交聯(lián)聚乙烯電纜-10

1、交聯(lián)電纜交聯(lián)電纜苑會(huì)林北京化工大學(xué)交聯(lián)聚乙烯電纜的特點(diǎn)由于交聯(lián)聚乙烯為體型大分子,故為不熔不溶物,耐熱性明顯提高。交聯(lián)度低,軟化點(diǎn)變化不大;交聯(lián)度高,維卡耐熱溫度可提高30 40 ;交聯(lián)聚乙烯的長(zhǎng)期使用溫度為95 100 。交聯(lián)聚乙烯電纜的特點(diǎn)交聯(lián)聚乙烯結(jié)晶區(qū)減少,密度均勻,使其電絕緣性基本無(wú)變化,所以仍屬好的絕緣材料,并且絕緣性在較高溫度和苛刻的化學(xué)介質(zhì)中仍能保持高值,常用于電纜護(hù)套層。由于分子鏈間架起化學(xué)鏈橋,物理力學(xué)性能提高,特別是硬度、剛度、耐磨性、耐蠕變性和耐尺寸穩(wěn)定性;同時(shí)因?yàn)榻宦?lián)部分的分子鏈雖受限制,但還可在原位置附近作輕微振動(dòng)以消耗沖擊能,故沖擊強(qiáng)度也提高。交聯(lián)電纜的方法過氧化

2、物交聯(lián)硅烷交聯(lián)（一步法、兩步法）電子輻照交聯(lián)過氧化物交聯(lián)工藝DCP 用量與凝膠含量的關(guān)系試驗(yàn)基本配方為:PE 100 份; 抗氧劑1010 0.5份;DCP 0.63.0 份交聯(lián)溫度對(duì)凝膠含量的影響交聯(lián)溫度對(duì)凝膠含量的影響交聯(lián)溫度對(duì)凝膠含量的影響凝膠含量與材料力學(xué)性能的關(guān)系不同不同PEX 的電性能的電性能PEX-1 為一般的過氧化物交聯(lián)聚乙烯PEX-2 為加炭黑后的過氧化物交聯(lián)聚乙烯,炭黑本身有導(dǎo)電性,炭黑表面氧化程度高,其含氧基團(tuán)起絕緣作用,增加炭黑會(huì)使體積電阻率下降。PEX-3 為用作比較標(biāo)準(zhǔn)的意大利潘德那塑料公司生產(chǎn)的硅烷交聯(lián)聚乙烯,比較表中數(shù)據(jù)可以看出,一般的過氧化物交聯(lián)聚乙烯電性能較

3、高。炭黑含量對(duì)凝膠含量的影響炭黑含量對(duì)交聯(lián)聚乙烯拉伸強(qiáng)度的影響炭黑含量對(duì)交聯(lián)聚乙烯拉伸強(qiáng)度的影響ZnO 對(duì)交聯(lián)聚乙烯凝膠含量的影響ZnO 用量對(duì)交聯(lián)聚乙烯力學(xué)性能的影響抗氧劑對(duì)交聯(lián)聚乙烯的影響抗氧劑用量對(duì)交聯(lián)聚乙烯熱性能的影響交聯(lián)聚乙烯過氧化物交聯(lián)電纜料XL 07407Copolymer Wire and Cable CompoundDensity 1.40PETROTHENE XL 07407 is especially formulated for use in flame retardant primary insulation for low voltage automotive wi

4、re and cable (SAE J1128) applications and for UL applications including 125 appliance wire and SIS. XL 7407 is a non-tarnishing, non-halogenated, flame retardant, chemically crosslinkable compound. Non-discoloring antioxidant and special active peroxide have been added to ensure thermal stability du

5、ring processing and optimum curing results交聯(lián)硫化通道Petrothene XL 07407過氧化物可交聯(lián)無(wú)鹵阻燃聚乙烯電纜料加工應(yīng)用試驗(yàn)。擠出試驗(yàn)設(shè)備擠出試驗(yàn)設(shè)備：?jiǎn)温輻U擠出機(jī)3025，片材模具280(mmmm)。溫度設(shè)定： 模具80 100 110 120 110 擠出速度：1060轉(zhuǎn)分冷卻輥：三輥壓光機(jī)，壓片厚度1.5mm。 后交聯(lián)甘油浴溫度：204交聯(lián)時(shí)間：5，10，20 秒推薦加工和應(yīng)用條件推薦加工和應(yīng)用條件Petrothene XL 07407 Copolymer Wire and Cable Compound為過氧化物可交聯(lián)無(wú)鹵阻燃聚乙烯

6、電纜料，可適用于電線護(hù)套和電線電纜穿線管，應(yīng)用于公共場(chǎng)所建筑物、電梯間、民用住宅、車船的電線護(hù)套和電線電纜穿線管。本產(chǎn)品的特點(diǎn)：使用溫度可耐120阻燃燃燒時(shí)無(wú)有毒氣體放出燃燒時(shí)無(wú)煙或煙密度很低加工推薦加工溫度在107113，常規(guī)擠出機(jī)，螺桿長(zhǎng)徑比2025，壓縮比2:1或3:1，口模要短，口徑直徑與產(chǎn)品直徑放大比可達(dá)20%，擠出加工后進(jìn)入高溫鹽浴或硫化通道204210進(jìn)行后固化, 停留時(shí)間1520秒。交聯(lián)后的產(chǎn)品可用于125的場(chǎng)合。過濾網(wǎng)最大40目。使用前不需預(yù)干燥。電子束輻射加工電子加速器生產(chǎn)輻照交聯(lián)電線電纜目前，全世界用于工業(yè)的電子加速器有700800臺(tái)，總功率超過20000kW，其中200

7、多臺(tái)應(yīng)用于電線電纜的輻照交聯(lián)，主要集中在北美、歐洲、日本、俄羅斯、中國(guó)及韓國(guó)等國(guó)家。美國(guó)、日本等國(guó)幾乎所有生產(chǎn)電線的大廠都利用電子加速器生產(chǎn)輻照交聯(lián)特種電線電纜。我國(guó)現(xiàn)有電子加速器近60臺(tái)，用于電線電纜輻照交聯(lián)的近50臺(tái)。目前我國(guó)電線電纜輻射加工已成為輻射加工行業(yè)這個(gè)高技術(shù)產(chǎn)業(yè)的基礎(chǔ)。但我國(guó)輻照交聯(lián)電線電纜產(chǎn)品無(wú)論在規(guī)格、品種和技術(shù)等各方面與先進(jìn)工業(yè)國(guó)家仍有相當(dāng)大的差距。輻照設(shè)備10KV交聯(lián)電纜料LDPE100敏化助交聯(lián)劑1.5抗氧劑1010 0.30.6硬脂酸鈣0.5氧化鋅1.5碳酸鈣 1-4炭黑母粒（含量45%） 26 交聯(lián)度80%輻照量 20Mrad硅烷交聯(lián)電纜料一步法兩部分共聚合硅烷交

8、聯(lián)機(jī)理硅烷交聯(lián)電纜料諾基亞一步法電纜生產(chǎn)線Silane Crosslinked PE PEX or XLPE電纜料電纜料苑會(huì)林Silane Crosslinked PE is called PEX or XLPE 無(wú)鹵阻燃塑料一個(gè)新的發(fā)展是在無(wú)鹵阻燃聚烯烴電纜料中采用納米層狀硅酸鹽，以改善材料的阻燃性和降低無(wú)機(jī)阻燃劑的用量。如在以氫氧化鋁阻燃的乙烯-乙酸乙烯酯電纜料中加入5%以下的納米層狀硅酸鹽，電纜料中氫氧化鋁的含量(質(zhì)量分?jǐn)?shù))可由原來(lái)的65%降至45%，而材料釋熱速率峰值仍保持不變，且加工性、成炭性、耐光性和生煙性均有改善。 XPEPEX Pipes Heat Shrinkable tub

9、es Wire and Cable main processes A one step process, called MonosilA two step process called Sioplas Monosil process (One step process) Sioplas process (Two steps process) Effect of silane structure VTMOS (Vinyl trimethoxysilane) reacts much faster than VTEOS (Vinyltriethoxysilanes). Effect of silan

10、e concentration The maximum concentration of VTMOS recommended is 2wt% concentrations can be used but these can result in lower gel contents which might very well prove to be suitable for some applications. Concentrations higher than 2wt% do not lead to significant higher gel contents. Effect of sil

11、ane concentrationInfluence of the Organic Peroxide on PE Crosslinking The peroxide to be used needs to have decomposition kinetics which are suitable for the temperatures and residence times involved in the procesing of polyethylene. Generally DCP, Dicumyl peroxide or BPDIB; t-Butyl di-iso propyl be

12、nzene are recommended. The peroxide level required will vary with individual characterics such as :Melt flow index the initial polyethylene, density, polymerization process.) Desired melt flow index of the grafted PEProcessing temperature during graftingPresence of some additives or fillers Influenc

13、e of the Catalyst on PE CrosslinkingDBTDL, dibutyltindilaurate is the preferred catalyst for crosslinking. Since the concentration of DBTDL affects significantly processability of the mixture of graft copolymers, it is sometime recommended to use it as low as 0.25wt%This reduction in concentration r

14、educes the rate of crosslinking but does not affect the gel content of fully crosslinked graft copolymer Influence of the Process Conditions on PE Crosslinking Process conditions also have a strong impact on moisture crosslinking and final performance. Two key parameters are water temperature and wa

15、ll thickness of the extruded profile. Water temperature Wall Thickness Wall Thickness壁厚 The Crosslinking reaction is fast but diffusion of moisture into the material is a limiting factor. For this reason, the wall thickness of the extruder parts have a strong influence on the time needed to crosslink it. High Speed LineNo Special Equipment RequiredBy adopting a SIOPLAS process, converters have the ability to use commercially available pre-grafted polyethylene (Silanized PE) that can be premixed with a catalyst masterbatch and colormas