减震垫用半年就压塌，回弹再也回不来。高回弹TPE，回弹率虚标就是换层皮。
翻车现场：回弹不足，件就“塌”了
高回弹 TPE，用在缓冲垫、密封件、鞋材中底、减震件上——翻车现场几乎都是“塌”：
现场一：缓冲垫压几次就塌，回弹不回来——压缩永久变形大，回弹是空话；现场二：密封件长期受压，
恢复不到原位——密封间隙越来越大，泄漏是迟早；现场三：中底跑几周就变薄——**回弹疲劳，能量回归率掉得快。
**
密封件选回弹料看长期压变：长期受压，回弹不足就漏——回弹密封件的“长期压缩永久变形”是核心数，比初始回弹重要。
初始回弹好只是表象，长期压变才是真相。
压缩永久变形还有个“测试条件”陷阱：压缩比、温度、时长不同，数据完全不同——同样的料，25% 压缩 22h 和 50% 压缩 70h，结果差很远。
要数据的时候，把“测试条件”一起要来，条件不同不能直接比。
回弹跟着温度往下走：温度越低，回弹越差——低温场景的回弹件，要专门看“低温回弹数据”，不是常温数据覆盖一切。
北方冬天用回弹件，数据要按低温工况出。北方回弹件，常温报告别直接当结论。
回弹不足，件就塌了——高回弹 TPE 的选型，压缩永久变形是硬指标。
回弹件在往轻量化走：微发泡、低密度是行业方向——同样回弹，重量轻 20%，产品竞争力强一截。
轻量化和回弹的平衡，是新材料开发的主线。轻和弹要一起平衡。
结构设计直接改回弹体验：形状、厚度、筋位，都影响回弹表现——同样材料，结构设计好，回弹体验能提升一档。
选料和结构设计要一起做，别只盯着材料牌号。
原因拆解：回弹的两个数
回弹不是“手感软”——是两个数的组合：压缩永久变形（变形后恢复能力）和能量回归率（冲击后的回弹效率）。
| 指标 | 看什么 | 合格线参考 |
|---|
| 压缩永久变形 | 长期受压后的恢复 | 25% 以内（视工况） |
| 能量回归率 | 冲击回弹效率 | 越高越好 |
| 回弹率 | 自由回弹高度 | 按件要求 |
技术金句：高回弹 TPE 的选型，先对压缩永久变形，再对能量回归率——两个数，定回弹真假。
压缩永久变形的测试条件要写死：常用 70℃×22h、压缩率 25% 的标准；测出来超过 30% 的料，别拿来做长期受压的密封件。
密封件自身的压缩量按 15%-25% 设计，压超 30% 回弹就回不来。
| 步骤 | 动作 | 输出 |
|---|
| 一 | 定动静工况 | 指标清单 |
| 二 | 定温度 | 难度判断 |
| 三 | 对数据 | 回弹结论 |
排查步骤：三步锁回弹料
- 1. 定工况：静态受压还是动态冲击？——静态看压缩永久变形，动态看能量回归率；
- 2. 定温度：回弹件在什么温度用？——温度高了，回弹掉得快；
- 3. 对数据：要压缩永久变形（含测试条件）、能量回归率数据——测试条件不同，数据不能直接比。
使用频率决定材料等级：缓冲垫天天受压和偶尔受压，要求不同——天天受压的，要“长期压缩永久变形”小；偶尔受压的，
短时回弹够用就行。
使用频率写进工况，等级才定得准。
密度和回弹是一对矛盾：密度高，回弹挺但重；密度低，轻但塌——所以回弹件的密度设计要和材料选择一起做，
别只盯着材料牌号。
密度压下来了，回弹也容易跟着塌。
压塌怎么救：料、配方、体系三处改
料的方向：同体系内调回弹——回弹靠体系弹性，也靠配方里的交联和填料比例。填料加多了，回弹就掉。
硬度高低不等于回弹好坏：同体系下，硬度高回弹不一定好，硬度低回弹不一定差——回弹是“交联结构+配方”的结果，
不是硬度的附属品。
所以选回弹料，硬度只是参考，回弹数据才是依据。
配方的方向：油分和填料的平衡是回弹的核心——油多软但回弹差，填料多硬但回弹也差。专业配方，才敢同时报“软 + 回弹好”。
给回弹件采购一个“三数据”标准：压缩永久变形、能量回归率、疲劳后回弹保持率——三个数据齐了，回弹件选型就赢了一半。
三个数据缺一个，供应商的报价就要打问号。
回弹测试要对仪器口径：能量回归率、回弹率用不同仪器测，结果不能直接比——要数据时，把“测试仪器和标准”一起要来。
口径对齐，供应商之间的数据才能横向比。
体系的方向：高回弹的主力是 TPEE 和 SEBS 基（高弹配方）——TPEE 回弹+耐温好，SEBS 基性价比高；TPV 回弹一般，重回弹场景别硬选。
寿命预期要按压缩次数算：鞋中底按几十万次，密封缓冲件按实际使用频率——选料时把“目标压缩次数”告诉供应商，
材料等级才能定准。
寿命预期，是回弹件选型的隐藏参数。鞋中底几十万次、密封件按年算，差着量级。
科隆客户案例：溶胀变形跟产调，老化一次过
烟台一家改性料应用厂，回弹件耐油性不足，泡油后溶胀变形。科隆配合现场跟产调试到良率稳定，一次性通过 1000h 老化测试。
回弹件的问题，常常是“回弹”和“耐介质”没兼顾——参数对齐，两项一起稳。
泡油会拖回弹：回弹件泡油，回弹会下降——油里的密封缓冲件，要“回弹+耐油”双数据。双要求的件，别只看回弹单指标。
回弹料到货查这四项，回弹率必测
- 1. 查变形数据：压缩永久变形（按实际工况的压缩比、温度、时长）；
- 2. 查回归率：能量回归率数据，按件的使用场景定；
- 3. 查疲劳：反复压缩后的回弹保持率，动态件的关键；
- 4. 批次留样：回弹件对批次敏感，留样对比。
四查里，疲劳数据最容易被省
| 验收项 | 看什么 | 要点 |
|---|
| 变形数据 | 压缩永久变形 | 按工况测 |
| 回归率 | 能量回归率 | 按场景定 |
| 疲劳 | 反复压缩保持率 | 动态关键 |
| 留样 | 批次留样 | 对比 |
静态回弹好，不等于疲劳回弹好。
小结
压缩永久变形 25% 以内，是回弹件的基本盘，过了这条线再谈手感。
高回弹 TPE 的用料没有标准答案，只有最合适的答案——工况定指标、指标定体系、数据定结论，回弹件才弹得回来。
配方透明度决定数据可信度：回弹料的油分、填料比例，直接影响回弹和长期稳定性——要求供应商提供“配方大致构成+回弹数据对照”，比只看价格靠谱。配方透明的供应商，回弹数据才敢信。只报价不报油分比例的，数据多半经不起对。
给回弹件采购一个“试件验证”动作：材料数据齐了，还要做成型试件（实际形状、实际厚度）测回弹——形状和厚度影响回弹表现。试件数据达标，才敢放量。材料级数据和试件级数据，两关都过才保险。
最后补一个“留样复测”：回弹件每批留样，三个月后复测压缩永久变形——回弹是会“漂”的指标，批次稳定性要靠复测盯住。留样复测，是回弹件批次管理的常规动作。
微发泡是中高端路线：微发泡 TPE 密度低、回弹好，但泡孔均匀性难控制，批次波动大。选微发泡料，批次稳定性验收要加严，泡孔均匀性要抽检。泡孔均匀，回弹才均匀，批次才稳。
回弹件的应用面很广：鞋中底、密封圈、缓冲垫、防震垫、瑜伽用品、医疗器械手柄——遍布各个行业。选型先定“动态/静态”，再定“压缩比/频率”，指标就清晰了。
这两天接了个电话，头一句是“你们的尼龙耐多少度”。
The shock-absorbing pad collapses after half a year, and the rebound never comes back. High-rebound TPE with a falsely claimed rebound rate is just putting a new layer of skin on it.
Accident scene: insufficient rebound, the part just 'collapsed'
High-resilience TPE, used in cushioning pads, seals, shoe midsoles, and shock-absorbing components — the failure scene is almost always 'collapsed':
Scene 1: The cushion collapses after being pressed a few times and does not rebound — the permanent compression is large, and rebound is just empty talk; Scene 2: The sealing part has been under pressure for a long time,
Cannot return to the original position—the sealing gap keeps getting larger, leakage is only a matter of time; On-site case three: the midsole thins after a few weeks of running—**rebound fatigue, energy return rate drops quickly.
**
When selecting sealing materials, consider the rebound material for long-term compression set: if subjected to long-term pressure and rebound is insufficient, it will leak—the 'long-term compression set' of a rebound sealing element is the core figure, more important than the initial rebound.
Good initial rebound is just a facade; long-term compression changes reveal the truth.
There is also a 'test condition' trap with compression set: different compression ratios, temperatures, and durations yield completely different data—using the same material, 25% compression for 22 hours and 50% compression for 70 hours result in vastly different outcomes.
When requesting data, include the 'test conditions' as well; you can't directly compare them if the conditions are different.
Rebound decreases with temperature: the lower the temperature, the worse the rebound — for rebound components in low-temperature scenarios, you need to specifically look at 'low-temperature rebound data', not assume that room-temperature data covers everything.
In the north, rebound parts are used in winter, and the data should be based on low-temperature conditions. For northern rebound parts, do not directly take the normal temperature report as a conclusion.
Insufficient rebound, and the part collapses — when selecting high-rebound TPE, compressive permanent deformation is a hard requirement.
Rebound parts are moving towards lightweighting: micro-foaming and low density are the industry trends—offering the same rebound, but 20% lighter, making the products significantly more competitive.
The balance between lightness and resilience is the main focus of new material development. Lightness and elasticity need to be balanced together.
Structural design directly affects rebound experience: shape, thickness, and rib placement all influence rebound performance—using the same material, a well-designed structure can improve the rebound experience by one level.
Material selection and structural design should be done together; don't just focus on the material grade.
Cause Analysis: The Two Numbers of Rebound
Rebound is not 'soft feeling'—it is a combination of two numbers: compression set (ability to recover after deformation) and energy return rate (efficiency of rebound after impact).
| Indicator | What are you looking at? | Passing line reference |
|---|
| Compression set | Recovery after long-term pressure | Within 25% (depending on operating conditions) |
| Energy Regression Rate | Impact rebound efficiency | The higher, the better |
| Resilience | Free rebound height | According to the requirements |
Technical Tip: When selecting high-rebound TPE, first consider the compressive permanent deformation, then the energy return rate—these two numbers determine the authenticity of the rebound.
The test conditions for compression set should be fixed: commonly use the standard of 70℃ × 22h with a 25% compression rate; materials that measure over 30% should not be used for long-term compressed sealing parts.
The compression of the seal itself is designed to be 15%-25%; if compressed beyond 30%, it will not rebound.
| Step | Action | Output |
|---|
| One | Static and dynamic operating conditions | Indicator List |
| Two | Set temperature | Difficulty Assessment |
| Three | About data | Rebound Conclusion |
Troubleshooting steps: three-step lock rebound material
- 1. Determine the working condition: static compression or dynamic impact? — For static, look at permanent compression deformation; for dynamic, look at energy recovery rate;
- 2. Set temperature: At what temperature is the rebound piece used? — If the temperature is too high, it will rebound quickly;
- 3. Regarding the data: Compressive permanent deformation (including test conditions) and energy recovery rate data — data under different test conditions cannot be directly compared.
Frequency of use determines material grade: cushioning pads experience daily pressure or occasional pressure, with different requirements—those under daily pressure need a small "long-term compression permanent deformation"; those under occasional pressure,
A short-term rebound is enough.
Only by writing the usage frequency into the working conditions can the grade be determined accurately.
Density and resilience are a pair of contradictions: high density means firm resilience but heavy; low density means light but collapses—so the density design of resilient components must be done together with the choice of materials.
Don't just focus on the material grade.
The density has gone down, and the rebound easily collapses as well.
How to fix collapse: three areas to change—materials, formula, system
Direction of the material: Resilience within the same system—resilience depends on the elasticity of the system, as well as the crosslinking and filler ratio in the formulation. If too much filler is added, the resilience decreases.
Hardness does not equate to rebound quality: within the same system, high hardness does not necessarily mean good rebound, and low hardness does not necessarily mean poor rebound—rebound is the result of the 'crosslinking structure and formulation'.
Not an accessory of hardness.
So choose rebound material; hardness is just a reference, rebound data is the basis.
Formula direction: The balance of oil and fillers is the key to resilience—too much oil makes it soft but poorly resilient, too many fillers make it hard but also poorly resilient. Only professional formulations dare to claim "soft and resilient."
Provide the rebound parts procurement with a 'three-data' standard: permanent compression deformation, energy recovery rate, and rebound retention rate after fatigue—once these three data points are all in place, selecting the rebound parts is already half won.
If one of the three pieces of data is missing, the supplier's quotation becomes questionable.
For rebound tests, the instrument caliber must be considered: energy restitution rate and rebound rate are measured with different instruments, so the results cannot be directly compared — when requesting data, make sure to obtain both the 'testing instrument and standards'.
Only with aligned calibers can data be compared horizontally between suppliers.
System direction: The main materials with high resilience are TPEE and SEBS-based (high-elasticity formulations) — TPEE has good resilience and temperature resistance, SEBS-based offers high cost-performance; TPV has average resilience, and should not be chosen for applications requiring high rebound.
The expected lifespan should be calculated based on the number of compressions: for shoe midsoles, count in hundreds of thousands of times; for sealed cushioning components, calculate according to actual usage frequency — when selecting materials, inform the supplier of the 'target number of compressions'.
The material grade is the only way to determine accuracy.
Life expectancy is a hidden parameter in the selection of elastic components. The midsole of shoes undergoes hundreds of thousands of cycles, while seals are measured in years, differing by orders of magnitude.
Cologne Customer Case: Swelling Deformation and Production Adjustment, Aging Passed in One Go
A modified material application factory in Yantai had rebound components with insufficient oil resistance, swelling and deforming after oil immersion. Kolon cooperated on-site for production adjustment and debugging until the yield stabilized, passing the 1000-hour aging test in one go.
The problem with the rebound component often lies in failing to take both 'rebound' and 'medium resistance' into account—align the parameters, and both can be stable together.
Oil immersion can reduce rebound: When the rebound part is soaked in oil, the rebound will decrease—sealed cushioning parts in oil need both 'rebound' and 'oil resistance' data. For parts with dual requirements, don't just look at the single rebound indicator.
Check these four items when rebound material arrives, the rebound rate must be measured
- 1. Check deformation data: compression permanent deformation (based on actual compression ratio, temperature, duration);
- 2. Check return rate: energy return rate data, depending on the usage scenario of the part;
- 3. Check fatigue: rebound retention rate after repeated compression, key to dynamic parts;
- 4. Batch sampling: rebound parts are sensitive to batches, compare retained samples.
Four Investigations, fatigue data is the easiest to be saved
| acceptance item | what to look at | key points |
|---|
| deformation data | compressed permanent deformation | measured by operating conditions |
| return rate | energy return rate | Scenario-based |
| Fatigue | Repeated compression retention rate | Dynamic key |
| Sample retention | Batch sample retention | Compared to |
Static rebound is better, but that doesn't mean fatigue rebound is better.
Summary
Compression and permanent deformation within 25% is the foundation for rebound parts; after crossing this line, we can talk about tactile feel.
There is no standard answer for high-resilience TPE materials; only the most appropriate answer—determining operating conditions, indicators, systems, data—will rebound parts bounce back.
Formulation transparency determines data reliability: the oil content and packing ratio of rebound material directly affect rebound and long-term stability—require suppliers to provide "rough formula composition with rebound data comparison" to see if price alone is reliable. Suppliers with transparent formulas can trust rebound data. If prices only quote without oil content ratio, the data is often unreliable.
Give rebound parts a "specimen verification" action: once the material data is complete, you also need to make formed specimens (actual shape and actual thickness) to measure rebound—shape and thickness affect rebound performance. Only when specimen data meets standards can you scale up volume. Both material-level and specimen-level data must pass to be safe.
One last "sample retention retesting": re-retaining samples for each batch of rebound parts, then retesting after three months for permanent compression deformation—rebound is a "floating" indicator, and batch stability depends on retesting. Retaining samples for retesting is a routine step in batch management of rebound parts.
Micro-foaming is the mid-to-high-end route: micro-foamed TPE has low density and good rebound, but cell uniformity is hard to control, causing large batch fluctuations. When selecting micro-foamed materials, batch stability acceptance must be stricter, and the uniformity of the foam holes should be randomly checked. Uniform foam holes ensure uniform rebound and stable batches.
Rebound parts have a wide range of applications: shoe midsoles, sealing rings, cushioning pads, shockproof pads, yoga products, medical device handles—these are found across various industries. When selecting a model, first set "dynamic/static," then "compression ratio/frequency," and the indicators become clear.
received a phone call these past couple of days, and the first question was, "How much does your nylon withstand?"
