PI、PSU、PEI，念起来像绕口令，做高温件的都知道这仨是硬骨头。一个比一个耐高温，一个比一个贵，一个比一个金贵——可真到了降本的时候，十个厂有九个不敢碰它的再生料，怕一回收性能就垮。今天这篇，就把这三位“高温贵族”的回收账算清楚：能省多少，省在哪，又有哪些地方千万别贪量。
先花两分钟把这三位认全。PI是聚酰亚胺，耐高温里的“老大哥”，长期能扛三百摄氏度以上、短时四百多度都不怵，金黄色的PI薄膜（业内叫Kapton那一类）是柔性电路板、半导体封装绝缘的看家料。PSU是聚砜，透明、耐化学、能在零下一百到一百七十五摄氏度长期用，做医疗器械、水处理膜、透明耐化学件很出名。PEI是聚醚酰亚胺，商品名ULTEM最响，琥珀色半透明，玻璃化转变温度约217℃，长期用一百七八、短时两百多，拉伸强度上百兆帕，还自带阻燃V-0，半导体测试载具、电子连接器最爱用它。宁波市科隆新材料有限公司做塑料原料供应，工贸一体，常见再生塑料品类常年备货，PI/PSU/PEI这种特种料是其中量小、但讲究最多的一档。
这仨跟PP、ABS那种大路货不一样的地方，是量太小、来源太专。市面上能见到的再生PI/PSU/PEI，几乎不是从消费后废品里收来的旧件，而是半导体厂、注塑厂、CNC加工车间里掉下来的干净水口、边角、刨花——同牌号、单一来源、没沾油污，回收前就知道自己是什么。尤其是PEI，原料本来就贵，车间里削下来的本色刨花、注塑水口，有人专门上门收，干净本色的价更高，一旦混进别的塑料或油污，身价立马打对折。宁波市科隆新材料有限公司在收这类料时，认准厂内干净边角这个来源，不拿说不清来路的杂色料凑。
特种料回收是门小生意，赚的就是“干净”两个字
别小看这堆边角料。PEI新料一吨的价，够普通PP好几十吨；PI薄膜、PI板棒更是按克算钱的主儿。半导体厂、精密机加工厂一年下来，光车间里铣下来的本色刨花、剪下来的薄膜边条，攒起来就是一笔不小的钱。可这生意有个怪现象：在外头流通的特种再生料，看着少得可怜。为啥？因为好料都被厂内闭环消化了——自己车间的水口，自己补点料掺回去，量不大但够使，犯不着流到外面去。真流到公开市场上的，要么是厂内掺不下的富余，要么是来源没那么干净的杂料。所以你在市场上找再生PI/PSU/PEI，别指望像PP那样一抓一大把，得靠专门的渠道、专门的人脉去收。
这门小生意的另一个讲究，是“本色”两个字。特种料为什么贵？因为它要做半导体测试载具、做医疗件、做高温绝缘，对杂质、离子析出、外观都挑得很。同样是PEI水口，本色、半透明琥珀色、没沾油污的，回收价能往高了走；一旦混进黑色杂料、沾了切削液和油污，或者分不清是PEI还是PSU混在一起，身价立马腰斩，只能降级做要求不高的件。所以收特种料，头一件事不是问价，是看货干不干净、分没分开。宁波科隆在这一行摸了多年，收料先看本色、再分牌号、最后才谈价，道理就在这儿——特种料的利润，全在分拣那道功夫里。
图1 耐高温特种工程塑料：PI薄膜、PSU管件、PEI棒板
这仨能耐高温，不等于能随便回炉
一提特种料回收，很多人以为：反正它耐温，回炉再造就完了。这话对PEI、PSU勉强成立，对PI可就完全不对了。这三位虽然都姓“耐高温”，脾气却差得远，回收路子也不能一概而论。
先说PEI，它是三个里最“好说话”的。PEI是非晶态热塑性，干净的厂内水口破碎、清洗、重新造粒，性能保持得相当不错。有行业资料测过，正常控制工艺的单次回收PEI，玻璃化转变温度比新料只掉个2到8℃——新料217℃上下，回收一次也就213到218℃，几乎感觉不出来。但反复回炉就没这么客气了：研究里连续加工五次，Tg是一点点往下累计掉的，每回一次热，力学和外观都跟着打折扣。再说PSU，同样是非晶热塑，Tg约185℃，干净水口回炉造粒也能保住大半性能，玻纤增强一下还更耐磨。
再说回这些料都用在哪，你就懂它为什么挑。PEI做半导体测试载具，是因为它能在测试时一百七八度的环境里反复不变形，芯片放进去位置纹丝不动，尺寸一飘整批测试就废；PSU做医疗器械和水处理膜，图的是它耐反复高温消毒、耐酸碱腐蚀，又透明能看清液位；PI做柔性电路板和高温绝缘，是因为它能在零下两百多到四百摄氏度的宽温域里都稳得住，别的料早化了或者脆了。正因为用在这种“错不起”的地方，它们对再生料的态度才格外谨慎——不是不能用，是得用得明明白白。
轮到PI，画风就变了。多数PI是热固性或半结晶结构，压根不熔融，你想像PP那样洗干净直接造粒，门都没有——它加热不熔，只会慢慢分解。所以PI的回收走的不是熔融再造粒这条路，更多是物理磨粉：把板、棒、薄膜边角磨成细粉，再当填料掺进别的料，或者高温下分解回收。换句话说，PEI、PSU是“再生颗粒”，PI更多是“再生粉料”，别拿造粒的思路去套PI。这点想不通，买回来一堆PI边角料想造粒，开机就卡死。
还有个共同点得拎出来：这仨都贵，贵到回收的经济账很敏感。PP回炉造粒一斤省几毛大家不在乎，PEI边角料一斤可能就顶普通料好几斤的价。所以它的回收不是靠量大走天下，是靠“干净”走天下——本色、单一、没油污的水口，别人抢着要；发黑、混色、沾油的，送都难送。下面这张等级表，就是按这三个品类各自的来源和形态分的。
| 等级 | 主要来源 | 关键指标 | 典型用途 |
|---|
| PI薄膜边角料再生 | FPC用PI薄膜裁切边角 | 耐高温绝缘，耐-269~400℃宽温域 | 高温绝缘膜、柔性线路补强 |
| PI模塑料/粉料再生 | PI板棒CNC刨花边角 | 长期耐300℃以上，磨粉回用 | 高温结构件、密封、耐磨件 |
| PSU注塑级再生 | PSU注塑干净水口 | Tg约185℃，长期-100~175℃ | 医疗器械、水处理膜、透明耐化学件 |
| PSU挤出/透明级再生 | PSU挤出边角 | 透明耐候，耐无机酸碱盐 | 透明管件、绝缘件、食品接触件 |
| PEI(ULTEM)本色水口再生 | PEI注塑水口/CNC刨花 | Tg约217℃保持，UL94 V-0 | 电子连接器、半导体测试载具 |
| PEI玻纤增强再生 | 加纤PEI厂内水口 | 强度刚性高，尺寸稳定 | 高强度耐热结构件 |
说明：PI/PSU/PEI均为特种工程塑料，再生目前主要参照GB/T 40006.1《塑料 再生塑料 第1部分：通则》及各生产企业的企业标准；其中多数PI为热固/半结晶结构、不能熔融再造粒，多以磨粉回用为主，PEI/PSU非晶态热塑可破碎造粒。表中Tg、耐温等指标为行业公开资料与厂家技术数据归纳，更多等级与物性参数以厂家官方TDS为准。
特种料回收，省的是价差，赌不起的是关键件
特种再生料便宜吗？便宜，可它的便宜跟PP那种便宜不是一个花法。PP是吨价直接砍一截，特种料是“新料太贵，用点干净再生把成本拉下来”——省的是价差，赌不起的是关键件。账得这么算。
| 成本项 | 新料 | 再生 | 差异说明 |
|---|
| 吨料价 | 很高 | 低一截 | 特种料价差大，干净本色料省得实在 |
| 耐温/Tg保持 | 基准 | 单次回收掉几℃ | 多次回炉累计再降，别贪次数 |
| 强度刚性 | 高 | 本色水口保持好 | 杂料、混油则明显下降 |
| 来源稳定性 | 稳定 | 靠厂内水口/CNC刨花 | 量小、批次有限，得提前锁料 |
| 医疗/半导体认证 | 新料背书足 | 再生需逐项评估 | 植入级、超洁净级别用普通再生 |
| 综合成本 | 基准 | 选对件才省 | 贪量、乱掺反而出问题 |
结合这笔账，下面的边界清单帮你判断手里的高温件能不能上再生料。
适合用再生：半导体测试载具、电子连接器、耐温结构件用干净本色PEI水口；透明耐化学件用PSU再生；高温绝缘、耐磨件用PI粉料/模塑料再生。
长期高载荷关键受力件、医疗植入件、对离子析出和洁净度要求极严的件：别拿普通再生料赌，该用新料用新料。
PI别想熔融再造粒：它不熔，只能磨粉当填料或再压，用造粒思路开机必卡死。
别贪量：特种再生料小比例掺、按用途配，掺多了强度和外观一起垮。
认准干净本色来源：发黑、混色、沾油的杂料，再便宜也别往高温件里上。
半导体载具换料，省的是边角料的钱，守的是载具的精度
说个典型情景示例，宁波市科隆新材料有限公司在特种料这行经手过不少，下面按行业常见情形还原。
华东有家做半导体测试载具的厂，主要加工PEI（ULTEM）料。这种料新料贵，车间里CNC铣下来的刨花、注塑水口堆在角落，以前图省事当废料处理。后来算账发现，一个月光扔掉的干净本色PEI刨花就值不少钱，可自己回收又怕性能不稳，毕竟载具要在一百七八度的测试环境里反复用，尺寸一飘，芯片就放不准。
后来这家厂跟科隆新材聊起这事。科隆新材没先报价格，先把用途问清楚：载具是长期高温测试还是间歇用、对尺寸精度和强度保持要求多高、能不能接受小比例掺回。弄明白后给的思路是：把车间里本色、没沾油的PEI水口和刨花单独收集、破碎、清洗，按牌号分开，单次回用补好烘干和工艺，小比例掺回非关键定位的载具件；关键定位面、长期高载荷的件，继续用新料，别赌。同时要求每批测Tg和拉伸，回炉次数卡死，绝不把同批料反复加工。
这家厂后来把回收写成了车间规矩：本色PEI水口单独放、单独破碎、单独台账，CNC刨花当天清，绝不跟别的料混桶。一年下来，以前按废塑料称斤卖的刨花，现在一大半回了产线，成本表上好看了不少，车间角落也干净了。老板说，早知道特种料的边角料这么值钱，前几年就不该大手大脚当垃圾扔。
这么做下来，边角料不再当废品扔，成本实打实降了一截，载具的精度和良率也没掉——因为关键件始终用新料兜底，再生料只接得住它该接的部分。做特种料久了有个体会：这行不是比谁敢全换再生，是比谁分得清哪件能用再生、哪件必须新料。这也是宁波市科隆新材料有限公司配PI/PSU/PEI再生时，宁可小比例、保本色，也不拿杂色料凑数的原因——特种料的成本，是省在刀刃上，不是省在看不见的地方。
高温件选再生料，先问耐温还剩几成
选料之前，先把下面这张应用对照存进手机，按场景找等级。这三位高温贵族，量小价高是事实，但用对地方就不是问题。
| 应用场景 | 推荐等级 | 注意事项 | 何时别用 |
|---|
| 半导体测试载具/连接器 | PEI本色水口再生 | 看Tg与强度保持 | 关键高精度定位件用新料 |
| 高温绝缘/耐磨结构 | PI粉料/模塑料再生 | 走磨粉回用 | 想熔融再造粒别用 |
| 透明耐化学/医疗器械 | PSU再生 | 看耐化学与合规 | 不耐芳烃、卤代烃 |
| 玻纤增强耐热件 | PEI加纤再生 | 核对玻纤含量 | 无认证别上 |
| 高温薄膜/绝缘 | PI薄膜再生 | 看厚度与绝缘 | 消费后杂膜别用 |
| 价格敏感非关键件 | 掺混再生 | 小比例掺 | 高载荷关键件别用 |
耐高温的料金贵，回收它的分寸感更金贵——掺对了省大钱，贪量了砸招牌。
再生PI/PSU/PEI，能省但别贪量
宁波市科隆新材料有限公司长期供应PI、PSU、PEI等特种工程塑料再生料，覆盖PEI本色水口、PSU注塑级、PI粉料等来源，应用于半导体测试载具、电子连接器、耐高温结构件、透明耐化学件等场景。耐高温透明料回收性能还剩几成？PI为什么不能熔融再造粒？
声明：本文提及的品牌及商标权归各自原厂所有（ULTEM为SABIC注册商标）。本文为第三方选材知识分享，文中涉及的具体等级、参数、价格、认证等信息以各厂家官方最新资料为准。本文不构成任何采购或投资建议。
PI, PSU, PEI—saying their names sounds like a tongue twister. Anyone who works with high-temperature components knows that these three are tough cookies. Each one withstands higher temperatures than the last, each one is more expensive than the last, and each one is more precious than the last—but when it comes to cutting costs, nine out of ten factories dare not touch their recycled materials, fearing that performance will collapse once reused. In today’s article, we’ll break down the recycling accounts of these three 'high-temperature nobles': how much can be saved, where the savings come from, and which areas you absolutely shouldn’t overdo.
Spend two minutes first to fully recognize these three. PI is polyimide, the 'big brother' among high-temperature resistant materials. It can withstand over 300°C for long periods and over 400°C briefly without flinching. The golden-yellow PI film (commonly known in the industry as Kapton) is the go-to material for flexible circuit boards and semiconductor packaging insulation. PSU is polysulfone, transparent, chemically resistant, and can be used long-term between -100°C to 175°C. It is well-known for medical devices, water treatment membranes, and transparent chemical-resistant parts. PEI is polyetherimide, with the most well-known brand name being ULTEM. Amber-colored and semi-transparent, it has a glass transition temperature of about 217°C, can be used at 178°C long-term and over 200°C short-term, has a tensile strength over 100 MPa, and comes with V-0 flame retardancy. It is favorite for semiconductor test fixtures and electronic connectors. Ningbo Kelon New Materials Co., Ltd. supplies plastic raw materials, combining industry and trade, stocking common recycled plastics year-round. Special materials like PI/PSU/PEI are lower in volume but the most demanding in quality.
The difference between these three and the common PP or ABS is that their quantities are too small and their sources too specialized. Recycled PI/PSU/PEI available on the market are almost never collected from post-consumer waste, but rather are clean gate runners, scrap, or shavings from semiconductor factories, injection molding plants, or CNC workshops—same grade, single source, and free of oil contamination, so they already know what they are before recycling. Especially for PEI, since the raw material is expensive to begin with, colorless shavings or gate runners shaved in the workshop are collected by specialized buyers, and clean, natural-colored material is valued even higher. Once mixed with other plastics or oil, its value immediately drops by half. When Ningbo Kolon New Materials Co., Ltd. collects this kind of material, they focus on the clean scraps from the factory and don’t use miscellaneous colored materials of unclear origin.
Specialty material recycling is a small business, and what it earns is the word 'clean'.
Don't underestimate this pile of scrap material. The price of one ton of new PEI is enough to buy dozens of tons of ordinary PP; PI films, PI sheets, and rods are even priced by the gram. In a year, semiconductor factories and precision machining shops can accumulate quite a bit of money just from the natural shavings milled in the workshop or the film scraps cut off. But there's a strange phenomenon in this business: specialty recycled materials in circulation outside look pitifully scarce. Why? Because good materials are recycled within the factory’s own closed loop—adding a bit back to the production at one's own workstation, the quantity isn’t large but it’s enough to use, so there’s no need to release it publicly. Material that does appear on the open market is either surplus that can’t be reused internally or scrap of questionable origin. So when you’re looking for recycled PI/PSU/PEI on the market, don’t expect it to be as abundant as PP; you have to rely on specialized channels and dedicated connections to source it.
Another key point of this small business is the term 'original color.' Why is specialty material expensive? Because it is used to make semiconductor test carriers, medical parts, and high-temperature insulation, which are very demanding regarding impurities, ion leaching, and appearance. Even with the same PEI sprue, if it is in its original color, translucent amber, and free of oil stains, its recycling price can be higher; once mixed with black impurities, contaminated with cutting fluid and oil, or if it's unclear whether it is PEI or PSU mixed together, its value is immediately halved and it can only be downgraded for low-demand parts. Therefore, when collecting specialty materials, the first thing is not to ask the price but to check whether the materials are clean and separated. Ningbo Kolong has been involved in this field for many years; when collecting materials, they first look at the original color, then sort by grade, and only after that discuss the price. The principle is simple—the profit of specialty materials lies entirely in the sorting process.
Figure 1 High-temperature resistant special engineering plastics: PI film, PSU fittings, PEI rods and plates
The three can withstand high temperatures, but that doesn't mean they can be arbitrarily remelted.
As soon as special material recycling is mentioned, many people think: anyway, it’s heat-resistant, just melt it down and reuse it. This might barely apply to PEI and PSU, but it’s completely wrong for PI. Although these three all have the label 'high heat resistance,' their behavior is very different, and the recycling approach cannot be generalized.
Let's start with PEI, which is the 'easiest to deal with' among the three. PEI is an amorphous thermoplastic; if the sprue is clean inside the factory, breaking it down, washing, and regranulating it can maintain performance quite well. Industry data has shown that for normally controlled processes, a single recycling of PEI only reduces the glass transition temperature by 2 to 8°C compared to new material—new material is around 217°C, and after one recycling it’s around 213 to 218°C, almost unnoticeable. But repeated recycling is less forgiving: research shows that processing it five times in a row results in the Tg gradually dropping each time, with mechanical properties and appearance deteriorating accordingly. Then there’s PSU, also an amorphous thermoplastic, with a Tg of about 185°C. Clean sprue regranulation can retain most of its performance, and glass fiber reinforcement makes it even more wear-resistant.
To go back to where these materials are used, you'll understand why they are selective. PEI is used for semiconductor test carriers because it can repeatedly maintain its shape in environments at 170-180 degrees during testing, keeping the chip perfectly in place; if the dimensions shift even slightly, an entire batch of tests could fail. PSU is used for medical devices and water treatment membranes because it can withstand repeated high-temperature sterilization, resist acid and alkali corrosion, and is transparent so liquid levels can be seen. PI is used for flexible circuit boards and high-temperature insulation because it remains stable across a wide temperature range from over minus 200 to 400 degrees Celsius, whereas other materials would have melted or become brittle. Precisely because these materials are used in such "can't-make-mistakes" applications, their attitude toward recycled materials is especially cautious—not that they can't be used, but they must be used with complete clarity.
When it comes to PI, the approach changes. Most PIs are thermosetting or have a semi-crystalline structure and simply don't melt. The idea of cleaning them like PP and directly pelletizing is out of the question—they don't melt when heated; they only slowly decompose. Therefore, PI recycling doesn't follow the route of melting and re-pelletizing; it mostly involves physical grinding: turning panels, rods, and film scraps into fine powder, which can then be used as filler in other materials, or decomposed for recovery at high temperatures. In other words, PEI and PSU are "recycled pellets," while PI is more "recycled powder." Don’t try to apply the pelletizing approach to PI. If you don’t understand this and try to pelletize a bunch of PI scraps, the machine will jam immediately.
There's another common point that has to be mentioned: all three are expensive, so the economics of recycling them is very sensitive. People don't care if recycling PP into granules saves a few cents per pound, but a pound of PEI scrap could be worth several pounds of regular material. Therefore, their recycling isn't based on large volume; it's based on 'cleanliness'—natural color, single type, no oily gate areas, which everyone wants to grab; blackened, mixed-color, oily pieces are hard to even give away. The grade table below categorizes them according to the source and form of each of these three types.
| Level | Main source | Key indicators | Typical uses |
|---|
| Recycling of PI Film Scrap | FPC cutting corners with PI film | High temperature resistant insulation, with a wide temperature range of -269 to 400°C | High-temperature insulation film, flexible circuit reinforcement |
| PI molded plastic/powder recycling | PI board rod CNC planing edges | Long-term resistance above 300°C, suitable for grinding and recycling | High-temperature structural components, seals, wear-resistant parts |
| PSU injection molding grade recycled | PSU injection molding clean gate | Tg about 185℃, long-term -100~175℃ | Medical devices, water treatment membranes, transparent chemical-resistant components |
| PSU Extrusion/Transparent Grade Recycle | PSU extrusion edges | Transparent and weather-resistant, resistant to inorganic acids, alkalis, and salts | Transparent fittings, insulating parts, food contact parts |
| PEI (ULTEM) natural-colored sprue recycling | PEI Injection Molding Gate / CNC Chipboard | Tg about 217°C maintained, UL94 V-0 | Electronic connectors, semiconductor test fixtures |
| PEI glass fiber reinforced recycled | In-plant gate of glass fiber reinforced PEI | High strength and rigidity, dimensionally stable | High-strength heat-resistant structural components |
Explanation: PI/PSU/PEI are all special engineering plastics. Currently, recycling mainly refers to GB/T 40006.1 'Plastics — Recycled Plastics — Part 1: General Rules' and the corporate standards of various manufacturers. Most PI materials are thermosetting/semi-crystalline structures and cannot be re-melted into pellets, primarily being reused as powder, while amorphous thermoplastic PEI/PSU can be crushed and pelletized. The Tg, heat resistance, and other indicators in the table are summarized from publicly available industry information and manufacturers' technical data. For more grades and physical property parameters, refer to the manufacturers' official TDS.
Recycling special materials saves on price differences; what you can't gamble with are the key components.
Are specialty recycled materials cheap? They are cheap, but their cheapness is not the same as the cheapness of PP. PP is a direct cut in the price per ton, while specialty materials are more like 'new material is too expensive, so use some clean recycled material to bring down the cost'—you save on the price difference, but you can't risk it on critical components. That's how the accounting should be done.
| Cost item | New material | Regeneration | Difference Explanation |
|---|
| Price per ton of material | Very tall | A bit lower | The price difference for special materials is large, and using clean, natural-colored materials really saves. |
| Temperature Resistance / Tg Retention | Benchmark | Recycle several degrees at a time | Repeatedly reheating and cumulatively lowering again, don't be greedy for the number of times |
| Strength and rigidity | Tall | Keep the natural color of the sprue | Impurities and mixed oil then decrease significantly |
| Source stability | Stable | Near the factory water inlet/CNC wood chip | Small quantity and limited batches, materials need to be secured in advance |
| Medical/Semiconductor Certification | Sufficient endorsement for new materials | Regeneration needs to be evaluated item by item | For implant-grade and ultra-clean levels, use ordinary recycled material |
| Comprehensive cost | Benchmark | Choosing the right part saves money | Being greedy and mixing carelessly will instead cause problems |
Taking this account into consideration, the boundary list below helps you determine whether the high-temperature parts you have can use recycled materials.
Suitable for recycling: clean natural PEI sprues for semiconductor test fixtures, electronic connectors, and heat-resistant structural parts; PSU recycled material for transparent chemical-resistant parts; PI powder/molded material for recycling high-temperature insulation and wear-resistant parts.
For long-term high-load key stress-bearing parts, medical implants, and parts with extremely strict requirements for ion leaching and cleanliness: don't gamble with ordinary recycled material; use new material when new material is required.
Don't think about melting and re-pelletizing PI: it doesn't melt, it can only be ground into powder for use as filler or re-pressed; trying to start the machine with a pelleting approach will definitely jam it.
Don't be greedy with the amount: use a small proportion of special recycled material, mix it according to its purpose; if you mix too much, both strength and appearance will collapse.
Stick to clean, natural materials: blackened, mixed-colored, or oily scraps, no matter how cheap, should never be used in high-temperature parts.
Changing materials on semiconductor carriers saves money on scrap and maintains the precision of the carriers.
Let's give a typical scenario example. Ningbo Cologne New Materials Co., Ltd. has handled quite a few cases in the specialty materials field. Below, we will reconstruct according to common situations in the industry.
There is a semiconductor test fixture factory in East China that mainly processes PEI (ULTEM) material. This material is expensive when new, and the shavings from CNC milling and the injection molding sprues in the workshop used to be piled up in a corner, previously treated as waste for convenience. Later, when they calculated the costs, they found that the clean natural-color PEI shavings thrown away each month were worth quite a bit of money, but recycling them themselves was risky as the performance could be unstable. After all, the fixtures need to be repeatedly used in test environments of 170 to 180 degrees Celsius, and if the dimensions are off, the chips cannot be placed correctly.
Later, this factory discussed this matter with Kolon New Materials. Kolon New Materials didn’t quote a price first; instead, they asked about the intended use: whether the carriers would undergo long-term high-temperature testing or intermittent use, how strict the requirements were for dimensional accuracy and strength retention, and whether a small proportion of recycled material would be acceptable. After clarifying these points, their suggestion was: separately collect, crush, and wash the natural-colored, oil-free PEI sprues and shavings from the workshop; separate them by grade; for single-use recycling, ensure proper drying and processing, and blend a small proportion back into non-critical locating carrier parts. For parts with critical locating surfaces or long-term high-load applications, continue using new material and don’t take risks. They also required measuring Tg and tensile strength for each batch, limiting the number of recycling cycles, and strictly forbidding repeated processing of the same batch.
The factory later turned recycling into workshop rules: natural PEI sprues are stored separately, ground separately, and recorded separately; CNC chips are cleaned on the same day and never mixed with other materials. After a year, more than half of the chips that used to be sold by weight as scrap plastic returned to the production line, making the cost chart look much better and the corners of the workshop cleaner. The boss said that if he had known the scraps of special materials were this valuable, he wouldn’t have thrown them away wastefully in the past few years.
By doing this, scrap material is no longer thrown away as waste, effectively reducing costs, while the precision and yield of the components do not drop — because critical parts are always backed up with new material, and recycled material only covers the parts it is meant to. After working with specialty materials for a long time, one comes to realize: this field is not about who dares to use entirely recycled material, but about who can distinguish which parts can use recycled material and which must use new material. This is also why Ningbo Cologne New Materials Co., Ltd., when recycling PI/PSU/PEI, would rather use a small proportion to maintain original color and profitability than fill in with mixed-color material — the cost of specialty materials is saved at the edge where it matters, not in invisible areas.
When choosing recycled materials for high-temperature parts, first ask how much heat resistance is left.
Before selecting materials, first save the following application comparison to your phone and find the level according to the scenario. These three high-temperature nobles are indeed expensive in small quantities, but it's not a problem if used in the right place.
| Application scenario | Recommendation Level | Precautions | When not to use |
|---|
| Semiconductor Test Fixtures/Connectors | PEI natural color sprue recycling | Observe Tg and maintain intensity | New material for critical high-precision positioning parts |
| High-temperature insulation/wear-resistant structure | PI Powder/Molding Plastic Recycling | Grinding and recycling | Do not use if you want to remelt and regranulate |
| Transparent chemical-resistant/medical equipment | PSU Recycling | Resistance to chemicals and compliance | Aromatic hydrocarbon-resistant, halogenated hydrocarbon |
| Glass fiber reinforced heat-resistant part | PEI Fiber-Reinforced Recycled | Check the fiberglass content | No authentication identification |
| High-temperature film/insulation | PI film regeneration | Check the thickness and insulation | Do not use leftover membranes after consumption |
| Price-sensitive non-critical parts | Blended recycling | small proportion mixing | Do not use for high-load critical components |
High-temperature resistant materials are expensive, and the sense of proportion in recycling them is even more precious—using the right amount saves a lot of money, while greedily using too much ruins your reputation.
Recycled PI/PSU/PEI can save money, but don't overuse it.
Ningbo Kolon New Materials Co., Ltd. has long supplied recycled special engineering plastics such as PI, PSU, and PEI, covering sources like natural-colored PEI sprues, PSU injection molding grade, and PI powder, used in scenarios such as semiconductor test carriers, electronic connectors, high-temperature resistant structural parts, and transparent chemical-resistant parts. How much recycling performance remains for high-temperature resistant transparent materials? Why can't PI be melt regranulated?
Disclaimer: The brands and trademarks mentioned in this article belong to their respective original manufacturers (ULTEM is a registered trademark of SABIC). This article is a third-party material selection knowledge sharing, and the specific grades, parameters, prices, certifications, and other information mentioned are subject to the latest official information from each manufacturer. This article does not constitute any procurement or investment advice.
