做工程塑料的圈子里，有个不大摆在台面上的鄙视链：做PEEK、做LCP的，觉得自己玩的是高端局；做PPS、做PA的，自认是中坚；轮到SPS，很多人压根没听过，觉得它就是个冷门小料。
但有意思的是，每年汽车热管理和电子封装那批件，翻来覆去找材料，最后点名的恰恰是这个冷门料。凭什么？
因为SPS把三件事捏在了一起：轻质、耐热、耐水解，介电还稳。汽车水室、接插件、电子封装，这些件以前用PPS、用PA6T，现在越来越多转SPS。更绝的是，全球能正经规模化做SPS基料的，基本就一家日本厂。这个冷门料，是个独家生意。
SPS到底是什么
SPS是间规聚苯乙烯，syndiotactic polystyrene。听着跟普通PS是亲戚，其实差远了。
普通PS是无规结构，脆、耐热差，做一次性饭盒的。SPS用茂钛催化剂做出来，分子链上的苯环整齐地排在两侧，成了结晶性塑料。结晶一上来，耐热就上去了，热变形温度能到两三百度，还耐水解、耐化学，介电常数低而稳。
它轻，密度比PPS小；它耐水解，泡在防冻液里不发软；它介电稳，高频信号穿过不发虚。所以汽车水室、发动机周边的结构件、电子接插件、高频封装件，都认它。
但它贵，还难买。因为基料全球几乎一家独供。
全球做SPS的，基本就是出光一家
按产能口径，SPS这个品类没有"前三"好排，因为基料的规模化商业生产，全球几乎被日本出光兴产一家垄断。这是个实打实的寡头格局。
出光兴产（Idemitsu Kosan）。 SPS是出光1985年在实验室里首次合成成功，1997年实现工业化的看家产品，品牌叫XAREC。它在日本千叶有一套装置，后来又在马来西亚建了第二套，2022到2023年第二套商业投产之后，全球SPS树脂产能翻了一倍，合计大约两万多吨一年。出光自己的说法是，从原料苯乙烯单体到SPS聚合再到改性造粒，一条龙通吃。
历史上，出光曾经跟美国陶氏（Dow）在德国合资建过SPS装置，但那个合资早就退出了。现在市面上流通的SPS基料，九成以上挂着XAREC的牌子。
那其他国外厂呢？严格做SPS基料的，确实找不出第二家规模化玩家。你能见到的其他"SPS料"，要么是出光基料拿去做的改性造粒料，要么是对标性能的替代合金。所以这篇不硬凑三家国外企业，按实际梯队写——基料看出光，改性看下游。
这也带来一个现实问题：出光对基料出口有管控，很多地区的客户只能买到它的改性料，买不到纯基料自己配。所以市面上流通的"出光SPS副牌"，要格外留心它是基料副牌还是改性副牌。
副牌通识：SPS副牌飘在哪
副牌的道理通用：同一厂家同一牌号，出厂检验个别指标没踩中正牌下沿，就是副牌。四大来源——开停车头尾料、牌号切换过渡料、正常生产中熔指/耐热/色相小幅飘移的批次、副线尾料。它还是原厂原生粒子，分子链跟正牌同源。
SPS副牌飘的指标，常见在三处：一是玻纤含量小幅偏差（SPS大量做玻纤增强牌号，玻纤含量差一点，刚性就飘）；二是热变形温度下沿低一点；三是色相或熔指小幅飘。
边界还是那条：正牌全达标、批次稳；副牌个别指标小幅飘、基材同源；回料是边角料再造粒；再生料是废旧回收。SPS因为基料垄断，市面上拿回收PS冒充SPS副牌的事不是没有，务必看原厂包装标识。
出光XAREC的副牌，汽车件怎么用
出光XAREC的主力牌号，大量是玻纤增强的SPS，牌号比如S932、S104这一类，玻纤含量从百分之十几到百分之四十几排成谱。它的副牌，主要飘在玻纤含量和耐热温度上。
做汽车水室、做恒温器壳体这些件，对耐水解和耐热要求高，但对玻纤含量差个两三个百分点不敏感。XAREC副牌在这类件上很能打。做高频接插件，对介电稳定性要求极高，这种件用正牌，别拿副牌省那点料钱。
出光改性料的副牌，跟基料副牌分清
出光在日本、美国、欧洲、中国都有改性造粒基地。市面上你见到的XAREC料，很多是改性造粒料。改性料的副牌，飘的是配方级的指标，比如某个阻燃剂含量、某个填充量。
挑这种副牌，先问清是纯基料还是改性料，再问飘的是哪一项。改性副牌的好处是拿来就能注塑，不用自己配；坏处是配方是别人的，换批次要重新试机。
副牌选购避坑：SPS三件事
第一，认准XAREC牌子。SPS基料全球就出光一家，不是这个牌子的"SPS副牌"要打个问号。
第二，分清真基料还是改性料。用途不同，验收方法不同。
第三，包装看大小。SPS副牌大包装小包装都有，小包装试机，大包装量产。
科隆仓库现货｜SPS防晒
主推品牌：日本出光兴产（XAREC）。
主要牌号：S932、S104等玻纤增强系列。
包装规格：大包装、小包装都有，小包装试机打样，大包装、吨包料量产摊薄。
仓库现货：SPS副牌仓库现货通常在3000-6000吨，常年备货不断档。
其中小包副牌备货500-800吨、箱装副牌备货200-400吨、大包料/吨包料备货2500-4800吨，按订单配比灵活出。
供应保障：原厂原包直采，批次留样可追。
选型口诀和一个真实案例
选SPS副牌，先看水解老化、再卡玻纤含量、最后对车厂耐温认证，三项过了再装车。
做SPS副牌选型，记住这五条：一看件对介电稳不稳，二认清XAREC牌子，三分基料还是改性料，四按批量选大小包装，五留批次留样。
说个案例。吉林市有家做汽车热管理结构件的厂，做恒温器壳体和水室部件，一直用出光XAREC玻纤增强正牌，一吨料十几万，一个壳体的材料成本压不下来。换过一批便宜的PPS替代，结果耐水解过不了车厂认证，泡防冻液后尺寸飘了，那批件被退回来。后来我们给它配了XAREC同牌号的副牌，玻纤含量差两三个点、耐热温度在控制范围，耐水解和耐化学跟正牌一致。换上去之后，壳体材料成本降了一截，车厂那道耐水解老化测试一次通过，批次良率稳在九成四。
这就是SPS副牌的用法——把对玻纤含量不敏感的结构件分流出去。宁波市科隆新材料有限公司做进口副牌多年，SPS这类冷门垄断料，类似的配比每年调不少，说白了就是帮你把汽车件的耐水解和成本，在量产之前平衡好。
做汽车结构件、做水室、做接插件的，谁还没被SPS的供应卡过？是正牌基料拿不到只能买改性料？还是图便宜进了冒充的回料？或者副牌回来发现玻纤含量差太多？
资料与数据来源
出光兴产官网XAREC SPS产品页及马来西亚第二套装置商业投产公告（2023-12）
出光兴产官方SPS产品资料PDF（产能数据）
国家先进高分子材料产业创新中心《全球SPS供应格局》（2026-01）
贤集网《金发科技抢夺SPS话语权》（出光市场份额数据）
LM立木信息咨询《全球与中国间规聚苯乙烯行业报告（2026版）》
数据
In the circle of engineering plastics, there is an unofficial hierarchy of disdain: those working with PEEK and LCP think they are playing in the high-end league; those working with PPS and PA consider themselves the backbone; when it comes to SPS, many people haven't even heard of it and think it's just an obscure minor material.
But interestingly, every year for automotive thermal management and electronic packaging, when looking for materials over and over, in the end, the one singled out is precisely this obscure material. Why is that?
Because SPS combines three things: lightweight, heat resistance, and hydrolysis resistance, while also maintaining stable dielectric properties. Components like automotive water chambers, connectors, and electronic packaging used to be made with PPS or PA6T, but now more and more are switching to SPS. What's even more impressive is that globally, basically only one Japanese company can produce SPS base material at a proper scale. This niche material is a monopoly business.
What exactly is SPS?
SPS is syndiotactic polystyrene. It sounds like it's related to regular PS, but it's actually very different.
Ordinary PS has an irregular structure, is brittle, and has poor heat resistance, and is used to make disposable lunch boxes. SPS is made using a metallocene catalyst, and the benzene rings on the molecular chains are neatly arranged on both sides, making it a crystalline plastic. Once it crystallizes, the heat resistance increases, the heat distortion temperature can reach two to three hundred degrees, and it is also resistant to hydrolysis, chemicals, and has a low and stable dielectric constant.
It is light, with a density smaller than PPS; it is hydrolysis-resistant and does not soften when soaked in antifreeze; it has stable dielectric properties, and high-frequency signals pass through without attenuation. Therefore, automotive water tanks, components around the engine, electronic connectors, and high-frequency packaging parts all use it.
But it is expensive and hard to buy, because the base material is almost exclusively supplied by one company worldwide.
Globally, the only company that really does SPS is basically Ushio.
By production capacity standards, SPS in this category does not have a 'top three' ranking, because the mass commercial production of the base material is almost entirely monopolized globally by just one company, Idemitsu Kosan of Japan. This is a truly oligopolistic structure.
Idemitsu Kosan. SPS is Idemitsu's signature product, first successfully synthesized in a laboratory in 1985 and industrialized in 1997, branded as XAREC. There is a facility in Chiba, Japan, and later a second facility was built in Malaysia. After the second commercial production started from 2022 to 2023, the global SPS resin capacity doubled, totaling about more than 20,000 tons per year. According to Idemitsu, they handle the entire process from styrene monomer to SPS polymerization to modification and pelletizing.
Historically, Idemitsu once formed a joint venture with Dow in Germany to build an SPS plant, but that joint venture exited a long time ago. Now, more than 90% of the SPS base materials circulating on the market bear the XAREC brand.
What about other foreign manufacturers? It's indeed hard to find a second large-scale player that strictly produces SPS base materials. The other 'SPS materials' you can see are either modified pellets made from Mitsui base materials or alternative alloys that match the performance. So this article won't force three foreign companies just for the sake of it; it will write according to the actual tiers—base materials from Mitsui, modifications from downstream.
This also brings a practical problem: Idemitsu controls the export of base materials, so customers in many regions can only buy its modified materials and cannot purchase pure base materials to blend themselves. Therefore, special attention should be paid to whether the "Idemitsu SPS sub-brand" circulating on the market is a base material sub-brand or a modified sub-brand.
Side Deck General Knowledge: Where Does the SPS Side Deck Float
The principle of secondary brand is universal: for the same manufacturer and the same grade, if individual indicators in factory inspection miss the lower limit of the standard brand, it is considered a secondary brand. The four main sources are: leftover material from the beginning and end of production runs, transitional material during grade changes, batches with slight variations in melt index/heat resistance/color during normal production, and leftover material from secondary lines. It still consists of the original factory's native particles, with molecular chains originating from the same source as the standard brand.
Indicators for SPS sub-brands to fluctuate are commonly seen in three areas: first, a slight deviation in glass fiber content (SPS produces a large number of glass fiber reinforced grades, and if the glass fiber content is slightly off, the rigidity fluctuates); second, a slightly lower heat deformation temperature; third, slight fluctuations in color tone or melt flow index.
The boundaries are still the same: the main brand fully meets the standards and has stable batches; the secondary brand has a few indicators slightly fluctuating, but the base material comes from the same source; reprocessed material is made from edge scraps; recycled material is from collected waste. Because SPS dominates the base material, it is not uncommon for recycled PS to be passed off as secondary SPS on the market, so be sure to check the original packaging and labels.
How to use Idemitsu XAREC's sub-brand automotive parts
The main grades of Idemitsu XAREC are mostly glass fiber reinforced SPS, with grades such as S932 and S104. The glass fiber content ranges from a little over ten percent to over forty percent, forming a spectrum. Its secondary grades mainly vary in glass fiber content and heat resistance temperature.
Making car water jackets and thermostat housings requires high hydrolysis and heat resistance, but is not sensitive to a two or three percent difference in glass fiber content. XAREC's sub-brand performs very well on these parts. For high-frequency connectors, which require extremely high dielectric stability, use the main brand for these parts—don't try to save a little money with the sub-brand.
The by-brand of Idemitsu modified material, distinguish it from the by-brand of base material
Idemitsu has modified granulation bases in Japan, the United States, Europe, and China. Many of the XAREC materials you see on the market are modified granulated materials. The sub-brands of modified materials often highlight formulation-level specifications, such as the content of a certain flame retardant or the amount of a certain filler.
When choosing this kind of secondary brand, first ask clearly whether it is pure base material or modified material, and then ask what aspect is variable. The advantage of modified secondary brands is that they can be used for injection molding immediately, without having to mix it yourself; the disadvantage is that the formula belongs to someone else, and you need to re-test the machine when changing batches.
Choosing Side Plates to Avoid Pitfalls: Three Things About SPS
First, choose the XAREC brand. There is only one manufacturer of SPS base material in the world; if it's an 'SPS sub-brand' not from this brand, you should be skeptical.
Second, distinguish between genuine base material and modified material. The purposes are different, and the acceptance methods are different.
Third, look at the size of the packaging. SPS sub-brand has both large and small packaging; small packaging is for trial runs, large packaging is for mass production.
Cologne Warehouse In-Stock｜SPS Sunscreen
Main recommended brand: Idemitsu Kosan (XAREC) from Japan.
Main grades: S932, S104, and other glass fiber reinforced series.
Packaging specifications: Both large and small packages are available. Small packages are for trial runs and sampling, while large packages and ton bags are for mass production and cost dilution.
Warehouse stock: SPS sub-brand warehouse stock is usually between 3,000-6,000 tons, with continuous year-round supply.
Among them, the small-pack secondary brand is stocked at 500-800 tons, the boxed secondary brand at 200-400 tons, and the large-bag/ton-bag material at 2500-4800 tons, to be flexibly dispatched according to the order ratio.
Supply assurance: Direct procurement from the original factory with original packaging, batch samples retained for traceability.
Selection mnemonic and a real case
When choosing an SPS sub-brand, first check hydrolysis aging, then fiber glass content, and finally the automaker's temperature resistance certification. Only after passing all three should it be used in vehicles.
When selecting SPS sub-brands, remember these five points: First, check if the parts are stable with the dielectric; second, identify the XAREC brand; third, distinguish between base material and modified material; fourth, choose packaging size and size according to batch; fifth, keep batch samples for reference.
Let me share a case. In Jilin City, there is a factory that makes automotive thermal management structural parts, producing thermostat housings and water chamber components. They have always used the genuine Chuguang XAREC glass fiber reinforced brand, with over a hundred thousand yuan per ton, and the cost of materials per shell cannot be reduced. They tried replacing it with cheap PPS substitutes, but the hydrolysis resistance failed the manufacturer's certification. After soaking in antifreeze, the size floated, and the batch was returned. Later, we paired it with a sub-brand of the same grade as XAREC. The glass fiber content differed by two or three points, the heat resistance was within a controlled range, and the hydrolysis and chemical resistance were consistent with the genuine brand. After switching, the cost of the shell material dropped significantly, and the car factory's hydrolysis aging resistance test passed on the first try, with a batch yield rate stable at 94%.
This is how SPS secondary brands are used—diverting structural parts that aren't sensitive to glass fiber content out of the market. Ningbo Kelong New Materials Co., Ltd. has been doing imported secondary brands for years. For niche monopoly materials like SPS, the ratio is adjusted quite a bit every year. Basically, it's to help you balance the hydrolysis resistance and cost of automotive parts before mass production.
For automotive structural parts, water chambers, and connectors, who hasn't been blocked by SPS suppliers? Is it because they can't get genuine base materials and have to buy modified materials? Or did they buy counterfeit recycled materials for cheapness? Or did they find the glass fiber content difference is huge when they return from the secondary brand?
Data and Data Sources
Idemitsu Kosan Official Website XAREC SPS Product Page and Malaysia Second Plant Commercial Production Announcement (2023-12)
Idemitsu Kosan Official SPS Product Information PDF (Capacity Data)
National Advanced Polymer Materials Industry Innovation Center "Global SPS Supply Landscape" (2026-01)
Xianji.com "Kingfa Technology Competes for SPS Discourse Power" (Idemitsu Market Share Data )
LM Limu Information Consulting "Global and China Inter-Regulated Polystyrene Industry Report (2026 Edition)"
Data
