. 由于需要不同的预防措施. 树脂还通过冷凝反应固化，这意味着在树脂固化后脱水. 这些树脂必须缓慢固化，以避免在树脂加热期间分层. 这些聚合物对浓碱和含有氯化有机物的酸具有极佳的抗性，并且优于溶剂抗性中的聚酯和环氧乙烯基酯. Because of this Furfural alcohol resins are used to make chemical storage tanks when vinyl ester resins or polyester resins can not be used. These resins are suitable for use up to about 250° F for many corrosive applications. Furfural alcohol based resin is not suitable for oxidizing chemicals and is not be used in environments containing chromic or nitric acids, peroxides or hypochlorites.

Epoxy Resins

Epoxy resins are very similar to vinyl esters. 然而, while a polyester resin has double carbon to carbon bond sites, epoxies are characterized by the presence of an epoxy group (a three member ring, two carbon and one oxygen). There is another difference between epoxies and polyesters that involves the number of active sites along the polymer backbone. In epoxy resins, 这些位点仅在每个聚合物或分支链的末端找到, 沿聚合物链中的聚酯主链中的碳碳双键发生了很多次. 环氧树脂提供出色的纤维粘结 (矩阵至纤维) 提高抗压强度, 弯曲强度, 增加层间剪切 ,并增强韧性 (提高影响力, 更好的伤害容忍度).

产品增援

加固材料 与多种形式的聚合物矩阵系统结合使用，以创建用于腐蚀应用中的层压板. 不同形式的加固已适应了特定的过程方法, 或该方法是围绕加固类型构建的. 有两个主要的纤维用作腐蚀行业提供的复合材料的增援: 玻璃纤维和碳.

玻璃纤维

连续玻璃丝是通过在铂/菱形衬套上通过数千个孔绘制熔融玻璃而形成的 (5 至 25 微米), 淬灭, 大小, 并陷入任何一个 102 或者 204 细丝. 尺寸充当耦合剂，将树脂粘结到树脂浸渍过程中.

腐蚀应用中使用的典型玻璃制剂:

电子玻璃 - (石灰铝硼酸盐) 是复合材料行业中最常用的加固，因为它具有良好的强度特性, 抵抗水降解和相对成本.
S玻璃 - 高力量
C玻璃 - 耐腐蚀

碳

碳纤维由有机前体制成, 包括锅 (聚丙烯硝基烯), 人造丝, 和俯仰. PAN是商业上可用的纤维, 螺距是煤焦油或石油蒸馏的残留物. 它必须在制造碳纤维之前形成纤维. 使适合在腐蚀复合材料制造的碳纤维的过程始于纤维的“稳定”. 抽出锅或螺距纤维, 在张力下通过加热空气 (400ºF至750ºF). 这个过程交联并重新排列纤维，因此它们不会在随后的处理中融化. 然后将材料经过更高的温度 (900ºF - 2700ºF) 在氮气中称为碳化或热载阶段, 仍然处于紧张状态. 纤维, 仍处于紧张状态和氮气中, 受到更高的温度 (3600ºF - 6000ºF) 在石墨阶段. 最后, 将纤维在电解浴中清洗, 然后大小 (与聚合物矩阵相兼容的聚合物饰面) 应用, 干并缠绕到线轴上.

碳纤维提供了所有钢筋纤维的最高强度和刚度. 高温性能对于碳纤维特别出色. 基于锅的纤维的主要缺点是它们的高相对成本, 这是基础材料成本和能源密集型制造过程的结果.

纺织品

加固对最终产品性能的重要性对于复合制造商来说至关重要. 这些纺织品的特性在制造过程的选择中也起着非常重要的作用. Products that may yield very good properties for a hand lay-up product may not be suitable for vacuum infusion, but readily adaptable to RTM.

There are numerous types and forms of reinforcements used in the fabrication of composites. Some are available direct from the fiber producers, others are converted from basic fiber to specialized products by textile manufacturers. The properties exhibited by these various forms of reinforcement will depend upon many factors. These factors may include the type of weave, the weights of the fibers per area, the thickness of the fabric, thread count, fiber diameter, and type of fiber.

Woven Reinforcements

Woven composite reinforcements are woven on a loom with the fibers typically aligned in the machine direction (warp). The weaving, 经线纤维的上外自动以相对较高的速度自动完成. 这种交叉纤维的编织称为填充. 如果使用额外的编织，将纤维切下45º, 它被称为偏见.

编织的复合钢筋通常属于布或编织巡游类别. 布重较轻, 通常来自 6 至 10 每平方码盎司. 这是用于大型结构的最常见的加固类型，因为它具有相当重的重量 (24 每平方码盎司是最常见的), 这可以快速积累厚度. 纺织品织工开发了为复合材料制造提供所需特征的产品. 开放度是指平行纤维之间的空间, and is a measure of the tightness of the weave. It is inversely related to warp and fill counts. The drape of a reinforcement refers to how well the material conforms to the shape of the mold. These and other characteristics are dependant not only upon the fiber properties, but also on the method of which they are woven.

Knitted Reinforcements

Knitted fabrics are woven reinforcements in which the warp and fill fibers are looped to create a fabric with high drape and conformability. These reinforcements provide greater strength and stiffness per unit thickness as compared to woven roving.

Chopped Strand Mat and Chop Reinforcements

Mat reinforcements are roll stock products used in hand lay-up fabrication. Chopped strand mat consists of randomly oriented glass fiber strands 1 至 2 inches in length that are held together with a styrene soluble binder. Continuous strand mat is similar to chopped strand mat, except that the fiber is continuous and laid down in a swirl pattern. Both hand lay-up and spray-up produce plies with equal physical properties. This is a very economical way to build up thickness, especially with complex molds.

Continuous Roving Reinforcement

Glass fibers used for continuous roving generally range in diameter from 0.00035” to 0.00090” (9 至 23 微米). They start as molten glass (2500°F). These fibers are pulled thru platinum bushings at very high speeds (200 mph) There may be as many as 4,000 of these tiny fibers to make one filament. These filaments are then gathered into bundles, called strands. They are held together with a special binder or sizing.

多端rov绳由许多单独的链组成，可以切碎并随机沉积到树脂基质中. 工艺，例如喷涂板成型化合物, 执行多端巡游. 细丝缠绕和裁缝也可以使用多端roving.

利用单向加固的过程，例如灯丝绕组或裁缝. 该产品由许多单独的细丝组成一条链.

其他腐蚀材料

表面面纱

面纱是一种轻巧的非编织面料，用于制造纤维增强塑料. 非织造面纱 (也称为垫子或组织) 通常用于在复合罐中制造腐蚀屏障, 管道, 管道, 流感堆栈, 配件, 和泵/阀门. 非织造面纱通常由C玻璃纤维制成, 碳或其他合成纤维.

面纱的使用抑制了复合表面中的微裂缝的产生. 对于高腐蚀性环境, 这些面纱通常由C玻璃或碳纤维制成.

面纱可以为FRP部分提供以下特征或特性:

改善表面外观和轮廓
改善耐腐蚀性和使用寿命
改善耐磨性和冲击阻力
改善热冲击性能
改善染料的磨损和减少的拉力拉力拉力
防止底层风化的FRP零件盛开到表面
用作基础增援部队的印刷障碍物
提供电导率

碳面纱

碳面纱可提高化学稳定性, 还具有导电性的额外好处. 碳面纱用于接地, 为了最大程度地减少静电的积累. 静态耗散在处理爆炸性液体和气体的复合罐和管道中尤其重要.

内核

三明治复合材料由放置在两个复合层之间的非常轻的材料组成. 中心中的材料称为核心, 而复合层称为皮肤. 在三明治建筑中 (核心材料在每一侧都有加固的玻璃/树脂皮肤) 提供更大的机械强度和刚度, 磅重, 比任何其他结构选择, 不管使用的材料如何. 更远, 各种各样可用的核心材料类型, 从巴尔萨到泡沫再到蜂窝, 提供广泛的材料密度, 几何, 处理选项, 成本和物理属性.

有四种在腐蚀应用中广泛使用的基本核心材料: 末端谷物巴尔萨, 苯乙烯丙烯腈 (圣) 泡沫, 聚氯乙烯 (PVC) 泡沫和聚对苯二甲酸 (宠物) 泡沫. 末端晶粒balsa之所以受欢迎，是因为它便宜，并且由于其最终晶粒的“蜂窝”结构提供了强大的机械性能Balsa的机械性能主要来自其末端粒结构. 由SAN和PVC制成的核心比Balsa密集 (关于 4 lb/ft³), 但是往往更昂贵. SAN和PVC都是提供结构支持的热固性配方. PET作为结构性泡沫需要稍高的密度，以匹配SAN和PVC的机械强度和刚度, 和匹配balsa的密度要高得多.

一些核心材料提供更好的机械性能, 但是为刀片增加额外费用. 有经济的核心材料缺乏机械强度. 这些变量需要深入审查零件性能的规格和要求. 核心材料也可以是特定过程的, 例如, 蜂窝不适合输液.