Polyester resinous fiber strengthens mechanism
Polyester colophony uses fibre glass to enhance what what get is a kind of composite material. It and divide evenly are qualitative metal, plastic wait for material to differ, from microcosmic on look, itself of this kind of composite material is complex structure. Its framework is fibre glass, matrix is colophony what form after solidify is plastic. Former it is inorganic silicate material, latter is high polymer material. Both performance side difference waits in mechanical, heat, chemistry very big. From this and formation structure, its eventually function depends on namely the function of oneself of two kinds of material and both the exterior coupling condition between. The function of two kinds of 1 material contrasts
On mechanical function fibrous intensity and stretch model quantity compare colophony to want a few times big, hot coefficient of expansion is small however much, other property is not same also.
Because the character of two kinds of material is different, in the complex structure of collective composition, the effect that they have also each are not identical. Its principle measures the colophony with inferior intensity to be matrix with inferior model namely, with higher standard quantity and relatively the fiber of high strenth increases. Matrix can produce plasticity to move below stress action, pass negative charge fiber to go up thereby, will shoulder load by fiber. Matrix makes fiber is stuck receive fixed, protect fiber, make be in steady state. Formed a kind of high strenth and the composite material that higher stretch standard measures so. The requirement of fiber and 2 pairs of colophony matrix
(1) serves as to the requirement fiber of fibre glass enhance material to should satisfy the following requirement. ① fiber is due higher stretch model volume. ② fiber is due higher ultimate strength. ③ is in a silk bundle in the intensity between each odd root fiber wants even, what lest arise,increase is inhomogenous, reduce the intensity of composite material. ④ is in operation treatment process, the protection with its due and good appearance, prevent fiber by abrade. ⑤ fibrous diameter should be stabilized equably, exterior position is good. (2) serves as the matrix of composite material to the requirement colophony of colophony matrix, should satisfy the following requirement. ① can fiber firm felt, can protect fiber, the process is made what make in composite material in not by abrade. ② can infiltration clearance of each odd root fiber, realize dispersive felt protection to fiber, prevent fiber surface to have space, the composite material that makes close-grained. Itself of ③ colophony matrix has certain model be out of shape ability, the stress in the composite material that can produce place of extra negative charge delivers fiber effectively to go up. Can long-term on chemistry look contains ④ and fiber, do not produce adverse reaction. ⑤ and fiber are in hot property is photogenic look, can develop the efficiency of two kinds of material reasonably. Two kinds of 3 interfaces of material
In colophony and fiber the felt that chemical stability and physical stability must have on the interface of two kinds of material, ability makes phase of two kinds of data is united in wedlock, develop oneself function, the composite material of generation. Coverture of fibre glass surface has a size, it is the main material that forms colophony and fiber interface. The action of size is protective fiber first, of the made working procedure after can be being passed withdraw solution, pool capital, twist, weaving and macerate treatment, do not send be worn away to rupture. For this, size should achieve two requirements; The fiber that is decentralize can be sticky synthesize; 2 it is to be able to infiltrate surface of each odd root fibrous, try to keep apart protection, prevent its mutual abrade or by treatment parts gall. This kind of size weighs spin size, in develop commonly used starch - oily water latex, emulsion of our country commonly used olefin. Size pulls the coverture when silk shapes in fibre glass on its, dry hind show successive coverture facing namely. Coupling agent is not contained commonly in this kind of size. And of size deleterious colophony and fiber interface stick receive, purify size wants when reason is used at enhancing colophony, again coverture is used with coupling agent ability. Use at enhancing resinous size to say to increase commonly model size, it is a kind of polymer (if get together ester of second acerbity ethylene) moisture prose style free from parallelism. Increase model size mixes action with coupling agent commonly, in fibre glass apparently the 4 % of 2 % ~ of the 2 % of 1 % ~ that deposition is fibre glass quality about or bulk. If be on fibre glass coverture is even, can increase fibre glass diameter to make an appointment with 1 % ~ 2 % , its ply is 0.1 ~ about 0.2μm. Increase model the coupling agent in size matchs 0.5 % commonly (quality mark) pH indicator aqueous solution or dispersive body are used, in size hydrolysis shrinks the get togethering that synthesizes low degree of polymerization silicon oxygen alkyl, the silicon alkyl that withholds a lot of active alcohol radical is round. Coupling agent is in fibre glass apparently a few minutes namely by adsorption, dry hind the coverture layer that forms ply of 0.005 ~ 0.05μm. Other thicker size grain adheres to namely the surface at coupling agent. Dry hind, partial size grain is direct adhere at fibre glass surface be in without coupling agent, the part is enclothed at coupling agent surface, have diffuse each other, formed the exterior structure of fibre glass so.
In colophony of fibre glass immerge, each constituent in exterior structure follows resinous solidify course and produce respective physico-chemical change. Colophony contains cross-linking agent, it is styrene commonly, still contain initator, still contain accelerant when room temperature shapes. These constituent and fibre glass are apparently original size constituent diffuses each other, form each constituent to mix exterior overburden of change, solidify hind is the interfacial area of colophony and fibre glass namely. If fibre glass undertakes coupling agent is handled again after size of purify of classics heat treatment, fibre glass surface changes vitreous coupling agent with glass only, coupling agent diffuses not easily with colophony happening. If fibre glass surface still is enclothed,have increase model size is other constituent (if get together second acerbity ethylene) when, diffuse each other with respect to meeting and colophony, be dissolved completely by colophony even, partial interface makes the resin that contains size, another part is produce tumid size by some of some constituent infiltration in colophony. The bulk mark of the size in the colophony of adjacent interface can amount to 5 % ~ 10 % . All sorts of chemistry on the interface happen to react on the foundation that above physics sex diffuses. First, incidental is coupling agent and polyester resinous reaction, this is generation composite material intensity and be able to bear or endure the significant response of ability in swimming. The cross-linking agent styrene in colophony besides undertaking cross-linking with polyester element catenary, still bolt with the Xi in coupling agent at the same time undertake cross-linking reacts. Right now, in coupling agent constituent if contain methylic propylene acyl when oxygen radical is round, the effect that its react effect comparing contains vinyl group is good, when reason polyester colophony and former union, the intensity of composite material and be able to bear or endure excel of ability in swimming and latter union. Some mix the constituent in other size in colophony constituent to attend solidify to react, some meetings withhold not deliquescent condition to enclothe on coupling agent, block coupling agent and colophony react, make composite material solidify shapes defer. Want to notice to choose fibre glass goods correctly in the production of glass reinforced plastics, want to notice the finishing condition of fibre glass especially. If choose undeserved, the likelihood causes glass reinforced plastics intensity and be able to bear or endure to drop of ability in swimming significantly, affect the fall of other performance characteristics further, accelerate the ageing process of goods. Be united in wedlock by distinct fibre glass size and polyester colophony, can produce the interfacial condition of different colophony and fibre glass, typical situation is like 4 kinds in graph 12-2. (A) forms chemical bond position by coupling agent cross-linking. (B) by close polyester colophony size (without coupling agent) adhere and formation physical adhere state. Be like 711 model size. (C) does not have any size, but rely on polyester colophony the adhere to fibre glass. If the fibre glass of size of heat treatment purify or water pull silk after fibre glass is dry namely dip polyester colophony. (D) keeps apart condition with what form when olefin emulsion coverture.
The condition that above differs 4 kinds produces distinct effect to the performance characteristics of goods of glass reinforced plastics. In process of polyester colophony solidify, because bulk is contractive, except (A) condition still can continue to maintain fibre glass and polyester colophony interface beyond good union, other 3 kinds of interfaces produce gap. Use close polyester colophony size to still can withhold the interface of adhere of one part physics; If use olefin emulsion to be in two-phase completely to keep apart condition, performance is poor. When the interface has interstitial presence, moisture issues infiltration interface in interstitial capillarity namely, have activator effect, the chemical bond that makes colophony weaker is slow rupture. When if stress is made,be being used, can rupture quickly. The chemical bond in this kind of weakness in polyester and coupling agent is silicon oxygen alkyl and ester key. Between fibre glass of consist in of silicon oxygen alkyl and interface of polyester resinous two-phase, also between consist in coupling agent and fibre glass surface. Ester bolts a catenary of element of resinous of consist in polyester on. The hydrolysis action of these chemical bond is reversible originally, can achieve proper balance; But in matrix of glass reinforced plastics, after hydrolysis broken paragraph be gotten on by the interface other material or stress space, make hydrolysis turns into not reversible, then fibre glass enhances the structure of polyester to be destroyed namely. 4 distinct size are right the influence of composite material functionDetermine from macroscopical and aspirant travel, can get the quantitative idea that distinct size affects to function of polyester glass reinforced plastics.
List two kinds of coupling agent undertake finishing to vitreous cloth (classics heat treatment) and the function that controls 307 polyester glass reinforced plastics respectively via the vitreous cloth of heat treatment only is comparative.
With A-151(vinyl 3 second oxygen base silicon alkyl) when processing, its do state flexural strength is compared only of heat treatment tall 15.2 % , curve a model the volume is high 21.4 % ; Soggy hind flexural strength and curve a model to measure reservation to lead latter of more remarkable excel. Although,Wo Lan handles flexural strength doing state with heat treatment close, but wet condition strength is apparent also excel is latter. The function of wet form of glass reinforced plastics that controls without the cloth of heat treatment glass of any size drops substantially.