做手术器械的厂都清楚，PSU（聚砜）这东西是透明耐高温件里出了名的硬角色——能反复扛高压蒸汽灭菌，透明、韧、尺寸稳。可偏偏每年量产翻车，翻得最冤的也是它。
河南许昌有家做手术器械配套件的厂，去年一批PSU透明器械托盘，正牌报价压不下来，采购图便宜进了一批来路不明的"副牌"。上机打出来倒是透亮，结果过了三轮134℃高压蒸汽灭菌，托盘边一圈全泛白、一碰就脆裂，两千多套整批退回。
问题不复杂：副牌没选对档。今天把PSU副牌这事讲透——它到底从哪来、和正牌差在哪、哪几家国外大厂的副牌值得碰。
它是什么，池子有多深
PSU，学名聚砜（Polysulfone），琥珀色透明的非晶特种工程塑料，热变形温度一百六七十度起步，能反复蒸煮、耐稀酸稀碱，是医疗透明件、食品接触、水处理膜的常客。说白了，普通透明PC煮几次就发雾变形，PSU扛得住。
全球PSU这池子不大，高度集中在几家国外大厂手里。按产能与市场份额口径（多家行业研究机构交叉核验，2025—2026）：
索尔维（Solvay，旗下特种聚合物业务现属Syensqo）：聚砜家族龙头，代表牌号Udel（PSU）、Radel（PPSU）、Veradel（PESU），聚砜类全球年产能约三万吨级，份额领先；
巴斯夫（BASF，德国）：代表牌号Ultrason S（PSU）、Ultrason E（PESU）、Ultrason P（PPSU），份额约两到三成，供应网络覆盖多国；
住友化学（日本）：代表牌号Sumikaexcel（以聚醚砜PESU为主），千叶厂 neat resin 年产能约六千吨，是聚砜家族第三家主要国外供应商。
国内江门优巨、山东horan等属于大陆厂商，不在本文"前三国外企业"的讨论范围。
副牌不是次品，是同一批料的另一档
先把概念钉死。PSU副牌不是次品料，更不是回收料。
定义很简单：同一厂家、同一牌号，出厂检验时没完全踩中正牌技术指标的那部分。同一批聚合料，化验合格贴正牌标，个别指标小幅浮动就是副牌。
四大来源也固定：装置开停车的头尾料；牌号切换时的过渡料；工艺波动导致熔指、色相、透光、灰分里某一项小幅超标的批次；副线尾料。
关键性质是——它仍是原厂原生聚合粒子，分子结构和正牌一致，只是个别指标小幅浮动。和回料、再生料的边界必须拎清：
| 类型 | 来源 | 品质 | 典型用途 |
|---|
| 正牌 | 原厂达标批次 | 全指标达标、批次稳定 | 高要求认证件、植入级 |
| 副牌 | 原厂未完全达标批次 | 个别指标小幅偏离，基材与正牌一致 | 内件、配色件、一般结构件 |
| 回料/水口料 | 加工边角料再造粒 | 已受过一次热历史 | 低要求制品 |
| 再生料 | 废旧塑料回收造粒 | 性能波动大 | 低端制品、填充 |
一句话：PSU副牌是"原厂原粒"，不是"回炉再造"。
索尔维Udel：透明医疗件的默认选项
索尔维的Udel是PSU里绕不开的招牌。这家比利时公司在聚砜领域技术积累深，医疗级认证齐，Udel的透明级、耐蒸汽级长期是手术器械盒、麻醉面罩、灭菌托盘的默认选择之一。
它的副牌特点很明确：大多出在色相（黄度指数YI）或熔指上小幅浮动，分子骨架没变。做非透明或允许小幅色差的结构内件、过滤膜支撑件、一般食品接触件，这种副牌完全够用；但要做反复灭菌、外观高透的件，就得认准正牌或精选副。
适用场景：水处理膜、液体过滤、一般耐热结构件。
巴斯夫Ultrason S：电子电气的稳当选择
巴斯夫Ultrason S系列是PSU另一支主力，德国路德维希港与韩国丽水都有产线，电子电气和汽车热管理用得多。Ultrason S的副牌，常见浮动项是流动长度和热变形温度，密度、拉伸这类主干性能反而稳。
巴斯夫副牌在渠道里口碑偏稳，批次相对整齐。适合做汽车水室周边、电池隔热件、电子接插件这类对透明要求不高、但耐热耐化学要在线的件。它的包装分大包装和小包装两种，进厂按用途领对应档就行。
适用场景：电子电气、汽车耐热件。
住友Sumikaexcel：膜级小众玩家
住友化学的Sumikaexcel主打聚醚砜（PESU），在聚砜家族里是第三家主要国外供应商，千叶厂2018年扩到年产能六千吨，其自称全球PESU份额约两成。
它的副牌相对小众，流动性和色相浮动常见，膜级、医疗级偏多。对国内采购来说，住友副牌量不大、渠道窄，适合做水处理超滤膜、透析膜这类对纯度要求高但非外观件的应用。别拿它去跟索尔维Udel比透明外观级，定位本就不同。
适用场景：水处理膜、医疗分离膜。
副牌避坑：三个坑要绕开
PSU副牌采购，三个坑最常见。
一、别只看价格。色相YI和熔指是PSU副牌最常飘的两项，做医疗灭菌件必须先留样过蒸汽循环，黄度超标的别上透明件。
二、分清用途。做透明外观件、反复灭菌认证件，宁可贵用正牌或精选副；做内件、配色件、膜支撑件，普通副完全够。
三、批次要可溯。同一副牌不同批次色相可能差一档，下单前确认批次、要求留样，别把两批混着打外观件。
包装上大厂副牌也就大包装、小包装两种，别被"定制规格包装"的说法带偏。
科隆仓库现货｜PSU视频
主推品牌：索尔维/世索科、德国巴斯夫、日本住友化学
主要牌号：Udel、Ultrason S、Sumikaexcel
包装规格：原厂原包，分大包装与小包装两种；小包副牌、箱装副牌、大包料/吨包料分档码放，按批量备货
仓库现货：PSU副牌仓库现货5000吨左右
现货明细：小包副牌备货800-1000吨、箱装副牌备货300-500吨、大包料/吨包料备货3500-3900吨
供应保障：先测后签，进厂先把关键指标测一遍，对上用途再签合同
选型口诀与一个许昌案例
选型口诀记五条：
透明灭菌件，认正牌不贪便宜；
内件、膜支撑，副牌能省一截；
先测黄度和熔指，再谈价；
批次留样，两批别混打外观；
认准Udel、Ultrason、Sumikaexcel三家原厂原粒。
许昌有家做手术器械配套的厂，早年图便宜进过一批来路不明的"PSU副牌"，三轮蒸汽灭菌后脆裂退货，良率掉到六成。后来换了索尔维Udel的精选副牌，先过蒸汽循环留样再上机，退货率从十几个点压到零点几个点，透明托盘一次做净。这就是副牌选对档的价值——把翻车在量产之前拦住。宁波市科隆新材料有限公司做进口大厂副牌多年，这类案子每年处理不少。
PSU副牌别急着拆包上机，黄度、耐蒸汽、熔指三样对上用途，再谈价格。
Surgical instrument manufacturers know that PSUs (polysulfone) are a famously tough part among transparent high-temperature resistant parts—they can withstand repeated high-pressure steam sterilization, are transparent, tough, and have stable dimensions. But every year, mass production fails, and it's the one that suffers the most.
Xuchang, Henan, there's a factory that makes surgical instrument components. Last year, a batch of PSU transparent instrument trays couldn't be sold at a genuine price, so they bought a batch of unknown "sub-brands" for cheap purchases. The machine produced clear results, but after three rounds of 134°C high-pressure steam sterilization, the pallet edges turned completely white and cracked at the slightest touch, and over 2,000 sets were returned in batches.
The problem isn't complicated: the secondary brands weren't chosen in the right range. Today, let's thoroughly explain the issue of PSU secondary brands—where does it come from, how does it differ from the genuine brand, and which foreign major manufacturers' secondary brands are worth touching.
What is it? How deep is the pool?
PSU is Polysulfone, an amber-colored, transparent amorphous special engineering plastic with a heat deformation temperature starting at 160–70 degrees. It can be repeatedly steamed and boiled, resistant to dilute acids and alkalis, and is a regular in medical transparent parts, food contact, and water treatment films. Simply put, ordinary transparent PCs mist and deform after a few boils, but PSUs can withstand it.
Global PSU pools aren't big, but they're heavily concentrated in the hands of a few major foreign manufacturers. By capacity and market share (cross-verification by multiple industry research institutions, 2025–2026):
Solvay (Solvay, its specialty polymer business now belongs to Syensqo): Leader in the polysulfone family, representative grades Udel (PSU), Radel (PPSU), Veradel (PESU), global annual polysulfone capacity about 30,000 tons, leading market share;
BASF (Germany): representative grades Ultrason S (PSU), Ultrason E (PESU), Ultrason P (PPSU), with a market share of about 20-30%, supply network covering multiple countries;
Sumitomo Chemical (Japan): Representative grade Sumikaexcel (mainly polyethersulfone PESU), Chiba plant's neat resin annual capacity is about 6,000 tons, making it the third major foreign supplier in the polysulfone family.
Domestic brands like Jiangmen Youju and Shandong Horan, which are mainland manufacturers and are not included in the discussion of the "top three foreign companies" in this article.
Sub-brand is not defective product, but another tier of materials from the same batch
First, let's lock down the concept. PSU sub-brand is not defective material, nor is it recycled material.
The definition is simple: the same manufacturer and grade, but the part that did not fully meet the technical specifications of the genuine brand during factory inspection. If the same batch of polymer material passes testing and is labeled as genuine, and a slight fluctuation in certain indicators is considered a secondary grade.
The four main sources are also fixed: the starting and stopping materials for the plant; the transition material during grade changes; the batch where process fluctuations cause slight exceedances in certain areas such as melting index, hue, light transmission, or ash content; and secondary line residue.
The key property is that it is still the original factory's original polymer particles, with molecular structure consistent with the genuine brand, with only slight fluctuations in some indicators. The boundary between recycled and recycled materials must be clearly defined:
| Type | Origin | Quality | Typical Use |
|---|
| Genuine Brand | Original Factory Standard Batch | All Indicators Compliant, Batch Stability | High-Requirement Certification Documents, Implantation Grade |
| Subbrand | Original factory batch not fully compliant | Slight deviations in some indicators, base material consistent with genuine brand | Internal parts, color-matched parts, general structural parts |
| Reused/sprue material | Processed edge scraps repelled and pelletized | Already experienced once heat history | Low requirements products |
| Recycled Material | Recycled Plastic Pelletizing | Significant Performance Fluctuations | Low-End Products, Filling |
In a nutshell: PSU's secondary brand is 'original factory pellets', not 'remanufactured from the remolder'.
Solvay Udel: The default option for transparent medical devices
Solvay's Udel is an unavoidable signature among PSUs. This Belgian company has deep technical expertise in the polysulfone field and has complete medical-grade certifications. Udel's transparent and vapor-resistant grades have long been among the default choices for surgical instrument boxes, anesthesia masks, and sterilization trays.
's sub-brand features are very clear: mostly appear in slight fluctuations on hue (yellowness index YI) or melting fingers, with the molecular framework unchanged. For non-transparent or slightly colored component structural components, filter membrane supports, and general food contact parts, this sub-brand is more than sufficient; But for repeatedly sterilized and highly transparent parts, you must choose genuine or selected sub-brands.
Applicable scenarios: water treatment membranes, liquid filtration, general heat-resistant structural components.
BASF Ultrason S: A reliable choice for electronics and electrical components
BASF Ultrason S series is another main PSU manufacturer, with production lines in Ludwigshafen, Germany, and Yeosu, South Korea, widely used in electronics, electrical, and automotive thermal management. Common variants for Ultrason S include flow length and thermal distortion temperature, while core properties like density and tensile strength are more stable.
BASF secondary brands have a stable reputation in the channel, with relatively uniform batches. Suitable for automotive water compartment peripherals, battery insulation parts, electronic connectors, and other parts that do not require high transparency but require good heat and chemical resistance. Their packaging comes in large and small packages; you can get the corresponding grade according to your intended use.
Applicable scenarios: electronics and electrical equipment, automotive heat-resistant parts.
Sumitomo Sumikaexcel: a niche player in the membrane segment
Sumitomo Chemical's Sumikaexcel focuses on polyethersulfone (PESU), making it the third major foreign supplier in the polysulfone family. In 2018, the Chiba plant expanded its annual capacity to 6,000 tons, claiming about 20% of the global PESU market share.
Its sub-brand is relatively niche, with frequent flow and hue fluctuation, and mostly membrane-grade and medical-grade. For domestic procurement, Sumitomo's sub-brand is small in volume and has narrow channels, making it suitable for applications like water treatment ultrafiltration membranes and dialysis membranes, which require high purity but do not require appearance. Don't compare it to Solvay Udel for transparent appearance-grade products; their positioning is fundamentally different.
Applicable scenarios: water treatment membranes, medical separation membranes.
Avoid pitfalls for secondary brands: avoid three pitfalls when sourcing
PSU secondary brands; these are the most common pitfalls.
1. Don't just look at price. Hue YI and fuse index are the two most common issues with PSU secondary brands. For medical sterilization parts, samples must be retained and steamed first; if yellowness exceeds the standard, do not use transparent parts.
2. Distinguish the purpose. For transparent exterior parts or repeatedly sterilized certified parts, it's better to use genuine or selected parts; For inner parts, color-matched parts, and membrane support parts, ordinary parts are more than enough.
3. Batch numbers must be traceable. Different batches of the same brand may have different color grades. Before ordering, confirm the batch and require samples to be retained. Don't mix two batches for external parts.
Packaging: Major sub-brands only offer large and small packages. Don't be misled by the phrase "custom specification packaging."
Cologne warehouse stock | PSU video
Main recommended brands: Solvay/Sesoko, BASF Germany, Sumitomo Chemical (Japan )
Main grades: Udel, Ultrason S, Sumikaexcel
Packaging specifications: original factory packaging, available in large and small packaging; Small parcel sub-brand, boxed sub-brand, large package/ton material stacked in batches, stocked according to batch
warehouse stock: PSU sub-brand warehouse stock is about 5,000 tons
Spot Details: Small package secondary brand stock 800-1000 tons, boxed secondary brand stock 300-500 tons, large package/per-ton material stock 3500-3900 tons
Supply Guarantee: Test first, sign later. Measure the key indicators at the factory first, then sign the contract based on suitability for use
Selection Mnemonic and a Xuchang Case
Remember five points for the selection mnemonic:
For transparent sterilized parts, choose the correct brand and don’t go cheap;
For inner parts and membrane supports, secondary brands can save a bit;
Test yellowness and melt index first, then discuss price;
Keep samples for each batch, don’t mix the appearance of two batches;
Stick to the original pellets from Udel, Ultrason, and Sumikaexcel.
There’s a factory in Xuchang that makes accessories for surgical instruments. In the early years, they bought a batch of unknown-source "PSU secondary brand" to save money. After three rounds of steam sterilization, the parts became brittle and were returned, and the yield dropped to 60%. Later, they switched to Solvay Udel’s selected secondary brand, tested samples in steam cycles before production, and the return rate dropped from over ten percent to less than one percent, with transparent trays all processed successfully in one go. This illustrates the value of choosing the right secondary brand—to prevent failures before mass production. Ningbo Kolon New Materials Co., Ltd. has been producing secondary brands for major import manufacturers for years and deals with quite a few such cases annually.
Don’t rush to unpack and run PSU secondary brands. Make sure yellowness, steam resistance, and melt index match the intended use before discussing price.
